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Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), has a long association with maize (Zea mays mays L., Poaceae) and is among the crop's most significant pests worldwide. We contrasted the preference for and performance of FAW on three maize cultivars: the Mexican landrace Tuxpeño, the USA inbred B73 and B73‐lox10; B73‐lox10 is deficient in production of jasmonic acid (JA), green leaf volatiles (GLVs) and herbivore‐induced plant volatiles (HIPVs). Female oviposition and neonate colonization preferences were assessed in triple‐choice tests in greenhouse settings. Performance was assessed on the bases of larval, pupal and adult weights, larval and pupal development times, and adult longevity. We expected females to preferentially oviposit on plants on which their offspring performed best, and neonates to randomly colonize plants because they disperse aerially, presumably oriented solely by wind currents. Females preferred to oviposit on Tuxpeño plants, followed by B73‐lox10 and B73 plants, whereas their offspring performed best on B73‐lox10 and poorest on Tuxpeño. In contrast, neonates preferentially colonized plants on which they performed best, B73‐lox10, though initially and transiently they colonized plants on which they performed poorly, B73 and Tuxpeño. Altogether, our results showed that FAW females preferred to oviposit on maize plants on which their offspring's performance was poorest (Tuxpeño), and neonates preferentially colonized plants on which their own performance was best (B73‐lox10), though they initially colonized plants that were detrimental to their performance (Tuxpeño, B73). These results suggested that the ovipositional choices of FAW mothers are uncoupled from their offspring's performance, but newborn offspring rectified their mother's sub‐optimal host plant choice by colonizing plants that enhanced their own performance. Notably, these results also suggested that aerially dispersing (ballooning) FAW larvae do not colonize plants randomly, and that plant volatiles (GLVs, HIPVs) and JA may be relevant to host plant selection by ballooning larvae. [ABSTRACT FROM AUTHOR]

The article "Matching the Dispersal of Baby Clownfish to Oceanographic Currents" explores how ocean currents influence the dispersal of yellowtail clownfish larvae in the central Philippines. By genetically matching offspring to parents, researchers found that while ocean currents play a role in dispersal patterns, other factors such as swimming and navigation also contribute to how far the larvae disperse. The study provides insights into how dispersal variation impacts population persistence and local adaptation in marine species. [Extracted from the article]

ABSTRACT The soldier crab, Mictyris guinotae, is a dominant intertidal crustacean associated with sand flats in the vicinity of the Urauchi River estuary on Iriomote Island, Japan. We compared various aspects of its reproductive biology at two sites (the river mouth and upper reach) on exposed bare sand flats 300 m and 3000 m upstream from the mouth. Bimonthly sampling was conducted between November 2010 and April 2011. The abundance of female crabs was higher at the mouth of the river. Female individuals had significantly larger body sizes (approximately 1.5 times larger carapace length) in the upper reaches. Despite the low presence of ovigerous females in the upper reach site, their larger body size led to the release of a substantial number of larvae per individual, although fewer larvae were produced per day than by females at the river mouth. The breeding period, as inferred from the occurrence of ovigerous females, persisted from December to March. At the upper reach site, the duration was slightly shorter, with an earlier peak. Variations in larval release timing may compensate for fluctuations in recruitment success. [ABSTRACT FROM AUTHOR]

Many marine species have a pelagic larval phase that undergo dispersal among habitats. Studies on marine larval dispersal have revealed a large variation in the spatial scale of dispersal and self‐recruitment. However, few studies have investigated the influence of types of coastline (e.g., bay vs. open coast) on marine larval dispersal. Bays or lagoons generally enhance the retention of larvae, while larvae are more likely to be flushed by strong currents in open coasts. To examine associations between larval dispersal, coastline type, and hydrodynamics, we compared fin‐scale dispersal patterns, self‐recruitment, and local retention (LR) of two anemonefishes (Amphiprion frenatus and Amphiprion perideraion) between a semi‐enclosed bay and an open coast in the Philippines combining genetic parentage analysis and biophysical dispersal modeling. Contrary to our expectations, parentage analysis revealed lower estimates of self‐recruitment in the semi‐closed bay (0%) than in the open coast (14–15%). The result was consistent with dispersal simulations predicting lower LR and self‐recruitment in the semi‐closed bay (0.4% and 19%) compared to the open coast (2.9% and 38%). Dispersal modeling also showed that cross‐shore currents toward offshore were much stronger around the semi‐closed bay and were negatively correlated with LR and self‐recruitment. These results suggest that stronger cross‐shore currents around the semi‐closed bay transport anemonefish larvae to the offshore and mainly contributed to the lower self‐recruitment. Our results highlight importance of hydrodynamics on larval dispersal and difficulty in predicting self‐recruitment from coastline type alone. [ABSTRACT FROM AUTHOR]

Nematodes are common in most terrestrial environments, where populations are often known to undergo cycles of boom and bust. Useful in such scenarios, nematodes present developmental programs of diapause, giving rise to stress-resistant larvae and enabling dispersal in search of new resources. Best studied in Caenorhabditis elegans , stress resistant dauer larvae emerge under adverse conditions, primarily starvation, and migrate to new niches where they can resume development and reproduce. Caenorhabditis elegans is a bacterivore but has been shown to harbor a persistent and characteristic gut microbiome. While much is known about the gut microbiome of reproducing C. elegans , what dauers harbor is yet unknown. This is of interest, as dauers are those that would enable transmission of microbes between nematode generations and geographical sites, maintaining continuity of host-microbe interactions. Using culture-dependent as well as sequencing-based approaches, we examined the gut microbiomes of dauers emerging following population growth on ten different natural-like microbially diverse environments as well as on two defined communities of known gut commensals and found that dauers were largely devoid of gut bacteria. These results suggest that host gut-microbiome interactions in C. elegans are not continuous across successive generations and may reduce the likelihood of long-term worm-microbe coevolution. [ABSTRACT FROM AUTHOR]

Simple Summary: The life cycle of marine benthic invertebrates includes a planktonic larval stage and a benthic adult stage, with larval settlement being the critical transition from a planktonic to a benthic lifestyle. Since adult mobility is limited or completely lost in the benthic environment, larval settlement directly affects population distribution, growth, and reproduction. Although larval settlement induced by natural chemical cues is widespread among marine invertebrates, the molecular mechanisms underlying this process remain unclear. Mytilopsis sallei, a typical marine fouling mussel, releases three purine compounds—adenosine, inosine, and hypoxanthine—that synergistically induce larval settlement. In this study, transcriptomic sequencing was employed to identify differentially expressed genes and signaling pathways associated with purine-compound-induced larval settlement. This research not only provides new insights into the molecular mechanisms of larval settlement in marine benthic invertebrates, but also offers a scientific basis and theoretical foundation for the ecological control of marine fouling organisms. The settlement of marine benthic invertebrate larvae is a crucial stage in their life cycle, directly influencing their population distribution, growth, and reproduction. It is generally believed that multiple chemical inducers in the environment synergistically affect larval settlement, though the underlying molecular mechanisms remain unclear. Our previous study has established that three purine compounds (adenosine, inosine, and hypoxanthine) released by adults of the mussel Mytilopsis sallei synergistically induced larval settlement. In this study, we performed transcriptomic sequencing analysis on larvae exposed to individual purine compounds and those exposed to a combination of three purine compounds. A total of 21,850 differentially expressed genes (DEGs) were identified. KEGG enrichment analysis of these DEGs revealed that the AMPK signaling pathway, FoxO signaling pathway, extracellular matrix (ECM)-receptor interaction, focal adhesion, and the thyroid hormone signaling pathway play key roles in the settlement of M. sallei larvae. Moreover, in larvae exposed to the combined action of three purines, the expression of relevant signaling pathways and metabolic processes was more significant. This research provides important information for understanding the molecular mechanisms underlying the induction of larval settlement in M. sallei by purine compounds in natural environments. [ABSTRACT FROM AUTHOR]

