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Subfossil remains of the Quaternary megafauna from two Ukrainian natural history collections stored at Kaniv Nature Reserve and the National Museum of Natural History NAS of Ukraine were examined. Most of the bones were collected in 1965–1966, in the building pit and the gateway of the Kaniv hydroelectric power plant. The fauna is represented at least by ten taxa (Gulo gulo, Mammuthus trogonterii chosaricus, Mammuthus intermedius, Coelodonta antiquitatis, Megaloceros giganteus, Alces alces, Bison priscus, Cervus elaphus, Capra cf. ibex, and Equus ferus). Skeletal parts are represented mainly by skulls, long bones, horns, and tusks. Based on the species composition of proboscideans, at least part of the faunal assemblage is dated by the end of the Middle Pleistocene (Dnieper Stage = Saale, Warta, MIS 6), but majority of bones could be older or younger (Late Pleistocene and Holocene age) due to the alluvial origin of accumulation.

The Bering Land Bridge connecting North America and Eurasia was periodically exposed and inundated by oscillating sea levels during the Pleistocene glacial cycles. This land connection allowed the intermittent dispersal of animals, including humans, between Western Beringia (far north-east Asia) and Eastern Beringia (north-west North America), changing the faunal community composition of both continents. The Pleistocene glacial cycles also had profound impacts on temperature, precipitation, and vegetation, impacting faunal community structure and demography. While these palaeoenvironmental impacts have been studied in many large herbivores from Beringia (e.g., bison, mammoths, horses), the Pleistocene population dynamics of the diverse guild of carnivorans present in the region are less well understood, due to their lower abundances. In this study, we analyse mitochondrial genome data from ancient brown bears (Ursus arctos; n = 103) and lions (Panthera spp.; n = 39), two megafaunal carnivorans that dispersed into North America during the Pleistocene. Our results reveal striking synchronicity in the population dynamics of Beringian lions and brown bears, with multiple waves of dispersal across the Bering Land Bridge coinciding with glacial periods of low sea levels, as well as synchronous local extinctions in Eastern Beringia during Marine Isotope Stage 3. The evolutionary histories of these two taxa underscore the crucial biogeographic role of the Bering Land Bridge in the distribution, turnover, and maintenance of megafaunal populations in North America.

The extinction of large-bodied terrestrial ‘megafauna’ during earlier phases of the Quaternary had a significant impact on the transforming structure of ecosystems. However, the causes of such losses remains difficult to determine in part because of a paucity of reliable geochronological information about the taxa involved. This is especially true for continents such as Australia where the majority of extinct species have never been dated using radiometric and/or luminescence methods. Here we add new understanding about the geochronology of the world's largest-ever marsupial, the giant wombat-like Diprotodon optatum, an iconic member of the large herbivore guild of Pleistocene Australia. We present 28 new direct U-series ages (dentine) and 10 luminescence ages (sediments) for D. optatum fossils from three sites in tropical north and subtropical eastern Australia. The luminescence ages lie close to saturation for the tropical northern site of Floraville and therefore indicate minimum ages, and sediments from Gowrie Creek in the Darling Downs were mixed and can only be stated as a likely age range. Nevertheless the results assist in our broader understanding of the timing of persistence of the species. Our results demonstrate that the species roamed the northern tropics at least until the mid-Pleistocene (ca. 420 ka). They likely remained widespread during Marine Isotope Stage 5 (ca. 110 ka) and were abundant on the Darling Downs of eastern Australia. The youngest of the new ages that we report (ca. 60 ka) are from Neds Gully on the Darling Downs, a catchment previously considered by some to contain among the last survivors of the now-extinct megafauna. The new dated record demonstrates that deposits of varying ages occur within the catchment. Consequently, existing species lists that treat Neds Gully as a single faunal assemblage are likely significantly time-averaged and overinflated in terms of palaeo-diversity.

An individual whale shark (Rhincodon typus) was recorded on January 15, 2020, during the marine megafauna drone-monitoring. The animal was filmed for approximately 400 m of swimming at an average speed of 4.8 km/h, 650 m southwest of the mouth of a river impacted by the rupture of a mining tailing dam 5 years ago. The whale shark is a filter-feeding and highly migratory species. This is a rare record of this threatened species, representing the importance of recovering and protecting biodiversity in the Rio Doce river mouth region.

The Ganges River Dolphin (Platanista gangetica) is the most charismatic aquatic species inhabiting rivers of India, Bangladesh, and Nepal. It is an endangered species that occurs both in the Brahmaputra and Barak river systems in Assam (India). In the Brahmaputra river system, the occurence of ‘hihu’ is primarily confirmed in the mainstream Brahmaputra, the Kulsi river of Kamrup district, and the Subansiri river of Lakhimpur district. The dolphins inhabit river confluences or tributary junctions followed by river meanderings with the prevalence of eddy counter-currents and prey-fish abundance. Of late, it has been observed that river dolphin population has declined at an alarming rate due to the potential threats including poaching for dolphin oil, by-catch, overfishing, net entanglements, sand mining, habitat destruction through aquatic pollution, construction of dams, and lack of awareness. The species is left only in certain pockets of the Brahmaputra River. Thus, there is an urgent need for the conservation of this endangered species in its natural habitats. Effective protection of this endangered aquatic megafauna requires elimination and management of the potential threats. This review provides an overview of the distribution and population status, ecology, and management strategies and recommendation to increase awareness for its long-term conservation.

Proboscideans were keystone Cenozoic megaherbivores and present a highly relevant case study to frame the timing and magnitude of recent megafauna extinctions against long-term macroevolutionary patterns. By surveying the entire proboscidean fossil history using model-based approaches, we show that the dramatic Miocene explosion of proboscidean functional diversity was triggered by their biogeographical expansion beyond Africa. Ecomorphological innovations drove niche differentia- tion; communities that accommodated several disparate proboscidean species in sympatry became commonplace. The first burst of extinctions took place in the late Miocene, approximately 7 million years ago (Ma). Importantly, this and subsequent extinction trends showed high ecomorphological selectivity and went hand in hand with palaeoclimate dynamics. The global extirpation of proboscideans began escalating from 3 Ma with further extinctions in Eurasia and then a dramatic increase in African extinctions at 2.4 Ma. Overhunting by humans may have served as a final double jeopardy in the late Pleistocene after climate-triggered extinction trends that began long before hominins evolved suitable hunting capabilities., This work was supported by the Talent Attraction Program of the Madrid Government (no. 2017-T1/AMB5298), the German Research Foundation (AOBJ no. 637491) and the Academy of Finland (post-doctoral research fund no. 315691).