Simple Summary: The introduction of species into a new location is mediated by different factors, including the favorable conditions that the invasive species encounters in the host community. Among the non-native marine species well known for their potential as invasives, the azooxanthellate corals Tubastraea coccinea and Tubastraea tagusensis, introduced in the Caribbean Sea, the Gulf of Mexico and in the Brazilian Southwest Atlantic, stand out for their successful competition for space, multiple reproductive modes and high larval dispersal and recruitment. However, little is known about the feeding and trophic relationships of species of the genus Tubastraea, a gap that we sought to fill in the present study. Here, we show that invaded communities have a lower degree of trophic diversity, with species characterized by similar trophic ecologies. We also show that the invasive coral Tubastraea spp. occupies a trophic niche, similar to that of native species that are suspension feeders. Our results suggest that Tubastraea spp. is also a successful invasive species due to its superior competition for food. When a species is introduced in a new location, it is common for it to establish itself when it finds favorable conditions in the receptor community with regard to interspecific interactions with native species. The azooxanthellate corals Tubastraea coccinea and Tubastraea tagusensis are invasive species introduced in the Caribbean Sea, the Gulf of Mexico, and the Brazilian Southwest Atlantic. They are successful competitors for space, have multiple reproductive modes, and have high larval dispersion and recruitment, but studies on food and trophic relationships of the genus Tubastraea are still scarce. In the present study, we used isotopic values of δ13C and δ15N to investigate trophic relationships in rocky shore communities invaded by T. tagusensis and T. coccinea corals under different oceanographic and anthropogenic contexts. Using metrics derived from the isotopic values, we show that invaded communities have a lower degree of trophic diversity, with species characterized by similar trophic ecologies while abiotic factors seem to contribute to the biotic resistance of communities exposed to invasion events. Tubastraea spp. occupy a niche space similar to that occupied by the native community of suspension feeders, sharing resources already consumed by the receptor community, which makes invading corals successful competitors for food. [ABSTRACT FROM AUTHOR]

The recovery of isolated reef systems is a complex process that is usually associated with the supply of coral larvae from distant reefs (or large‐scale connectivity). However, a frequently neglected process is the potential for supply within the reef itself (or local connectivity). In this study, we quantify and characterize the role of local connectivity over 21 yr of simulated annual coral spawning on an isolated coral reef atoll using outputs from a high‐resolution biophysical model (< 150 m horizontal resolution) along with network analysis. We find that approximatively half of the coral reef larvae dispersal remains local (within 100 s m to 10 s km of release location), while the remaining half contributes to long‐distance dispersal (> 100 s km) and is exported away from the system. Local dispersal plays a pivotal role in creating a highly‐connected network across the reef, enhancing exchanges of larvae within the same reef patches (local retention), across reef zones (e.g., lagoon, reef flat), and across the larger reef system. Finally, we show that this highly‐connected network exhibits a certain level of robustness, even when exposed to environmental stressors such as thermal‐induced mortality. Our findings highlight the previously overlooked role of local scale dispersal in driving recovery of isolated reef systems and emphasize the importance of targeted local management actions, indicating that efforts directed at enhancing and preserving local connectivity can have a substantial impact on the overall health and resilience of isolated reef ecosystems. [ABSTRACT FROM AUTHOR]

Understanding genetic diversity and population connectivity in marine organisms is essential for fisheries management. In the present study, we examined the population genetics of the European squid, Loligo vulgaris, along the western Iberian Peninsula at two genetic resolutions using the mitochondrial cytochrome oxidase subunit I gene (COI) and genomic markers obtained via double digest restriction-site associated DNA sequencing (ddRADseq). The results obtained revealed 79 haplotypes out of 160 COI sequences, while the SNP data set included 86,431 loci after filtering for 38 individuals with 86,319 neutral data. Mitochondrial COI analyses revealed high haplotype (0.961) and nucleotide (0.010) diversities, and the haplotype network reveals complex sub-structure in Turkish waters within a panmictic population. Both Tajima's D and Fu's Fs tests suggest that the population of L. vulgaris analysed is evolving neutrally. Pairwise Fst for neutral SNPs were low (0 < Fst<0.002) and not significant showing high homogeneity among populations, while pairwise comparations for candidate adaptive SNPs (112 loci) showed Fst values ranging from 0.026 to 0.234. While neutral SNPs showed admixture, the candidate adaptive SNPs showed a moderate significant structure with a latitudinal discrimination. Overall, both genetic approaches showed homogeneity and strong genetic flux identifying a unique population along the Western Iberian Peninsula. [ABSTRACT FROM AUTHOR]

Reproduction, embryological development, and settlement of corals are critical for survival of coral reefs through larval propagation. Yet, for many species of corals, a basic understanding of the early life‐history stages is lacking. In this study, we report our observations for ex situ reproduction in the massive reef‐building coral Porites cf. P. lobata across 2 years. Spawning occurred in April and May, on the first day after the full moon with at least 2 h of darkness between sunset and moonrise, on a rising tide. Only a small proportion of corals observed had mature gametes or spawned (14–35%). Eggs were 185–311 μm in diameter, spherical, homogenous, and provisioned with 95–155 algal cells (family Symbiodiniaceae). Males spawned before females, and ex situ fertilization rates were high for the first 2 h after egg release. Larvae were elliptical, ~300 μm long, and symbiotic. Just 2 days after fertilization, many larvae swam near the bottom of culture dishes and were competent to settle. Settlers began calcification 2 days after metamorphosis, and tentacles were developed 10 days after attachment. Our observations contrast with previous studies by suggesting an abbreviated pelagic larval period in Porites cf. P. lobata, which could lead to the isolation of some populations. The high thermal tolerance and broad geographic range of Porites cf. P. lobata suggest that this species could locally adapt to a wide range of environmental conditions, especially if larvae are locally retained. The results of this study can inform future work on reproduction, larval biology, dispersal, and recruitment in Porites cf. P. lobata, which could have an ecological advantage over less resilient coral species under future climate change. [ABSTRACT FROM AUTHOR]

Studies investigating gene flow in sessile or sedentary marine species typically draw conclusions about larval dispersal by investigating genetic structure of adults. Here, we generated microsatellite data from adults, recruits, settlers and planktonic larvae of the brown mussel, Perna perna, from the southeast coast of South Africa, and identified a consistent mismatch in genetic structure between the adults and all earlier life stages. While adults could be assigned to two major geographical groups (western and eastern), most of the early‐stage mussels were strongly affiliated with the eastern group. This suggests that few of the early‐stage individuals present in the western portion of the sampling range will eventually establish themselves in the adult population, highlighting the importance of post‐recruitment processes as drivers of population structure. Our findings caution against the exclusive use of genetic data generated from adults to assess population connectivity facilitated by the dispersal of planktonic propagules. [ABSTRACT FROM AUTHOR]

The black soldier fly (BSF), Hermetia illucens, has the ability to efficiently bioremediate organic waste into usable bio‐compounds. Understanding the impact of domestication and mass rearing on fitness and production traits is therefore important for sustainable production. This study aimed to assess patterns of genomic diversity and its association to phenotypic development across early generations of mass rearing under two selection strategies: selection for greater larval mass (SEL lines) and no direct artificial selection (NS lines). Genome‐wide single nucleotide polymorphism (SNP) data were generated using 2bRAD sequencing, while phenotypic traits relating to production and population fitness were measured. Declining patterns of genomic diversity were observed across three generations of captive breeding, with the lowest diversity recorded for the F3 generation of both selection lines, most likely due to founder effects. The SEL cohort displayed statistically significantly greater larval weight com the NS lines with pronounced genetic and phenotypic directional changes across generations. Furthermore, lower genetic and phenotypic diversity, particularly for fitness traits, were evident for SEL lines, illustrating the trade‐off between selecting for mass and the resulting decline in population fitness. SNP‐based heritability was significant for growth, but was low or non‐significant for fitness traits. Genotype–phenotype correlations were observed for traits, but individual locus effect sizes where small and very few of these loci demonstrated a signature for selection. Pronounced genetic drift, due to small effective population sizes, is likely overshadowing the impacts of selection on genomic diversity and consequently phenotypic development. The results hold particular relevance for genetic management and selective breeding for BSF in future. [ABSTRACT FROM AUTHOR]

Fleas (Siphonaptera) are holometabolous insects with larval and adult stages that exhibit vastly different ecologies from each other. Adult fleas are parasitic and feed exclusively on the blood of a vertebrate host, whereas flea larvae do not live on hosts and consume dried faecal blood from adult fleas. Because flea larvae rely on adult flea faeces for food, excrement and eggs must fall in the same location; thus, larval density is likely high in these restricted habitats. However, the influence of larval density on the subsequent adult stage has not been examined. In the present study, we utilized egg density to investigate density‐dependent effects on larval development and adult body size in the cat flea (Ctenocephalides felis Bouché) (Siphonaptera: Pulicidae). Specifically, eggs were collected to create three different larval densities (n = 50, 100 and 150 per 56.7 cm2), and hatched larvae from all groups were fed an excess amount of adult faecal pellets. Larval development was measured by recording the proportion of eggs that developed to the pupal stage and the proportion of eggs that reached adulthood (eclosion). The body size of eclosed adults was quantified for both sexes using head length and length of the total body. We found that the number of eggs had no effect on the proportion of larvae that pupated or the proportion of larvae that eclosed; however, higher egg densities resulted in larger body sizes for both sexes. Overall, these data yield significant insight into how the ecology of larval fleas impacts the biology of the resultant adults. [ABSTRACT FROM AUTHOR]

Lobster phyllosoma larvae collected during surveys over the continental shelf of eastern South Africa (southwestern Indian Ocean) were analysed to determine the role of the KwaZulu-Natal (KZN) Bight as a pelagic nursery area. Surface waters in the shallow bight and further offshore, between the 20- and 1,000-m depth contours, were sampled with plankton nets in 2018 to 2023. Phyllosomas were absent from 87.9% of 257 tows, with high variability in the remaining tows indicating a patchy distribution with abundance hotspots. Phyllosomas of four scyllarid and three palinurid species were found among 311 captured specimens. The scyllarid Acantharctus ornatus (Holthuis, 1960) was the most abundant, constituting 94.9% of the phyllosomas caught, with all nine larval stages (I–IX) present. Phylogenetic analysis using the COI and 16S rDNA gene markers confirmed that previously undescribed early larval stages in samples belonged to A. ornatus. Most A. ornatus phyllosomas were caught at shallow-bight stations, with catch rates declining steeply to the north and south of the bight and when bottom depth exceeded 100 m. Season and sampling station (nested within cross-shelf transect) were significant variables in explaining phyllosoma abundance. We provide evidence that the KZN Bight serves as a pelagic nursery area for A. ornatus phyllosoma larvae at all developmental stages, but not for other lobster species with known adult populations in the region. [ABSTRACT FROM AUTHOR]

Although the brachyuran crab Carcinus maenas (Linnaeus, 1758) is a globally invasive species, early-life history information for its larvae, such as hatch timing, stage duration, dispersal, and behavior, is limited, particularly in newly invaded locations. This is, in part, due to the need for region-specific guides on larval taxonomy that incorporate C. maenas. We addressed this issue for Washington state marine waters by developing a dichotomous key for the zoeae of C. maenas and a matrix that compares the morphological characters of C. maenas zoeae to those of brachyuran crab families reported from the state. To assess whether morphological characters of C. maenas from this region reflect taxonomic descriptions from the species' native range, we reared zoeae from females collected in Washington state. We found that zoeae from each crab family reported from Washington state have at least two characters that distinguish them from C. maenas zoeae: the presence of lateral carapace spines in most of these families, and for three families lacking lateral carapace spines (Epialtidae, Grapsidae, Pinnotheridae) antennae that are nearly equal to the length of the rostral spine, the presence of posterolateral extensions on any of the somites, or a laterally expanded last somite, respectively. Rearing of larvae showed that the rostral spines of the Washington zoeae I of C. maenas were ~ 0.06 mm longer than reported in the literature. We also found that late-stage zoeae may retain more furcal spines than previously reported. The region-specific taxonomic tools we developed allow easier and quicker identification of C. maenas zoeae in Washington. These descriptions should facilitate early detection in newly invaded bays, a more rapid understanding of C. maenas larval timing and behavior, and better evaluation of larval dispersal that can be used in risk-assessment tools. [ABSTRACT FROM AUTHOR]

An oceanographic cruise from the southern Adriatic to the northern Ionian Sea in May 2013 allowed us to describe the spatial abundance and distribution of decapod crustacean larval assemblages with a multidisciplinary approach. Seventeen locations on the Apulian and Albanian shelves and offshore waters, including the Strait of Otranto, were sampled by a BIONESS electronic multinet. A swarm of zoeae (11 Brachyura taxa, mostly at first instar, with Xantho granulicarpus at 87%) was recorded in the neuston of the Italian side. Decapod larvae were concentrated in the first 20–30 m surface layer, strongly linked to the thermocline and generally above the Deep Chlorophyll Maximum (DCM), suggesting that they are carried by surface water circulation. The migratory behavior of decapod larvae in coastal stations is quite regular at between 20 and 60 m depths and independent of the time of day. In offshore stations, migration is compatible with the day–night cycle, where a minimum Weighted Mean Depth (WMD) value is evident at about 20 m at night. The availability of four satellite-tracked surface drifters in the same area and during the period of larvae presence presented a possibility to explore the link between the geographic dispersal of larvae and their surface circulation in successive days. Only one drifter crossed the south Adriatic, passing from the Italian to the Balkan neritic area, taking about 40 days. The actual genetic homogeneity of many Brachyura coastal species populations on opposite sides of the Adriatic Sea suggests the existence of a genetic connection that does not rely exclusively on larvae circulation and appears to be fueled by additional strategies of biological communication. [ABSTRACT FROM AUTHOR]

The conservation of insects, particularly endangered species such as the Apollo butterfly, is a pressing global concern. Understanding the habitat requirements and factors influencing species occupancy is crucial for designing effective conservation strategies. We focused on investigating the habitat characteristics expected to affect the occupancy of the nationally endangered Apollo butterfly in Southwest Finland. We conducted field surveys and GIS analysis to assess the impact of larval host plant and adult nectar resources, habitat encroachment, elevation, connectivity, and spatial variation on Apollo larval occupancy in rocky outcrop habitats. We found that rocky outcrops with abundant host plants and those less isolated from nectar patches play a significant role in supporting Apollo reproduction, whereas encroachment, specifically increased tree volume, negatively affected occupancy. We additionally observed spatial variation in occupancy across different blocks within the study area. Our findings emphasise the importance of resource availability for Apollo butterflies and highlight the dynamic nature of their habitat requirements. Maintaining a network of intact rocky outcrops with suitable resources is essential for the long-term persistence of the Apollo butterfly population in the region. Implications for insect conservation: Our research underscores the critical need to protect and restore habitats for the Apollo butterfly, particularly by addressing threats such as habitat encroachment and construction projects that pose risks to their breeding sites. [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHW) pose an increasing threat and have a critical impact on meroplanktonic organisms, because their larvae are highly sensitive to environmental stress and key for species' dispersion and population connectivity. This study assesses the effects of MHW on two key moulting cycle periods within first zoea of the valuable crab, Metacarcinus edwardsii. First, the changes in swimming behaviour during zoea I were recorded and associated to moult cycle substages. Then, larvae were exposed during the zoea I to (1) control temperature of 12 °C, (2) Early MHW, occurring in intermoult, (3) Late MHW, occurring in premoult and (4) 14 °C, representing MHW during whole development. Additionally, optimum temperature was estimated from thermal performance curves through swimming behaviour of one-day zoea I. The timing of the MHW within the moulting cycle significantly affects larval fitness. Early MHW led to improved survival rates (72%) and reduced developmental times (9.8 days) compared to those exposed to Later MHW (63% and 10.3 days, respectively). As optimum temperature was higher than 12 °C, MHW events maybe favouring larval performance. These results highlight the importance of interaction between the moult cycle and environmental variables as a factor of sublethal effects on population dynamics. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to compare genetic gain and rate of inbreeding for different mass selection breeding programs with the aim of increasing larval body weight (LBW) in black soldier flies. The breeding programs differed in: (1) sampling of individuals for phenotyping (either random over the whole population or a fixed number per full sib family), (2) selection of adult flies for breeding (based on an adult individual's phenotype for LBW or random from larvae preselected based on LBW), and (3) mating strategy (mating in a group with unequal male contributions or controlled between two females and one male). In addition, the numbers of phenotyped and preselected larvae were varied. The sex of an individual was unknown during preselection and females had higher LBW, resulting in more females being preselected. Results: Selecting adult flies based on their phenotype for LBW increased genetic gain by 0.06 genetic standard deviation units compared to randomly selecting from the preselected larvae. Fixing the number of phenotyped larvae per family increased the rate of inbreeding by 0.15 to 0.20% per generation. Controlled mating compared to group mating decreased the rate of inbreeding by 0.02 to 0.03% per generation. Phenotyping more than 4000 larvae resulted in a lack of preselected males due to the sexual dimorphism. Preselecting both too few and too many larvae could negatively impact genetic gain, depending on the breeding program. Conclusions: A mass selection breeding programs in which the adult fly is selected based on their larval phenotype, breeding animals mate in a group and sampling larvae for phenotyping at random over the whole population is recommended for black soldier flies, considering the positive effect on rates of genetic gain and inbreeding. The number of phenotyped and preselected larvae should be calculated based on the expected female weight deviation to ensure sufficient male and female candidates are selected. [ABSTRACT FROM AUTHOR]