Litter in the marine environment, in particular plastic, is a significant threat to marine megafauna. Cetaceans are known to ingest or become entangled in marine debris, likely impacting individuals and populations. Southeast Asia is a biodiversity hotspot and harbours a diverse cetacean assemblage. However, there are key knowledge gaps relating to the impact of litter in this region due the lack of experts to survey its vast coastlines. This study aims to address such gaps by using social media, gathering data from Facebook posts relating to cetacean strandings and litter across Southeast Asia between 2009 and 2019. Results show that at least 15 cetacean species have been negatively affected by litter, with ingestion most commonly affecting deep-diving species. Epipelagic and mesopelagic foragers were most vulnerable to entanglement. Davao in the Philippines was identified as a litter-related stranding hotspot. The Irrawaddy dolphin (Orcaella brevirostris) and pygmy sperm whale (Kogia breviceps) are particularly vulnerable to litter. The combination of social media and peer reviewed literature can help build a more complete picture of the spatial distribution of marine litter and the scale of the impact it has on cetacean populations. In this study we provide details of a valuable online tool for helping to understand the impact of marine litter on cetaceans and other charismatic species that are a focus of community engagement.

Climatic and environmental changes, as well as human action, have been cited as potential causes for the extinction of megafauna in South America at the end of the Pleistocene. Among megamammals lineages with Holarctic origin, only horses and proboscideans went extinct in South America during this period. This study aims to understand how the spatial extent of habitats suitable for Equus neogeus and Notiomastodon platensis changed between the last glacial maximum (LGM) and the middle Holocene in order to determine the impact that climatic and environmental changes had on these taxa. We used species distribution modeling to estimate their potential extent on the continent and found that both species occupied arid and semiarid open lands during the LGM, mainly in the Pampean region of Argentina, southern and northeastern Brazil, and parts of the Andes. However, when climate conditions changed from dry and cold during the LGM to humid and warm during the middle Holocene, the areas suitable for these taxa were reduced dramatically. These results support the hypothesis that climatic changes were a driving cause of extinction of these megamammals in South America, although we cannot rule out the impact of human actions or other potential causes for their extinction.

Objectives Gigantopithecus blacki, the largest hominoid known, is one of the representative Pleistocene mammals in southern China and northern Southeast Asia. Here we investigate the feeding ecology of G. blacki in its core habitat (Guangxi, Southern China) during the early Early Pleistocene, which was the early period in its evolution. Materials and methods The stable isotopic (C, O) analysis of tooth enamel of the fauna associated with G. blacki (n = 58), including the largest number of G. blacki teeth (n = 12) to date from the Liucheng Gigantopithecus Cave (~2 Ma), Guangxi, China, is undertaken. Results The δ13 C values of Liucheng fauna range from -12.9 to -19.0‰ with an average of -16.1 ± 1.3‰ (n = 58) and the δ18 O values range from -4.3 to -9.6‰ with an average of -6.9 ± 1.2‰ (n = 58). The δ13 C values of G. blacki range from -15.9‰ to -17.0‰ with an average of -16.5 ± 0.4‰ (n = 12), and the δ18 O values vary from -5.9‰ to -7.5‰ with an average of -6.6 ± 0.5‰ (n = 12). Conclusions The isotopic data show Guangxi was characterized by closed C3 forest and humid climate in the early Early Pleistocene. Niche partitioning is found among G. blacki, Sinomastodon, Ailuropoda and Stegodon, the typical megafauna in South China in the early Early Pleistocene. This could be one of the important factors for them to co-exist until the Middle Pleistocene. Smallest isotopic variations of G. blacki are found compared with those of contemporary animals, indicating a conservative foraging ecology i.e., limited foraging area and/or narrow dietary flexibility. Furthermore, the more confined foraging ecology of G. blacki is also seen in comparison with fossil and extant large-bodied primates. However, the unique dietary pattern of G. blacki does not seem to have hindered its survival. The environment in Guangxi during the early Early Pleistocene offered the suitable conditions for G. blacki to become one of the typical species in the faunal assemblages.

Mutualism is a form of symbiosis whereby both parties benefit from the relationship. An example is cleaning symbiosis, which has been observed in terrestrial and marine environments. The most recognized form of marine cleaning symbiosis is that of cleaner fishes and their clients.Cleaner species set up cleaning stations on the reef, and other species seek out their services. However, it is not well understood how the presence of cleaning stations influence movements of large highly mobile species. We examined the role of cleaning stations as a driver of movement and habitat use in a mobile client species.Here, we used a combination of passive acoustic telemetry and in‐water surveys to investigate cleaning station attendance by the reef manta ray Mobula alfredi. We employed a novel approach in the form of a fine‐scale acoustic receiver array set up around a known cleaning area and tagged 42 rays. Within the array, we mapped structural features, surveyed the distribution of cleaner wrasse, and observed the habitat use of the rays.We found manta ray space use was significantly associated with blue‐streak cleaner wrasse Labroides dimidiatus distribution and hard coral substrate. Cleaning interactions dominated their habitat use at this site, taking precedence over other life history traits such as feeding and courtship.This study has demonstrated that cleaning symbiosis is a driver for highly mobile, and otherwise pelagic, species to visit inshore reef environments. We suggest that targeted and long‐term use of specific cleaning stations reflects manta rays having a long‐term memory and cognitive map of some shallow reef environments where quality cleaning is provided. We hypothesize that animals prefer cleaning sites in proximity to productive foraging regions., This study investigates the role of mutualism in determining site selection in marine megafauna. The aim was to determine the role of cleaning stations as a driver of movement and habitat use in a mobile client species. Through a combination of in‐water observations and a novel application of fine‐scale passive acoustic tracking, we demonstrated that cleaning symbiosis is a driver for highly mobile, and otherwise pelagic species to visit inshore reef environments. We suggest that targeted and long‐term use of specific cleaning stations reflects manta rays having a long‐term memory and cognitive map of some shallow reef environments where quality cleaning is provided. We hypothesize that animals preference cleaning sites in proximity to productive foraging regions.

Monitoring large marine mammals is challenging due to their low abundances in general, an ability to move over large distances and wide geographical range sizes.The distribution of the pygmy (Kogia breviceps) and dwarf (Kogia sima) sperm whales is informed by relatively rare sightings, which does not permit accurate estimates of their distribution ranges. Hence, their conservation status has long remained Data Deficient (DD) in the Red list of the International Union for Conservation of Nature (IUCN), which prevent appropriate conservation measures.Environmental DNA (eDNA) metabarcoding uses DNA traces left by organisms in their environments to detect the presence of targeted taxon, and is here proved to be useful to increase our knowledge on the distribution of rare but emblematic megafauna.Retrieving eDNA from filtered surface water provides the first detection of the Dwarf sperm whale (Kogia sima) around the remote Malpelo island (Colombia).Environmental DNA collected during oceanic missions can generate better knowledge on rare but emblematic animals even in regions that are generally well sampled for other taxa., Retrieving eDNA from filtered surface water provides the first detection of the Dwarf sperm whale (Kogia sima) around the remote Malpelo island (Colombia).

The earliest appearance of elk/wapiti (Cervus canadensis) in eastern North America is not thoroughly documented due to the small number of directly dated remains. Until recently, no absolute dates on elk bone older than 10,000 14C yr BP (11,621 to 11,306 calibrated years (cal yr) BP) were known from this region. The partial skeleton of the Tope Elk was discovered in 2017 during commercial excavation of peat deposits from a small bog in southeastern Medina County, Ohio, United States. Subsequent examination of the remains revealed the individual to be a robust male approximately 8.5 years old at death. The large size of this individual is compared with late Holocene specimens and suggests diminution of elk since the late Pleistocene. Two accelerator mass spectrometry (AMS) radiocarbon assays on bone collagen samples taken from the scapula and metacarpal of this individual returned ages of 10,270 ± 30 14C yr BP (Beta-477478) (12,154 to 11,835 cal yr BP) and 10,260 ± 30 14C yr BP (Beta-521748) (12,144 to 11,830 cal yr BP), respectively. These results place Cervus canadensis in the terminal Pleistocene of the eastern woodlands and near the establishment of the mixed deciduous forest biome over much of the region. This early temporal placement also situates this early elk as closely following the last representatives of now-extinct megafauna such as the American mastodon (Mammut americanum) and contemporary with the Late Paleoindian inhabitants of the region.

An extinct thermophile European water buffalo Bubalus murrensis was recorded in the interglacials of the Middle and Late Pleistocene in Central and Western Europe. The species was unknown after the Eemian Interglacial (c. 123 ka) there and have never been found in Eastern Europe. Here we report on an unexpected record of this exotic species in the center of East European Plain near the Kolomna town (Moscow Region) more than 110 millennia later, in the Bolling – Allerod warming of the Last glacial. The unique paleontological discovery of the last European water buffalo in the center of Eastern Europe occupied mainly by a cold adapted so-called ‘Mammoth fauna’ allow us to discuss this unusual occurrence in paleoenvironmental context and suggest the model of dispersal and final extinction of the species. Based on recent integrated studies, we show that the species could persist in the Ponto-Caspian region and then spread northwards during the last Late Pleistocene warming. Main factors of its extinction could be the rapid global climatic changes and strong regional paleoenvironmental instability as well as increasing activity of Upper Paleolithic hunters. The discovery is important in the context of the late Quaternary megafaunal extinctions and a recent phenomenon of global warming.

Records of Pleistocene reptiles are relatively well known in different countries. However, reptile fossil records of Pleistocene from Latin America are scarce and limited to presence data associated with records of megafauna remains. Taphonomic studies in Pleistocene reptiles are focused on finding out the origin of the paleontological remains; that is, if the remains found at a particular place correspond to organisms that lived and died there or if they were carried out and deposited there by water currents or predators. Pleistocene reptiles have been used as a proxy for qualitative paleoclimatic reconstructions of localities. In this study, we describe the fossil record of squamate reptiles from the Pleistocene of San Jose Buenavista (Puebla, Mexico), and the taphonomic relationship between them and the associated megafauna, as well as reconstruct the paleoclimate of the paleontological site in Central Mexico where the remains were found. We present the first Mexican Pleistocene record of Anolis and Storeria, the third fossil record of the alligator lizard Barisia sp. in Mexico, and the first North American Pleistocene record for the rattlesnake Crotalus triseriatus. The rattlesnake (C. triseriatus) was found inside the mandible of the American mastodon (Mammut americanum). This finding suggests that the mastodon remains were used as burrow by the rattlesnake during the Pleistocene. Paleoclimate was reconstructed using the Mutual Ecogeographic Range method, which uses the distribution and climate niche of the nearest extant representatives of the identified fossil taxa. A mean annual temperature of 13.91 ± 1.54 °C and an annual precipitation of 964.04 ± 316.82 mm were inferred for the locality. This suggests that the assemblage of fossil species found inhabited the locality during a glacial period.

Proboscideans arrived in South America from North America during the Great American Biotic Interchange, becoming one of the most representative animals of the megafauna that inhabited this continent throughout the Quaternary. In Colombia, the abundance of their remains contrasts with scarce scientific descriptions and publications. This paper identifies dental and postcranial proboscidean fossils from the Center and Northeast of Colombia. The fossil remains were identified as molars (six), a tusk, cervical vertebrae, and a distal part of the right humerus. The tusk was assigned to Notiomastodon platensis, while the other remains were assigned to Gomphotheriidae, with at least six individuals: two immatures, two subadults, and two older adults – mature and senile. Keywords: South America, megamammals, taxonomy, Gomphotheriidae, Notiomastodon platensis.

Elephants have profound effects on the functioning of the ecosystems they inhabit. Little is known, however, about the role of Asian elephants (Elephas maximus) as agents of seed dispersal in tropical rainforests of Southeast Asia, particularly in the Sundaland region. Sundaic forests are peculiar in their phenology, with supra-annual and highly irregular episodes of mast fruiting. Here I present a long-term (73-month) monitoring of the seeds dispersed by elephants in dipterocarp forests of northern Peninsular Malaysia. I conducted monthly dung surveys in two mineral licks (11.3 km apart) frequently visited by elephants. Additionally, I recorded haphazard observations of seeds and seedlings in elephant dung. I recorded a minimum of 45 morphospecies from at least 25 plant families dispersed by elephants. Elephant seed dispersal varies spatially, with only 39.4% of the morphospecies dispersed at both sites (Jaccard dissimilarity index = 0.45). Temporally, elephants dispersed seeds in sporadic pulses in terms of abundance and diversity, without any apparent seasonality (seeds appeared in 19.1 % of 1,284 dung piles and 49.3 % of 73 months sampled). Around 14 morphospecies exhibited the two types of megafaunal syndrome traits defined by Guimaraes et al. (2008). However, another 11 morphospecies were found to conform to a Type 3 trait; species with large fruits and moderately large (> 1.5 cm) seeds in moderately large numbers (> 15). This makes the total of 24 morphospecies exhibiting megafaunal syndrome traits. However, the current definition is over simplified, and a new definition is needed that expands beyond physical fruit traits. Over half (53%) of the plants dispersed by elephants exhibit the megafaunal dispersal syndrome, suggesting a higher level of specialized elephant-plant seed dispersal interactions than previously assumed in Asia. Sundaland’s forests are undergoing a rapid loss of their rich megafaunal assemblages, with profound and long-term consequences for their function.