The study of larval dispersal and connectivity between deep-sea populations is essential for the effective conservation and management of deep-sea environments and the design and implementation of Marine Protected Areas. Dense sponge aggregations, known as "sponge grounds", are a key component of marine benthic ecosystems, by increasing the structural complexity of the sea floor and providing structure and habitat for many other species. These aggregations are characteristic of the Azores deep-sea environment. These sessile organisms rely primarily on larval dispersal for their reproduction. Connectivity between specific Pheronema carpenteri sponge aggregations in the Azores was studied using a 3-D biophysical dispersal model. Different biological trait scenarios were analyzed, considering spawning seasonality and pelagic larval duration. Model results indicate that regional circulation patterns drive larval dispersion, shaping population connectivity of P. carpenteri sponge aggregations in the Azores, particularly among aggregations in the Central Group of Azorean islands. Some areas present high retention rates, receiving larvae from several sponge aggregations while also being important larval source aggregations. In contrast, aggregations from the Eastern Group may be isolated from the others. Larval dispersal and connectivity patterns were analyzed concerning the current configuration of Marine Protected Areas (MPAs) in the Azores. The results underscored the importance of maintaining protection efforts in existing MPAs and identified stepping-stone locations and specific sites where additional measures could enhance species connectivity in the Azores. [ABSTRACT FROM AUTHOR]

Fishing activities negatively impact fish populations, potentially causing a decline in fish stocks. Nevertheless, ensuring diversity and connectivity among populations can mitigate these adverse effects. To evaluate the connectivity of river mouths in the western part of Southern Java waters, we sequenced forty Stiphodon semoni individuals from five populations using mitochondrial cytochrome oxidase subunit 1 as molecular markers. The study revealed that S. semoni populations showed high diversity (0.821), with the population in Cimaja displaying the lowest diversity (0.464). Furthermore, the result of the analysis of molecular variance was a Fst value of 0.0630 with a p-value of 0.22. These results, along with the result of the haplotype network, indicated no significant genetic differences among these populations. This implies that the river mouths in the western part of Southern Java waters are interconnected. The distribution of mismatches showed a single peak, indicating that the populations have undergone demographic expansion. This information could be valuable for the conservation and management of S. semoni in the western part of the Southern Java waters. [ABSTRACT FROM AUTHOR]

Human‐transformed residuals, especially those derived from human waste (dumps), farmland, and livestock are involved in the emergence of antibiotic‐resistant bacteria (ARB) in the environment. Wildlife can act as vectors of ARB dispersal through different environments, but also as sentinels to detect the early spread and determine ARB sources. The development of integrated monitoring programmes focused on wildlife would help to anticipate the risks of ARB to humans and livestock.We used the yellow‐legged gull (Larus michahellis) as a model species to investigate and monitor the spatial patterns of ARB dispersal across an extensive farmland region located in northeastern Spain (Lleida). By integrating GPS tracking data and ARB clinical testing for 26 individuals within a network analysis framework, we modelled the risk of spatial pathogen spread through faeces during the bacteria‐transmission latency period (16 days after sample collection). Additionally, we created a connectivity network to determine the main sources of ARB in the area, focusing on three main habitats of special risk for infection: dumps, livestock facilities, and irrigation ponds.Seven individuals were infected by Escherichia coli, with one also co‐infected with Listeria monocytogenes and Salmonella spp. Potential pathogen dispersal distances ranged from 1.13 km to 23.13 km from the breeding colony. Our network analyses revealed 54 main nodes (i.e. high‐risk habitats recurrently visited by tracked gulls) and 1182 links among them. Our findings revealed a high degree of connectivity between the breeding area, located in a shallow lake, and nearby dumps, highlighting them as significant contributors to ARB dispersal.Synthesis and applications: The integration of GPS data, pathogen testing and network analyses can shed further light on pathogen dynamics by creating spatial risk maps and identifying ARB sources. In combination with complementary molecular epidemiology techniques within a One Health framework, our approach can emerge as an important tool for monitoring ARB dynamics within highly human‐transformed ecosystems. This may empower managers for the development of targeted ARB monitoring programmes and effective mitigation strategies, ultimately improving both animal and public health. [ABSTRACT FROM AUTHOR]

Communication plays a fundamental role in the evolution of any form of cooperative behaviour, such as parental care. However, it can be challenging to understand the specific role of certain signals and how they might have evolved into complex communication systems. To investigate what effect a lack of acoustic communication can have on brood care and offspring performance, we silenced parents of biparentally caring burying beetles with a noninvasive method and studied the effect on clutch and offspring performance. Moreover, by analysing three species with varying degrees of offspring dependency on parental care, we aimed to investigate how differing acoustic communication is related to the level of their dependency and if those two align in some way. We used Nicrophorus pustulatus , a nondependent species, Nicrophorus orbicollis , a highly dependent species and Nicrophorus vespilloides , an intermediately dependent species. We found strong effects of silencing parents on offspring performance in all three species. The lack of stridulations impacted offspring weight across all three species. However, our results point towards a difference between species in which development stage communication had the most substantial impact. Looking at larval weight at dispersal, the effects seem to be in line with the larval dependency in the way we would have expected, with N. orbicollis being the most strongly affected, N. vespilloides being also affected and N. pustulatus not being affected. However, looking more closely, we found various differences at other time points and also that larval survival was strongly affected in N. pustulatus. Few studies have looked at the exact function of acoustic signals during brood care with most of them focusing on what type of different signals are emitted rather than what effect they have. Our study is one of the first to start disentangling the interplay of communication and offspring performance. • Silencing parents has a strong effect on offspring performance in burying beetles. • Different species of Nicrophorus differ in communication during brood care. • The larvae of silenced parents are at a disadvantage. • More dependent species do not, per se, rely more on communication. [ABSTRACT FROM AUTHOR]

Understanding how ocean currents influence larval dispersal and measuring its magnitude is critical for conservation and sustainable exploitation, especially in the Tropical Eastern Pacific (TEP), where the larval transport of rocky reef fish remains untested. For this reason, a lagrangian simulation model was implemented to estimate larval transport pathways in Northwestern Mexico and TEP. Particle trajectories were simulated with data from the Hybrid Ocean Coordinate Model, focusing on three simulation scenarios: (1) using the occurrence records of Lutjanus peru and L. argentiventris as release sites; (2) considering a continuous distribution along the study area, and (3) taking the reproduction seasonality into account in both species. It was found that the continuous distribution scenario largely explained the genetic structure previously found in both species (genetic brakes between central and southern Mexico and Central America), confirming that the ocean currents play a significant role as predictors of genetic differentiation and gene flow in Northwestern Mexico and the TEP. Due to the oceanography of the area, the southern localities supply larvae from the northern localities; therefore, disturbances in any southern localities could affect the surrounding areas and have impacts that spread beyond their political boundaries. [ABSTRACT FROM AUTHOR]