The study of faecal samples to reconstruct the diets and habitats of extinct megafauna has traditionally relied on pollen and macrofossil analysis. DNA metabarcoding has emerged as a valuable tool to complement and refine these proxies. While published studies have compared the results of these three proxies for sediments, this comparison is currently lacking for permafrost preserved mammal faeces. Moreover, most metabarcoding studies have focused on a single plant-specific DNA marker region. In this study, we target both the commonly used chloroplast trnL P6 loop as well as nuclear ribosomal ITS (nrITS). The latter can increase taxonomic resolution of plant identifications but requires DNA to be relatively well preserved because of the target length (∼300–500 bp). We compare DNA results to pollen and macrofossil analyses from permafrost and ice-preserved faeces of Pleistocene and Holocene megafauna. Samples include woolly mammoth, horse, steppe bison as well as Holocene and extant caribou. Most plant identifications were found using DNA, likely because the studied faeces contained many vegetative remains that could not be identified using macrofossils or pollen. Several taxa were, however, identified to lower taxonomic levels uniquely with macrofossil and pollen analysis. The nrITS marker provides species level taxonomic resolution for commonly encountered plant families that are hard to distinguish using the other proxies (e.g. Asteraceae, Cyperaceae and Poaceae). Integrating the results from all proxies, we are able to accurately reconstruct known diets and habitats of the extant caribou. Applying this approach to the extinct mammals, we find that the Holocene horse and steppe bison were not strict grazers but mixed feeders living in a marshy wetland environment. The mammoths showed highly varying diets from different non-analogous habitats. This confirms the presence of a mosaic of habitats in the Pleistocene ‘mammoth steppe’ that mammoths could fully exploit due to their flexibility in food choice.

Sloths and ground sloths (Xenarthra: Tardigrada) are among the most conspicuous mammals in the Cenozoic faunas of South America. During the late Pleistocene and the early Holocene, all the megafaunal xenarthrans became extinct. While much attention has been paid to understanding the causes of megafauna extinction, less attention has been given to understanding the impacts of the loss of the megafauna on other organisms with whom they interacted. Paleoparasitology offers the opportunity to look back into the past and observe directly how parasites responded to environmental change and host decline events. The present work is the first paleoparasitological study on megaherbivores dung from the archaeological site Cueva Huenul 1 (northwestern Patagonia, Argentina). Twenty one dung samples were examined for parasites. Samples were processed by rehydration in a 0.5% water solution of trissodium phosphate, followed by homogenization, filtered and processed by spontaneous sedimentation. Additionally, microhistological analyses of three samples were made. The dung samples were identified as belonging to a ground sloth. Ground sloths from northwestern Patagonia were infected by the nematodes Trichostrongylus sp., Nematodirus sp., at least three Strongylida-type species, Trichuris sp., one ascaridid and one unidentified nematode. Also, the results indicated that the diet was mainly based on shrub species (Schinus johnstonii, Prosopis sp., Berberis empetrifolia, Ephedra chilense and Retanilla patagonica), typical of the Monte vegetation. Also, the cacti Maihuenia and the grasses Festuca kurtziana, Hordeum comosum, Stipa speciosa and Poa sp. (Family Poaceae) were found but in less frequency. The host-parasite-environment interactions, the potential parasitic diseases and ecological consequences of the ground sloth extinction are discussed. This study shows the potential of paleoparasitological studies of ancient feces to contribute to the understanding of the evolutionary histories of parasites and hosts.

A new Pleistocene site in the Pabbi Hills of Pakistan, and deposits to the east near Bhimbar provide important additions to the Upper Siwalik fauna of South Asia. The mammalian fauna of 10 species from Panjan Sher Shahana at the southwestern tip of the Pabbi Hills is a rich mammalian assemblage dating to the early to Middle Pleistocene of the Upper Siwalik Subgroup. The Panjan Sher Shahana assemblage shows strong resemblance to other Pleistocene faunas of the Siwalik Group from the Indian subcontinent. The new site is dominated by Bovidae and Equus. Among megafauna, two species of Elephas, commonly found in the Upper Siwaliks, are associated with the uncommon Stegodon in Pabbi Hills. These and other elements of the Panjan Sher Shahana fauna are treated briefly here. The Late Neogene deposits of Bhimbar, 30 km east of Jhelum, appear to represent a similar succession equivalent to the Pleistocene (“Pinjor”) fauna and produce important new elements, including a rare record of the bamboo rat Anepsirhizomys opdykei.

Plastic pollution is increasing rapidly throughout the world’s oceans and is considered a major threat to marine wildlife and ecosystems. Although known to cause lethal or sub-lethal effects to vulnerable marine megafauna, population-level impacts of plastic pollution have not been thoroughly investigated. Here, we compiled and evaluated information from peer-reviewed studies that reported deleterious individual-level effects of plastic pollution on air-breathing marine megafauna (i.e. seabirds, marine mammals, and sea turtles) worldwide, highlighting those that assessed potential population-level effects. Lethal and sub-lethal individual-level effects included drowning, starvation, gastrointestinal tract damage, malnutrition, physical injury, reduced mobility, and physiological stress, resulting in reduced energy acquisition and assimilation, compromised health, reproductive impairment, and mortality. We found 47 studies published between 1969 and 2020 that considered population-level effects of plastic entanglement (n = 26), ingestion (n = 19), or both (n = 2). Of these, 7 inferred population-level effects (n = 6, entanglement; n = 1, ingestion), whereas 19 lacked evidence for effects (n = 12, entanglement; n = 6, ingestion; n = 1, both). However, no study in the past 50 yr reported direct evidence of population-level effects. Despite increased interest in and awareness of the presence of plastic pollution throughout the world’s oceans, the extent and magnitude of demographic impacts on marine megafauna remains largely unassessed and therefore unknown, in contrast to well-documented effects on individuals. Addressing this major assessment gap will allow researchers and managers to compare relative effects of multiple threats—including plastic pollution—on marine megafauna populations, thus providing appropriate context for strategic conservation priority-setting.