Advection of pelagic fish larvae through ocean currents is a source of dispersal that is known to structure marine populations by directly impacting population success and persistence. To be able to understand fish population dynamics and manage existing fisheries it is therefore of importance to assess the extent of exchange between populations and determine the factors that drive it, which is still a challenge in fisheries research today. In this study, the output of a highresolution basin-scale circulation model is used to calculate the dispersal probability from spawning areas and the remaining Black Sea for a range of commercially important fish such as anchovy, sprat, turbot, red mullet, and bluefish under different environmental conditions. The common trait of many commercially important species in the Black Sea is that they have pelagic larval stages of different time scales which are simulated by tracking virtual drifters in the simulated surface circulation of the Black Sea. Simulation results show that the dynamic current structure of the Black Sea causes low local retention of larvae. During spring and summer lower offshore transport and higher local retention is observed than in fall and winter, which is directly related to the Rim Current strength. The lowest offshore transport is observed on the northern northwestern shelf, the main spawning area for pelagic fish with still 24-32% of larvae transported offshore. Simulations show that pelagic fish species such as anchovy and sprat adopted different reproductive strategies through their species-specific traits. For the summer spawning species anchovy, timing, and location of spawning together with its short pelagic larval stage is shown to enhance retention on the northwestern shelf. Sprat with its long pelagic larval stage and winter spawning is more adapted to high offshore transport, making it unlikely that sprat is recruited to the same area as where it is spawned. This modeling framework provides a basis for investigating recruitment variability of pelagic fish species in the Black Sea specifically considering the impact of climate variability and provides a useful guide to the potential connectivity of marine populations or the spread of invasive pests in the Black Sea. [ABSTRACT FROM AUTHOR]

Ocean acidification, caused by increasing atmospheric carbon dioxide and coastal physical, biological, and chemical processes, is an ongoing threat to carbonate-utilizing organisms living in productive coastal shelves. Bivalves exposed to acidification have shown reduced growth, reproduction, and metabolic processes, with larval stages exhibiting the greatest susceptibility. Here, we compile results from published studies on larval bivalve growth responses to acidification to estimate a relationship between larval growth and seawater aragonite saturation state. We then apply this relationship to a larval dispersal individual-based model for Atlantic sea scallops (Placopecten magellanicus), an economically vital species in the Mid-Atlantic Bight that is historically under-studied in acidification research. To date, there have been no published studies on sea scallop larval response to ocean acidification. Model simulations allowed the identification of potential impacts of acidification on scallop success in the region. Results show that larval sea scallops that are sensitive to ocean acidification had a 17% lower settlement success rate and over 50% reduction in larval passage between major Mid Atlantic Bight fisheries habitats than those that are not sensitive to acidification. Additionally, temperature and ocean acidification interact as drivers of larval success, with aragonite saturation states > 3.0 compensating for temperature-induced mortality (> 19 ˚C) in some cases. This balance between drivers influences larval settlement success across spatial and interannual scales in the Mid Atlantic Bight. [ABSTRACT FROM AUTHOR]

Graphical Abstract Research Highlight • The genetic diversity of Stiphodon semoni is high. • All populations have high haplotype diversity except for Cimaja. • No genetic structure is observed within the populations of semoni. • The population of semoni has undergone demographic expansion. • Cibareno River has the potential to be a protected area. Abstract Fishing activities negatively impact fish populations, potentially causing a decline in fish stocks. Nevertheless, ensuring diversity and connectivity among populations can mitigate these adverse effects. To evaluate the connectivity of river mouths in the western part of Southern Java waters, we sequenced forty Stiphodon semoni individuals from five populations using mitochondrial cytochrome oxidase subunit 1 as molecular markers. The study revealed that S. semoni populations showed high diversity (0.821), with the population in Cimaja displaying the lowest diversity (0.464). Furthermore, the result of the analysis of molecular variance was a Fst value of 0.0630 with a p-value of 0.22. These results along with the result of the haplotype network indicated no significant genetic differences among these populations. This implies that the river mouths in the western part of Southern Java waters are interconnected. The distribution of mismatches showed a single peak, indicating that the populations have undergone demographic expansion. This information could be valuable for the conservation and management of S. semoni in the western part of the Southern Java waters.

The European and Japanese eel populations have declined significantly in recent decades. To effectively manage and conserve them, gaining a better understanding of their migratory life cycles is important. Previous research on the spawning ecology and larval dispersal of European and Japanese eels has led to many significant discoveries and advancements for their migratory life cycles. However, different scholars hold varying views on their migratory life cycles, especially concerning the European eel, therefore this article aims to provide a comprehensive review of research from multiple disciplines concerning the spawning ecology and larval dispersal of European and Japanese eels and to propose migratory life cycles of these two species. The migratory life cycle of the European eel is as follows: European silver eels undertake a year‐long spawning migration from September to January to reach the Sargasso Sea for spawning before the next spawning season, typically between December and May. After hatching, European eel leptocephali are transported by the Gulf Stream, Frontal Countercurrents, North Atlantic Current, and Azores Current and return to Europe and North Africa for growth. Recruitment of European glass eels mainly occurs between October and June of the following year, and the recruiting season is more concentrated in countries closer to the spawning area and more dispersed in countries farther away. The consistent recruitment pattern and the growth rate of leptocephali suggest a larval transport period, also called larval duration, of around 1 year. Understanding the migratory life cycle of European eels can facilitate the evaluation or development of their conservation measures. [ABSTRACT FROM AUTHOR]

It was once believed that only microbes and viruses inhabited the subseafloor crust beneath hydrothermal vents. Yet, on the seafloor, animals like the giant tubeworm Riftia pachyptila thrive. Their larvae are thought to disperse in the water column, despite never being observed there. We hypothesized that these larvae travel through the subseafloor via vent fluids. In our exploration, lifting lobate lava shelves revealed adult tubeworms and other vent animals in subseafloor cavities. The discovery of vent endemic animals below the visible seafloor shows that the seafloor and subseafloor faunal communities are connected. The presence of adult tubeworms suggests larval dispersal through the recharge zone of the hydrothermal circulation system. Given that many of these animals are host to dense bacterial communities that oxidize reduced chemicals and fix carbon, the extension of animal habitats into the subseafloor has implications for local and regional geochemical flux measurements. These findings underscore the need for protecting vents, as the extent of these habitats has yet to be fully ascertained. Microbes and viruses inhabit the subseafloor crust beneath hydrothermal vents. Here the authors show that vent endemic animals such as giant tubeworms also live in vent subseafloor cavities, implicating subseafloor dispersal of vent larvae and the need to protect seafloor and subseafloor vent habitats. [ABSTRACT FROM AUTHOR]

Aim: In order to provide a more comprehensive, community‐level understanding of marine gene flow and connectivity, we wished to first identify geographic regions of common spatial genetic divergence across multiple species along a southern temperate coastline, and then to determine which biological and ecological factors best explain the diversity in genetic patterns among species. Location: New Zealand (NZ) marine coastline. Taxon: Twenty‐one species of benthic invertebrate. Materials and Methods: A novel approach was used that involved: (1) use of genetic divergences (FST) from previously published studies to quantitatively describe patterns of population structure within each species as a fitted spline curve, (2) quantitatively clustering species by their similarity in geographic pattern using a dendrogram of curve similarities, and (3) then testing whether nine known life‐history and ecological traits are associated with the species sharing similar genetic patterns, using distance‐based regression. Results: Comparisons among species revealed not one, but four major common geographic patterns, within unexpected groups of species. The common locations of genetic divergence are similar to those previously identified, but differ substantially in their relative importance, compared to prior expectations. Two variables, Spawning Time and Taxon, explained significant proportions (26% and 16%) of the variation in the multivariate data. Main Conclusions: The genogeographic clustering of population genetic divergences provided considerable insight into the concordance of marine spatial structure across species, and some potential biological drivers of those patterns. The four common patterns of population structure identified revealed that different species responded to the same environmental drivers in very different and unexpected ways. Although larval dispersal is an important factor uniting groups of species, the timing of dispersal may be more important than pelagic larval duration in NZ. These results should contribute greatly to the integration of population genetics into both community ecology and conservation management. [ABSTRACT FROM AUTHOR]

Approximately 75% of the world's and California's shores are rocky. Rocky shores are of biological interest owing to their diverse and productive species assemblages, where waves and currents play a critical role in larval dispersal and recruitment. Surface variability for nearshore (5⪅depth⪅60m) $(5\lessapprox \mathrm{d}\mathrm{e}\mathrm{p}\mathrm{t}\mathrm{h}\lessapprox 60\hspace*{.5em}\mathrm{m})$ rocky bottoms at intermediate wave scale 1/750

Fish stocks composed of several populations are considered to have more stable productivity than stocks containing only one or few populations. This stability is attributed to complementary or independent dynamics among the populations within the stock—the so-called portfolio effect. Declines of populations within stocks that have delayed recovery potentially increase risk to productivity and local extinctions. Portfolio effects may be relevant in the Baltic Sea, where autumn-spawning herring was the dominant herring ecotype until the early/mid-20th century. The current fishery assessment and management in the area assumes that the abundance of autumn spawning herring has been negligible since the 1970s; the share of spring spawning herring has become dominant and is considered to be the only ecotype. Data from a multi-annual ichthyoplankton survey in the southern Baltic Sea (Bornholm Basin) during autumn 2002–2019 show that abundance and spatial distribution of the smallest larval stages have increased significantly. This pattern could be due to an increase in autumn spawners in the area. Genetic studies confirm that these larval herring are offspring from true autumn spawners. Preserving intraspecific diversity is critical for a species' future abilities to adapt to and survive in changing environmental conditions. Thus, our results not only provide new insights to the temporal dynamics of herring ecotypes and challenge the current understanding of central Baltic herring stock processes in general, but are also important in the context of monitoring, assessment, and spatial management of herring in the Baltic Sea. [ABSTRACT FROM AUTHOR]

Patterns of population connectivity shape ecological and evolutionary phenomena from population persistence to local adaptation and can inform conservation strategy. Connectivity patterns emerge from the interaction of individual behavior with a complex and heterogeneous environment. Despite ample observation that dispersal patterns vary through time, the extent to which variation in the physical environment can explain emergent connectivity variation is not clear. Empirical studies of its contribution promise to illuminate a potential source of variability that shapes the dynamics of natural populations. We leveraged simultaneous direct dispersal observations and oceanographic transport simulations of the clownfish Amphiprion clarkii in the Camotes Sea, Philippines, to assess the contribution of oceanographic variability to emergent variation in connectivity. We found that time‐varying oceanographic simulations on both annual and monsoonal timescales partly explained the observed dispersal patterns, suggesting that temporal variation in oceanographic transport shapes connectivity variation on these timescales. However, interannual variation in observed mean dispersal distance was nearly 10 times the expected variation from biophysical simulations, revealing that additional biotic and abiotic factors contribute to interannual connectivity variation. Simulated dispersal kernels also predicted a smaller scale of dispersal than the observations, supporting the hypothesis that undocumented abiotic factors and behaviors such as swimming and navigation enhance the probability of successful dispersal away from, as opposed to retention near, natal sites. Our findings highlight the potential for coincident observations and biophysical simulations to test dispersal hypotheses and the influence of temporal variability on metapopulation persistence, local adaptation, and other population processes. [ABSTRACT FROM AUTHOR]

Spiny lobster species are ecologically important and highly prized as seafood globally. Populations of spiny lobsters have been impacted by overfishing, the harvesting of juveniles for seeding aquaculture, the spread of virulent disease, and declines in recruitment and natural habitat. Many spiny lobster populations cover vast geographic ranges, maintained via ocean-going larval dispersal, which makes effective management challenging. Determining the genetic structure and phylogeographic boundaries are important in fisheries and aquaculture for defining appropriate units for management or breeding. Nevertheless, the common patterns of biogeographic distribution and connectivity of spiny lobster populations are generally not well understood. This review summarizes recent genetic advances in our understanding of these patterns and presents several meta-analyses to help discern the common processes driving them. Due to the probable link between biogeographic patterns among species and phylogeographic patterns within species, the spatial patterns of recent genetic stock divergence were investigated with the assistance of a new comprehensive and time-calibrated phylogeny for palinurids. Meta-analyses of biogeographic and phylogeographic patterns were used to identify common patterns of genetic stock divergence. A model is proposed that synthesizes the current understanding of the common processes of divergence of palinurid genetic lineages, emphasizing the importance of allopatry, ecological adaptation, and changing patterns of connectivity over time. Overall, the results highlight the importance of major biogeographic boundaries in structuring spiny lobster stocks over a broad scale, while oceanographic features and stochasticity dominate at smaller scales. These insights will assist the management of spiny lobster fisheries and aquaculture development, by better identifying and understanding the genetic units expected to be most appropriate for management and breeding, even in those species that have not yet received intensive genetic study. [ABSTRACT FROM AUTHOR]

Tetraploids play a crucial role in the large-scale production of all-triploid Pacific oyster, Crassostrea gigas by mating with diploids. For nursery farms, research related to larval tolerance to the environment appears to be extremely important. For this goal, fertilization, embryonic development, growth, and settlement from fertilization stage to metamorphosis stage of the diploid, triploid, and tetraploid larvae of C. gigas "Haida No. 2" strain were studied under controlled conditions of temperature (20, 24, 28, and 32 ℃) and salinity (18, 21, 24, 27, and 30 psu). The results showed that increasing temperature and lowering salinity reduced survival time of sperm while increasing temperature and raising salinity accelerated the germinal vesicle breakdown (GVBD) ratio of stripped eggs in diploids and tetraploids for the first time. The appropriate condition for hatching of four crosses (DD, DT, TD, and TT, males were listed first, D for diploid, T for tetraploid) were listed as follows: 20–28 ℃/27–30 psu for DD, 24 ℃/27–30 psu for DT, 24–28 ℃/27–30 psu for TD, and 24 ℃/27–30 psu for TT. Diploids and triploids had similar performance but were all better than tetraploids under different temperature and salinity. The settlement rate increased with rising temperature while salinity and ploidy had little influence on settlement. The information obtained in this study can contribute to increasing the yield of triploid and tetraploid "Haida No. 2" of C. gigas. [ABSTRACT FROM AUTHOR]

Longitudinal dispersal of migratory fish species can be interrupted by factors that fragment rivers, such as dams and reservoirs with incompatible habitats, and indirect alterations to variables, such as water temperature or turbidity. The endangered pallid sturgeon (Scaphirhynchus albus) population in the Upper Missouri River Basin in North Dakota and Montana is an example of such fragmentation and alteration due to the construction of dams. We applied a high-resolution, 2+-dimensional modelling framework composed of hydrodynamic and Lagrangian particle tracking components to simulate pallid sturgeon larval drift and dispersal along a 33-km section of the Upper Missouri River to evaluate three main issues: a comparison between multidimensional models and traditional 1-dimensional models, the sensitivity of hydrodynamics to channel morphology, and the implications of channel morphology on retention and transport-time metrics for larval fish. The results indicate that multidimensional models better represent breakthrough curves of transporting larvae compared to 1-dimensional models, especially for the long tail of slow drifters in the population. Results also indicate that channel morphology and hydraulic complexity play significant roles in larval dispersal with certain flow conditions and channel features increasing larval retention and providing potential management options to increase survival rates by adjusting flow conditions during spawning events. For example, modelling indicates increased retention times at discharges 23–38% daily flow exceedance, coincident with emergence of mid-channel sandbars. Findings additionally emphasize the need for improved understanding of biological factors that affect larval drift and dispersal. [ABSTRACT FROM AUTHOR]