1. The mahseer (Tor spp.) fishes of South and Southeast Asia are iconic megafaunal species that are highly valued by recreational anglers. Knowledge on their populations is limited due to the challenges associated with sampling these large bodied fishes (>50kg) in remote monsoonal rivers. Despite its global iconic status among recreational anglers, the hump-backed mahseer of South India’s River Cauvery lacked a valid scientific name and was on a trajectory towards extinction until its rapidly declining population status was established by analyses of angler catch records. 2. Angling records from 1998 to 2012 revealed that mahseer catch rates had increased in the period. The resulting publication in Aquatic Conservation (AQC) highlighted the positive role of catch-and-release angling in providing information on data-poor species. However, further analyses revealed these catches comprised of not one but two distinct phenotypes. Prior to 1993, all mahseer captured were hump-backed; since then, a blue-fin phenotype appeared in catches and subsequently dominated them. These results triggered further studies that revealed the hump-backed mahseer was the endemic Tor remadevii and the blue-fin was the invasive Tor khudree that had been introduced in 1976 and then stocked periodically from hatcheries. 3. The initial AQC publication successfully demonstrated the high value of organised angling as a monitoring tool for data-poor fishes and its application to assessing the temporal population patterns of large bodied fishes in monsoonal rivers. It was also the catalyst for initiating subsequent studies on T. remadevii that, in entirety, enabled its recent assessment as ‘Critically Endangered’ on the IUCN Red List. In the absence of the AQC paper, and the subsequent studies it triggered, it is highly probable that the species would have remained on a trajectory towards rapid extinction. Instead, the first major steps to safeguarding its future have been taken.

The Revillagigedo Archipelago National Park is the largest no-take Marine Protected Area in North America and it is essential for the conservation of globally endangered marine megafauna, including cetaceans, sea birds and cartilaginous fishes. The present paper reports the occurrence of 28 chondrichthyan species, including 19 sharks, seven batoids and two chimaeras in the Revillagigedo Archipelago, comprising eight new records and a brief revision of confirmed species to date.

A growing body of literature proposes that our ancestors contributed to large mammal extinctions in Africa long before the appearance ofHomo sapiens, with some arguing that premodern hominins (e.g.,Homo erectus) triggered the demise of Africa's largest herbivores and the loss of carnivoran diversity. Though such arguments have been around for decades, they are now increasingly accepted by those concerned with biodiversity decline in the present-day, despite the near complete absence of critical discussion or debate. To facilitate that process, here we review ancient anthropogenic extinction hypotheses and critically examine the data underpinning them. Broadly speaking, we show that arguments made in favor of ancient anthropogenic extinctions are based on problematic data analysis and interpretation, and are substantially weakened when extinctions are considered in the context of long-term evolutionary, ecological, and environmental changes. Thus, at present, there is no compelling empirical evidence supporting a deep history of hominin impacts on Africa's faunal diversity.

Background Argos satellite telemetry is used globally to track terrestrial and aquatic megafauna, yet the accuracy of this system has been described empirically only for a limited number of species. We used Argos-linked archival tags with Fastloc GPS deployed on free-ranging sperm (Physeter macrocephalus), blue (Balaenoptera musculus), and fin (B. physalus) whales to derive empirical estimates of Argos location errors for these species, examine possible behavior-related differences, and test the effect of incorporating species-specific error parameters on performance of a commonly used movement model. Results Argos location errors for blue and fin whale tags were similar and were combined (n = 1712 locations) for comparison against sperm whale tags (n = 1206 locations). Location error magnitudes for tags attached to sperm whales were significantly larger than blue/fin whale tags for almost all Argos location classes (LC), ranging from 964 m versus 647 m for LC 3, respectively, to 10,569 m versus 5589 m for LC B, respectively. However, these differences were not seen while tags floated at the surface after release. Sperm whale tags were significantly colder than ambient temperature when surfacing from a dive, compared to blue/fin whale tags (16.9 °C versus 1.3 °C, respectively) leading to larger changes in tag temperature during post-dive intervals. The increased rate of tag temperature change while at the surface was correlated to increased error magnitude for sperm whales but not blue/fin whales. Movement model performance was not significantly improved by incorporating species-specific error parameters. Conclusions Location accuracy estimates for blue/fin whales were within the range estimated for other marine megafauna, but were higher for sperm whales. Thermal inertia from deep, long-duration dives likely caused transmission frequency drift and greater Argos location error in sperm whales, as tags warmed at the surface during post-dive intervals. Thus, tracks of deep-diving species may be less accurate than for other species. However, differences in calculated error magnitude between species were less than typical scales of movement and had limited effect on movement model performance. Therefore, broad-scale interpretation of Argos tracking data will likely be unaffected, although fine-scale interpretation should be made with more caution for deep-diving species inhabiting warm regions.

Archaeologists have long subjected Clovis megafauna kill/scavenge sites to the highest level of scrutiny. In 1987, a Columbian mammoth (Mammuthus columbi) was found in spatial association with a small artifact assemblage in Converse County, Wyoming. However, due to the small tool assemblage, limited nature of the excavations, and questions about the security of the association between the artifacts and mammoth remains, the site was never included in summaries of human-killed/scavenged megafauna in North America. Here we present the results of four field seasons of new excavations at the La Prele Mammoth site that confirm the presence of an associated cultural occupation based on geologic context, artifact attributes, spatial distributions, protein residue analysis, and lithic microwear analysis. This new work identified a more extensive cultural occupation including the presence of multiple discrete artifact clusters in close proximity to the mammoth bone bed. This study confirms the presence of a second Clovis mammoth kill/scavenge site in Wyoming and shows the value in revisiting proposed terminal Pleistocene kill/scavenge sites.

Lions are one of the world’s most iconic megafauna, yet little is known about their temporal and spatial demographic history and population differentiation. We analyzed a genomic dataset of 20 specimens: two ca. 30,000-y-old cave lions (Panthera leo spelaea), 12 historic lions (Panthera leo leo/Panthera leo melanochaita) that lived between the 15th and 20th centuries outside the current geographic distribution of lions, and 6 present-day lions from Africa and India. We found that cave and modern lions shared an ancestor ca. 500,000 y ago and that the 2 lineages likely did not hybridize following their divergence. Within modern lions, we found 2 main lineages that diverged ca. 70,000 y ago, with clear evidence of subsequent gene flow. Our data also reveal a nearly complete absence of genetic diversity within Indian lions, probably due to well-documented extremely low effective population sizes in the recent past. Our results contribute toward the understanding of the evolutionary history of lions and complement conservation efforts to protect the diversity of this vulnerable species., S.J.O, was supported, in part, by St. Petersburg State University (Genome Russia Grant no. 1.52.1647.2016). T.M.-B. is supported by funding from BFU2017-86471-P (MINECO/FEDER, UE), Howard Hughes International Early Career, Obra Social “La Caixa” and Secretaria d’Universitats i Recerca and Centres de Recerca de Catalunya (CERCA) Programme del Departament d’Economia i Coneixement de la Generalitat de Catalunya (GRC 2017 SGR 880). We also acknowledge European Research Council (ERC) Consolidator Award 681396-Extinction Genomics to M.T.P.G. and Marie-Sklodowska Curie Fellowship 298820 “SIMBA” to R.B. for their generous funding.

Among the several fossils of South American tayassuids, it is remarkable the presence of a well-preserved skull from southern Brazil (Chui Creek, Santa Vitoria do Palmar, Santa Vitoria Formation). ...

One major challenge in the study of late-Quaternary extinctions (LQEs) is providing better estimates of past megafauna abundance. To show how megaherbivore population size varied before and after the last extinctions in interior Alaska, we use both a database of radiocarbon-dated bone remains (spanning 25–0 ka) and spores of the obligate dung fungus,Sporormiella,recovered from radiocarbon-dated lake-sediment cores (spanning 17–0 ka). Bone fossils show that the last stage of LQEs in the region occurred at about 13 ka ago, but the number of megaherbivore bones remains high into the Holocene.Sporormiellaabundance also remains high into the Holocene and does not decrease with major vegetation changes recorded by arboreal pollen percentages. At two sites, the interpretation ofSporormiellawas enhanced by additional dung fungal spore types (e.g.,Sordaria). In contrast to many sites where the last stage of LQEs is marked by a sharp decline inSporormiellaabundance, in interior Alaska our results indicate the continuance of megaherbivore abundance, albeit with a major taxonomic turnover (includingMammuthusandEquusextinction) from predominantly grazing to browsing dietary guilds. This new and robust evidence implies that regional LQEs were not systematically associated with crashes of overall megaherbivore abundance.

Theory predicts that trophic specialization (i.e. low dietary diversity) should make consumer populations sensitive to environmental disturbances. Yet diagnosing specialization is complicated both by the difficulty of precisely quantifying diet composition and by definitional ambiguity: what makes a diet 'diverse'? We sought to characterize the relationship between taxonomic dietary diversity (TDD) and phylogenetic dietary diversity (PDD) in a species-rich community of large mammalian herbivores in a semi-arid East African savanna. We hypothesized that TDD and PDD would be positively correlated within and among species, because taxonomically diverse diets are likely to include plants from many lineages. By using DNA metabarcoding to analyse 1,281 faecal samples collected across multiple seasons, we compiled high-resolution diet profiles for 25 sympatric large-herbivore species. For each of these populations, we calculated TDD and PDD with reference to a DNA reference library for local plants. Contrary to our hypothesis, measures of TDD and PDD were either uncorrelated or negatively correlated with each other. Thus, these metrics reflect distinct dimensions of dietary specialization both within and among species. In general, grazers and ruminants exhibited greater TDD, but lower PDD, than did browsers and non-ruminants. We found significant seasonal variation in TDD and/or PDD for all but four species (Grevy's zebra, buffalo, elephant, Grant's gazelle); however, the relationship between TDD and PDD was consistent across seasons for all but one of the 12 best-sampled species (plains zebra). Our results show that taxonomic generalists can be phylogenetic specialists, and vice versa. These two dimensions of dietary diversity suggest contrasting implications for efforts to predict how consumers will respond to climate change and other environmental perturbations. For example, populations with low TDD may be sensitive to phylogenetically 'random' losses of food species, whereas populations with low PDD may be comparatively more sensitive to environmental changes that disadvantage entire plant lineages-and populations with low dietary diversity in both taxonomic and phylogenetic dimensions may be most vulnerable of all.

This paper brings together a wide range of concepts from climate change predictions, palaeoecology, wildlife ecology and sustainable livelihoods in order to prioritise adaptive management measures that are necessary for the conservation of the African megafauna. Climate change predictions emphasise the severe aridity that will surge into southern Africa later this century and must be contrasted with the relatively wetter conditions in eastern Africa. The evolution of African mammals and their adaptive responses to past episodes of climate change is explained by reference to range shifts and movements along Balinsky’s (1962) ‘drought corridor’ that extends from SW Africa northeastwards to Somalia and then westwards across the Saharan-Sahelian zone. The drought corridor today could potentially extend from Kenya southwestward through to Botswana/South Africa and Namibia, via connectivity corridors linking existing wildlife areas, forming the Kalahari-Rift Valley Transfrontier Conservation Landscape (KALARIVA TFCL). The most promising route along the drought corridor links the Chobe – Linyanti – Kwando river systems of Botswana/Namibia with Luangwa Valley in Northern Zambia, along the Zambezi River via Lake Kariba (Matsudonna and Mana Pools) in Zimbabwe. Malawi poses an absolute barrier to such connectivity and by the turn of this Century runs the risk of confining the area to the south almost entirely to the SW arid adapted fauna and that to the north to water dependent ungulates such as elephants, buffalo and zebra. The key movement corridors are identified in a bid to extend the spatial and temporal scale of conservation planning in order to adapt effectively to climate change. The importance of ‘co-existence’ between wildlife and people is emphasised together with the need for local communities to benefit from sharing the KALARIVA TFCL with African wildlife, via new models of conservation financing and management that reward rural African communities for being the true custodians of the African megafauna.

Despite at least 20,000 years of coexistence – and the ubiquity of bone technology across the Australian continent – direct evidence for the use of megafaunal materials (skin, bone, teeth, etc.) remains as elusive as evidence for these creatures having been hunted. Amongst the slim evidence for human–megafauna interaction currently available, one of the most often cited cases is the “engraved” incisor from the giant wombat-like Diprotodon optatum recovered from Spring Creek located in Eastern Maar country in south-eastern Australia. Despite comments in the literature that the marks observed on this tooth are unlikely to have been made by lithic tools (as originally proposed), this item has never been re-analysed in order to resolve the question: Which actor made these marks? Here, the results of a new analysis of this specimen are presented. Through microscopic examination of each mark alongside zooarchaeological and ecological data, it is demonstrated that the incisions were indeed not made by human hands, but instead by a small (2–5 kg) mammal, most likely a scavenging spotted-tailed quoll (Dasyurus maculatus).

Supporting information: Figure S1. A three‐dimensional model of the bathymetry in Tristan da Cunha EEZ highlighting the seamounts. Figure S2. Plot of the raw tracking data of all 10 species considered in our analysis of marine hotspots within the Tristan da Cunha EEZ (indicated by the solid black line). Table S1. Plot of the raw tracking data of all 10 species considered in our analysis of marine hotspots within the Tristan da Cunha EEZ (indicated by the solid black line). Table S2. Phenology of the seabird species breeding in the Territory of Tristan da Cunha. Tristan Table S3. Proportion of the time‐at‐sea spent by different species inside and outside the Tristan EEZ based on tracking data of pelagic megafauna activity in the Tristan da Cunha Exclusive Economic Zone. Figure S3. The tracks of three Blue Shark (Prionace glauca) tagged during the National Geographic’s Pristine Seas expedition to Tristan da Cunha (January to February 2017), using MiniPAT tags (Wildlife Computers).