Metamorphosis is a critical aspect of coral reef fish ecology. This developmental milestone marks changes in form and function that permit successful transition of pelagic larvae to the demersal lifestyle on coral reefs. However, we know very little about the physiological changes that occur during this period, specifically potential changes in energetics associated with swimming. This is critical, as swimming is the mechanism by which pelagic larvae find a suitable reef on which to settle. Coral grouper larvae (Serranidae: Plectropomas leopardus) were collected at night as they came into the vicinity of a fringing reef to settle, and their physiological metamorphosis was characterized. Larvae and 24 h-settled juveniles were exposed to an endurance swimming test at ecologically relevant swimming speeds, and oxygen uptake rates were measured during activity. To describe how aerobic and anaerobic properties of tissues change during metamorphosis, we also measured whole body citrate synthase and lactate dehydrogenase activity, respectively, as well as mitochondrial density in the trunk and pectoral fins. Our approach accurately measures the oxygen uptake rates these life stages need during the recruitment process, with larvae having a 74% higher mass-specific oxygen uptake rate (ṀO2) than settled juveniles despite swimming at speeds that are only 1.5 body-lengths per second (BLs−1) faster. Citrate synthase activity significantly decreased upon settlement; as larvae had 3.7 times higher activities than juveniles, suggesting that rapid changes in aerobic metabolism of tissues may be an important process during metamorphosis in this species. In contrast, lactate dehydrogenase did not significantly differ upon settlement. These findings highlight some physiological modifications that pelagic coral grouper larvae undertake within 24 h that contribute to successfully settling onto a coral reef. [ABSTRACT FROM AUTHOR]

Rafting has been proposed as an effective mechanism for species without freeliving pelagic larvae to achieve long-distance dispersal, theoretically preventing population differentiation over wide distributional ranges. Moreover, rafting has been advocated as a main dispersal mechanism for marine invertebrates with sub-Antarctic distributions, because of abundant buoyant kelps, driven by the Antarctic Circumpolar Current. Nonetheless, little attention has been given to the role of rafting to establish regular gene flow across the sub-Antarctic, and the geographic and temporal scales at which it occurs. Aiming to unravel these major questions about the extent of genetic connectivity across the Southern Ocean (SO), we studied the pulmonate limpet Siphonaria lateralis, a benthic species with encapsulated larvae, found on the rocky intertidal of sub-Antarctic islands and southern South America. Since S. lateralis is closely associated with D. antarctica, dispersal by rafting is plausible, as revealed by the absence of phylogeographic structure across the sub-Antarctic. We sampled 116 individuals from eight localities across the SO, and used 5,515 SNPs obtained through Genotyping-by-Sequencing, to determine contemporary genetic diversity, structure, and gene flow at two spatial scales; global, across the SO, and regional, within Kerguelen. Results identified substantial genetic structure, differentiating Patagonia, Falklands/Malvinas Islands, South Georgia and the Kerguelen archipelago, and low levels of contemporary gene flow. The most notable genetic differentiation was found between Patagonia/Falklands and South Georgia/Kerguelen. Structure was also significant between Patagonia and the Falkland/Malvinas Islands. Conversely, South Georgia and Kerguelen exhibited closer genetic affinity, and indications of recent but limited gene flow. Moreover, historical gene flow estimates between the four populations were low. At regional scale, noteworthy genetic structure persisted, and gene flow was insufficient to prevent genetic differentiation within Kerguelen. Consequently, rafting's potential may be overestimated as a contemporary mechanism promoting gene flow across the SO, as these events may be sporadic, irregular, and unpredictable for marine invertebrates lacking a larval dispersal stage, since contemporary dispersal events don't seem to facilitate high gene flow at both scales. Accordingly, other oceanographic factors or processes may hinder the establishment of species associated with macroalgae, and as consequence, contemporary genetic connectivity in the sub-Antarctic. [ABSTRACT FROM AUTHOR]

While the interbreeding of Homo neanderthalensis (hereafter Neanderthal) and Anatomically modern human (AMH) has been proven, owing to the shortage of fossils and absence of appropriate DNA, the timing and geography of their interbreeding are not clearly known. In this study, we applied ecological niche modelling (maximum entropy approach) and GIS to reconstruct the palaeodistribution of Neanderthals and AMHs in Southwest Asia and Southeast Europe and identify their contact and potential interbreeding zone during marine isotope stage 5 (MIS 5), when the second wave of interbreeding occurred. We used climatic variables characterizing the environmental conditions of MIS 5 ca. 120 to 80 kyr (averaged value) along with the topography and coordinates of Neanderthal and modern human archaeological sites to characterize the palaeodistribution of each species. Overlapping the models revealed that the Zagros Mountains were a contact and potential interbreeding zone for the two human species. We believe that the Zagros Mountains acted as a corridor connecting the Palearctic/Afrotropical realms, facilitating northwards dispersal of AMHs and southwards dispersal of Neanderthals during MIS 5. Our analyses are comparable with archaeological and genetic evidence collected during recent decades. [ABSTRACT FROM AUTHOR]

For marine species with planktonic dispersal, invasion of open ocean coastlines is impaired by the physical adversity of ocean currents moving larvae downstream and offshore. The extent species are affected by physical adversity depends on interactions of the currents with larval life history traits such as planktonic duration, depth and seasonality. Ecologists have struggled to understand how these traits expose species to adverse ocean currents and affect their ability to persist when introduced to novel habitat. We use a high‐resolution global ocean model to isolate the role of ocean currents on the persistence of a larval‐producing species introduced to every open coastline of the world. We find physical adversity to invasion varies globally by several orders of magnitude. Larval duration is the most influential life history trait because increased duration prolongs species' exposure to ocean currents. Furthermore, variation of physical adversity with life history elucidates how trade‐offs between dispersal traits vary globally. [ABSTRACT FROM AUTHOR]

Gene flow is important for maintaining the genetic diversity required for adaptation to environmental disturbances, though gene flow may be limited by site fidelity in small coastal sharks. Bonnethead sharks (Sphyrna tiburo)—a small coastal hammerhead species—demonstrate site fidelity, as females are philopatric while males migrate to mediate gene flow. Consequently, bonnetheads demonstrate population divergence with distance, and Atlantic populations are genetically distinct from those of the Gulf of Mexico. Indeed, Florida forms a vicariant zone between these two bodies of water for many marine species, including some sharks. However, while bonnetheads are expected to have limited dispersal, the extent and rate of bonnethead migration remain uncertain. Thus, we aimed to determine their dispersal capacity by evaluating connectivity between disparate populations from the Gulf of Mexico and Atlantic Ocean. Using 10,733 SNPs derived from 2bRAD sequences, we evaluated genetic connectivity between Tampa Bay on the Gulf Coast of Florida and Biscayne Bay on the Atlantic coast of Florida. While standard analyses of genetic structure revealed slight but significant differentiation between Tampa Bay and Biscayne Bay populations, demographic history inference based on the site frequency spectrum favored a model without divergence. However, we also estimate that if population divergence occurred, it would have been recent (between 1500 and 4500 years ago), with continuous unidirectional gene flow from Tampa Bay to Biscayne Bay. Our findings support the hypothesis that bonnetheads can migrate over relatively large distances (>300 miles) to find mates. Together, these results provide optimism that under proper management, a small‐bodied globally endangered shark can undergo long migrations to sustain genetic diversity. [ABSTRACT FROM AUTHOR]

I report on long-term patterns of outbreak cycling in four study systems across Canada and illustrate how forecasting in these systems is highly imprecise because of complexity in the cycling and a lack of spatial synchrony amongst sample locations. I describe how a range of bottom-up effects could be generating complexity in these otherwise periodic systems. (1) The spruce budworm in Québec exhibits aperiodic and asynchronous behavior at fast time-scales, and a slow modulation of cycle peak intensity that varies regionally. (2) The forest tent caterpillar across Canada exhibits eruptive spiking behavior that is aperiodic locally, and asynchronous amongst regions, yet aggregates to produce a pattern of periodic outbreaks. In Québec, forest tent caterpillar cycles differ in the aspen-dominated northwest versus the maple-dominated southeast, with opposing patterns of cycle intensity between the two regions. (3) In Alberta, forest tent caterpillar outbreak cycles resist synchronization across a forest landscape gradient, even at very fine spatial scales, resulting in a complex pattern of cycling that defies simple forecasting techniques. (4) In the Border Lakes region of Ontario and Minnesota, where the two insect species coexist in a mixedwood landscape of hardwood and conifers, outbreak cycle intensity in each species varies spatially and temporally in response to host forest landscape structure. Much attention has been given to the effect of top-down agents in driving synchronizable population cycles. However, foliage loss, tree death, and forest succession at stem, stand, and landscape scales affect larval and adult dispersal success, and may serve to override regulatory processes that cause otherwise top-down-driven periodic, synchronized, and predictable population oscillations to become aperiodic, asynchronous, and unpredictable. Incorporating bottom-up effects at multiple spatial and temporal scales may be the key to making significant improvements in forest insect outbreak forecasting. [ABSTRACT FROM AUTHOR]