Identification of important habitats of charismatic marine megafauna is essential to enhance our conservation capacity. Still, for species like sea turtles that have a long-life span, a complex life history and a highly migratory nature, spatially delineating important marine areas is not a simple task. Even in the case that such areas could be identified, our ability to draw effective measures and propose conservation prioritization schemes faces additional challenges, due to the dynamic climate-driven redistribution of habitats. Here, we compile a database on foraging locations of loggerhead sea turtles across the Mediterranean Sea and use climatic niche models to predict the distribution of foraging grounds for juvenile and adult life stages. We explore potential shifts due to future changes in ocean temperature and identify sites, considered as important for both life-cycle stages, that will persist under climate change. We found extensive areas which could host foraging sites for juvenile loggerheads, distributed at the central and western Mediterranean, while adults’ foraging grounds had a more sparse and patchy distribution, mostly at the central and eastern part of the basin. Under future changes, expansions prevail over contractions, but projected redistribution of foraging space for both life stages will probably lead to remarkable losses of climatic suitability at certain sites. Important areas, hosted primarily at the neritic zone, will extend their coverage in the future. Our analyses add a missing dimension to conservation efforts, related to the basin-wide distribution of important areas, offering novel insights towards incorporating climate change into conservation planning.

During RV MS Merian expedition MSM75, an international, multidisciplinary team explored the Reykjanes Ridge from June to August 2018. The first area of study, Steinahóll (150–350 m depth), was chosen based on previous seismic data indicating hydrothermal activity. The sampling strategy included ship- and AUV-mounted multibeam surveys, Remotely Operated Vehicle (ROV), Epibenthic Sledge (EBS), and van Veen grab (vV) deployments. Upon returning to Steinahóll during the final days of MSM75, hydrothermal vent sites were discovered using the ROV Phoca (Kiel, GEOMAR). Here we describe and name three new, distinct hydrothermal vent site vulnerable marine ecosystems (VMEs); Hafgufa, Stökkull, Lyngbakr. The hydrothermal vent sites consisted of multiple anhydrite chimneys with large quantities of bacterial mats visible. The largest of the three sites (Hafgufa) was mapped, and reconstructed in 3D. In total 23,310 individual biological specimens were sampled comprising 41 higher taxa. Unique fauna located in the hydrothermally venting areas included two putative new species of harpacticoid copepod (Tisbe sp. nov. and Amphiascus sp. nov.), as well as the sponge Lycopodina cupressiformis (Carter, 1874). Capitellidae Grube, 1862 and Dorvilleidae Chamberlin, 1919 families dominated hydrothermally influenced samples for polychaetes. Around the hydrothermally influenced sites we observed a notable lack of megafauna, with only a few species being present. While we observed hydrothermal associations, the overall species composition is very similar to that seen at other shallow water vent sites in the north of Iceland, such as the Mohns Ridge vent fields, particularly with peracarid crustaceans. We therefore conclude the community overall reflects the usual “background” fauna of Iceland rather than consisting of “vent endemic” communities as is observed in deeper vent systems, with a few opportunistic species capable of utilizing this specialist environment.

Guava (Psidium guajava L., Myrtaceae) is a Neotropical fruit that is widely consumed around the world. However, its evolutionary history and domestication process are unknown. Here we examine available ecological, taxonomic, genetic, archeological, and historical evidence about guava. Guava needs full sunlight, warm temperatures, and well-distributed rainfall throughout the year to grow, but tolerates drought. Zoochory and anthropochory are the main forms of dispersal. Guava’s phylogenetic relationships with other species of the genus Psidium are unclear. A group of six species that share several morphological characteristics are tentatively accepted as the Psidium guajava complex. DNA analyses are limited to the characterization of crop genetic diversity within localities and do not account for possible evolutionary and domestication scenarios. A significant amount of archeological information exists, with a greater number and older records in South America than in Mesoamerica, where there are also numerous historical records. From this information, we propose that: (1) the guava ancestor may have originated during the Middle or Late Miocene, and the savannas and semi-deciduous forests of South America formed during the Late Pleistocene would have been the most appropriate ecosystems for its growth, (2) the megafauna were important dispersers for guava, (3) dispersal by humans during the Holocene expanded guava’s geographic range, including to the southwestern Amazonian lowlands, (4) where its domestication may have started, and (5) with the European conquest of the Neotropics, accompanied by their domestic animals, new contact routes between previously remote guava populations were established. These proposals could direct future research on the evolutionary and domestication process of guava.

Marine plastic abundance has increased over the past 60 years and microplastics (

Pathways to extinction start long before the death of the last individual. However, causes of early stage population declines and the susceptibility of small residual populations to extirpation are typically studied in isolation. Using validated process-explicit models, we disentangle the ecological mechanisms and threats that were integral in the initial decline and later extinction of the woolly mammoth. We show that reconciling ancient DNA data on woolly mammoth population decline with fossil evidence of location and timing of extinction requires process-explicit models with specific demographic and niche constraints, and a constrained synergy of climatic change and human impacts. Validated models needed humans to hasten climate-driven population declines by many millennia, and to allow woolly mammoths to persist in mainland Arctic refugia until the mid-Holocene. Our results show that the role of humans in the extinction dynamics of woolly mammoth began well before the Holocene, exerting lasting effects on the spatial pattern and timing of its range-wide extinction.

In May–June 2021, wild Asian elephants, Elephas maximus, in Southwest China made global headlines when a herd of 15 trekked north toward the 8-million-person city of Kunming, while another herd of similar size moved south into a popular botanical garden. Both herds used to live in the Mengyang section of the Xishuangbanna National Nature Reserve (hereafter Mengyang; 22.2oN, 100.9oE), from which both departed in March 2020, moving into areas with no living memory of elephants. For several weeks, the “wandering elephants” drew unprecedented public attention on Asian elephant conservation, while mobilizing an extraordinary amount of resources (800 officers and 270 vehicles at the peak of the monitoring and management operation; Fei Chen pers. obs.). Here, we address the causes and conservation implications of this unusual behavior.