Signals of natural selection can be quickly eroded in high gene flow systems, curtailing efforts to understand how and when genetic adaptation occurs in the ocean. This long‐standing, unresolved topic in ecology and evolution has renewed importance because changing environmental conditions are driving range expansions that may necessitate rapid evolutionary responses. One example occurs in Kellet's whelk (Kelletia kelletii), a common subtidal gastropod with an ~40‐ to 60‐day pelagic larval duration that expanded their biogeographic range northwards in the 1970s by over 300 km. To test for genetic adaptation, we performed a series of experimental crosses with Kellet's whelk adults collected from their historical (HxH) and recently expanded range (ExE), and conducted RNA‐Seq on offspring that we reared in a common garden environment. We identified 2770 differentially expressed genes (DEGs) between 54 offspring samples with either only historical range (HxH offspring) or expanded range (ExE offspring) ancestry. Using SNPs called directly from the DEGs, we assigned samples of known origin back to their range of origin with unprecedented accuracy for a marine species (92.6% and 94.5% for HxH and ExE offspring, respectively). The SNP with the highest predictive importance occurred on triosephosphate isomerase (TPI), an essential metabolic enzyme involved in cold stress response. TPI was significantly upregulated and contained a non‐synonymous mutation in the expanded range. Our findings pave the way for accurately identifying patterns of dispersal, gene flow and population connectivity in the ocean by demonstrating that experimental transcriptomics can reveal mechanisms for how marine organisms respond to changing environmental conditions. [ABSTRACT FROM AUTHOR]

Computing Lagrangian trajectories with ocean circulation models is a powerful way to infer larval dispersal pathways and connectivity. Defining release areas and timing of particles to represent larval habitat realistically is critical to obtaining representative dispersal pathways. However, it is challenging due to spatial and temporal variability in larval density. Forward-tracking particle experiments were conducted to study larval connectivity of four species (neritic or mesopelagic) in the Gulf of Mexico's (GoM) deep-water region. A seasonal climatology coupled with predicted potential larval habitat models based on generalized additive models was used to delimit the particle dispersal origin. Two contrasting mesoscale circulation patterns were examined: (1) high Loop Current (LC) intrusion, absence of recently detached LC anticyclonic eddies (LC-ACE), and no interaction between LC-ACEs and the semi-permanent cyclonic eddy (CE) in the Bay of Campeche (BoC), and (2) limited LC intrusion, a recently detached LC-ACE, and interaction between LC-ACEs and the BoC's CE. To simulate larval transport, virtual larvae were randomly released in the potential habitats and advected for 30 days with the velocity fields of the HYbrid Coordinate Ocean Model with hourly-resolution assimilation. Potential habitat location and size played a major role in dispersal and connectivity. A greater percentage of particles were retained in potential habitats restricted to the southern BoC, suggesting lower connectivity with other GoM regions than those encompassing most of the BoC or the central Gulf. Mesoscale feature interactions in the western GoM and BoC led to greater dispersion along the western basin. By contrast, the absence of ACE-CE interaction in the BoC led to greater retention and less connectivity between the southern and northern GoM. Under high LC intrusion, particles seeded north of the Yucatan Shelf were advected through the Florida Straits and dispersed within the GoM. Coupling potential habitat models with particle experiments can help characterize the dispersal and connectivity of fish larvae in oceanic systems. [ABSTRACT FROM AUTHOR]

Many coastal marine species have discontinuous distributions or genetic breakpoints throughout their geographical ranges. These spatial and genetic disjunctions occur in species that span limited to broad dispersal potential. Thus, the mechanisms that underlie these disjunctions remain speculative or incompletely known, particularly on small spatial scales where long-term historical processes are unlikely to be the only mechanism contributing to disjunction. Rather, ecological or oceanographic factors may be important. To identify key drivers of coastal disjunctions, we reviewed publications investigating spatial and genetic disjunctions in coastal marine species and visually summarized where and why they are thought to occur. The most frequently cited mechanisms implicated in causing disjunctions include historical processes, oceanographic features, heterogeneous habitat, species introductions, and limited larval dispersal capacities. However, the relative importance of each of these processes varies depending on the spatial scales investigated. Furthermore, locations associated with disjunctions for a suite of species are typically associated with multiple processes that maintain these disjunctions. This study provides a non-exhaustive synthesis of disjunctions in coastal marine species by visualizing where they occur, exploring underlying mechanisms, and investigating biases in how the scientific community studies this phenomenon. [ABSTRACT FROM AUTHOR]

Most ecological studies attempting to understand causes of population dynamics and community structure disregard intraspecific trait variation. We quantified the importance of natural intra‐cohort variation in body size and density of juveniles for recruitment of a sessile marine organism, the barnacle Semibalanus balanoides. Barnacles are representative of species organised in metapopulations, that is, as open local populations connected by larval dispersal. We tracked the individual growth and survival of a cohort of juvenile barnacles from two shores of North Wales. Barnacles settled as larvae in spring of 2002 on previously cleared rock. The density of these new recruits was experimentally manipulated in June and randomly selected individuals were monitored from June to October to evaluate the role of barnacle size and density in predicting survival. In doing so we characterised density at three spatial scales (quadrat: 25 cm2, cells within quadrats: 25 mm2 and neighbourhood: number of neighbours in physical contact with the target barnacle). At all scales, variations in juvenile body size exacerbated the effect of density‐dependent mortality on population size. While density‐dependent mortality was very intense in the small‐sized individuals, large‐sized individuals experienced very weak density‐dependent mortality and showed high survival rates. Using the concept of 'Jensen inequality', we show that important biases in estimations of survival, based on population size only, occur at high barnacle densities, where survival is low. Our study highlights the role of body size variation in understanding dynamics of open populations. [ABSTRACT FROM AUTHOR]

The buffer zones between urban protected areas (UPAs) and their cities play a significant role in managing and protecting UPAs. However, they are also the frontier of conflicts due to complex functionality and a large number of stakeholders. Besides ensuring the buffer zone's function of protecting the UPA, it is also vital to understand how it can fulfill the diverse needs of multiple interest groups residing in or utilizing this area. To address the significant social science research gap in UPA buffer zone management, we establish a conceptual framework and explore how the public's overall satisfaction with the buffer depends on five essential buffer zone qualities, namely environmental quality, connectivity, infrastructure, cultural, and visual quality. We focus on China's Urban Scenic and Historic Areas (USHA), a major type of UPA with high cultural, social, and esthetic values. Using the buffer of Shugang-Slender West Lake Scenic and Historic Area in Yangzhou City as the case study, we conducted intercept and online surveys (n = 499), investigating the perceptions of three user groups—residents, businesses, and tourists. The results indicate high overall satisfaction for all three groups. Environmental, visual, and cultural qualities were rated higher than connectivity and infrastructure quality. Residents generally showed the highest satisfaction and tourists the lowest. For all three groups, environmental quality, connectivity, and infrastructure quality significantly influenced overall satisfaction, while cultural and visual quality did not. This suggests that the public expects the buffer zone to serve as high-quality multi-functional open spaces that enhance the quality of life while providing recreation, service, and transportation functions. Besides direct planning and management advice to China's UPAs and other countries with similar contexts, our study offers a transferable framework for incorporating social perceptions and highlights their significance in informing the functional planning of UPA buffer zones for public welfare. [ABSTRACT FROM AUTHOR]