A 42,000-year record of coprophilous fungal (Sporormiella, Podospora, Cercophora), fossil pollen and charcoal data assessed megafaunal use of woodland versus grassland settings in Central American landscapes by Pleistocene megafauna. The sedimentary record from Lake Petén-Itzá showed that vegetation growing around the lake shifted between scrub grasslands, Pinus-dominated woodlands, Quercus-dominated woodlands, and tropical seasonal forest. A series of regression analyses and probabilistic models revealed that vegetation assemblages and temperature influenced the abundance of coprophilous fungus, a proxy for megafaunal abundance. We found that megafaunal populations were almost continuously present around Petén-Itzá during the Pleistocene, and that the peak abundances appear to have been associated with cool, moist Quercus-rich parklands. In contrast, the lowest inputs of coprophilous fungi occurred during cold, dry events when scrub grasslands expanded. The dry grasslands may have been nutrient-limited, offering poor quality grazing for megafauna. The decline of the Pleistocene megafauna at Petén-Itzá was a multi-stage event, with a series of population collapses prior to an inferred local extirpation c. 13,600 years ago.

Subsea infrastructure supporting the oil and gas and renewable energy industries can attract commercially important fish species as well as megafauna including sea lions, turtles, sharks, manta rays and whales. Potential impacts of this attraction, whether positive and negative, on migratory marine megafauna remain unknown. We deployed acoustic telemetry equipment around subsea infrastructure in a pilot study that aimed to assess its effectiveness in detecting visiting tagged marine animals and to understand how megafauna species may utilise these structures. We deployed acoustic receivers around four oil and gas platforms and on two remotely operated vehicles (ROVs) undertaking pipeline inspections on Australia’s North West Shelf. The ROV-attached receivers failed to detect any animals. However, two whale sharks (Rhincodon typus) previously tagged in the World Heritage Ningaloo Reef Marine Park were detected at two different platforms, North Rankin A and Pluto, located up to 340 km north of the initial tagging locations. The whale shark at North Rankin A visited the platform infrequently over ~6 weeks with a total of 15 detections. In contrast, the whale shark at Pluto platform was detected each day of the 24-day deployment, with a total of 4894 detections. Detections at Pluto platform were highest during the day, with peaks at dusk and dawn. Our lack of detections from the ROV pipeline surveys and other platforms probably reflect the small number of tagged animals in the region and a poor understanding of the range of the receivers in these environments. However, our pilot study indicates that acoustic telemetry around platforms may be an effective method for understanding how marine megafauna utilise these structures. We recommend collaborating with industry to undertake receiver range testing to better understand the effectiveness of the method. We further recommend that studies such as these should occur in parallel with intensive tagging programs at sites like Ningaloo Reef and around the structures themselves to maximise the probability of detections and improve our understanding of how marine megafauna use these structures.

The Dugong dugon (dugong) and Chelonia mydas (green sea turtle) are economically and culturally significant marine mega-herbivores whose populations are declining globally. Capture of these animals for study is challenging and stressful for the animals. Ecological questions can be answered using faeces, which can be collected floating on the water’s surface. However, green turtle and dugong faeces are visually indistinguishable. Specific PCR primer pairs were developed based on the mitochondrial control region of each species. We were able to determine species of origin using DNA extracted, amplified and sequenced from faeces. This provides a valuable tool for non-invasive taxonomic identification to assist the conservation of these vulnerable and endangered species.

Two alternative stimulation techniques to reduce mortality in benthic megafauna were tested relative to standard tickler chain beam trawling: longitudinal electrodes (pulse trawl) and longitudinal chains. Longitudinal chains caused higher mortality than pulse trawling in 3 species. Standard trawling gave higher mortality in Echinocardium cordatum than pulse trawling. Between longitudinal chain and standard trawling were no significant differences. This trend in decreasing mortality from longitudinal, to standard and then pulse trawling was confirmed by a similar decline in: i) numbers of significant species mortalities per trawl type, ii) average mortalities, i.e. longitudinal chain caused 41% more mortality than standard trawling and pulse trawling 43% less, iii) pre- and post-trawling community dissimilarities. A significant majority of species showed higher mortalities after longitudinal than after standard trawling and, conversely, lower mortalities after pulse trawling. Trawls with longitudinal chains instead of cross tickler chains increase megafaunal impact. On the contrary, pulse trawling can reduce the impact, although average mortality remains substantial (25%) even in impoverished benthic test assemblages in the southern North Sea. Power, generally was low and reference areas, free of (pulse) trawling, and inhabited by more vulnerable taxa will facilitate higher powered studies on the impact of standard and alternative trawling techniques.

Xenophyophores, giant deep-sea agglutinated foraminifera, dominate the benthic megafauna in the eastern equatorial Pacific Clarion-Clipperton Zone. This abyssal (>4000 m depth) region hosts major deposits of polymetallic nodules targeted for future seabed mining, an activity that would destroy these highly diverse and delicate protists, particularly those living on the nodules themselves. Since the cell occupies only a small proportion of their test volume, xenophyophores may make a fairly modest contribution to benthic biomass and carbon cycling. Nevertheless, xenophyophore tests can passively enhance particle deposition, concentrate food, and provide habitat structure utilized by diverse organisms. Their destruction could therefore influence the recovery of benthic communities. Species requiring nodule substrates will likely not recover, since nodules take millions of years to form. However, xenophyophores can grow quickly and colonize extensive volcanic ash deposits within years, suggesting that sediment-dwelling species could be among the first large immobile organisms to reappear in mining-impacted areas.

Dicynodonts, a lineage of non-mammalian therapsids, who's derived taxa evolved edentulous beaked jaws sporting a pair of caniniform tusks, dominated the herbivorous terrestrial vertebrate fauna for much of the Permian and Triassic periods. Long assumed to have met their demise during the end-Triassic extinction event, the discovery of a fragmentary possible dicynodont in Cretaceous rocks in Queensland Australia, potentially extended the longevity of the lineage by nearly 100 million years. This study reassesses the geological, anatomical and historical aspects of this specimen through museum archival research, detrital zircon geochronology, trace element analysis and x-ray synchrotron microtomography, and present new knowledge regarding its temporal, geographical and biological origins, supporting a late Cenozoic (Pliocene-Pleistocene) mammalian megafaunal affinity for the specimen, resulting in a lack of evidence for post-Triassic survival of dicynodonts.

We performed a macroscopic and radiological inspection in a set of bones belonging to the fossil mammal assemblage of Zabele Paleontological Site (Late Pleistocene-Northgrippian), in northeastern B...

Bison (Bison bison) are one of the few terrestrial megafauna to survive the transition into the Holocene and provide a unique opportunity to study a species on a broad spatiotemporal scale. Today, bison are primarily managed in small and isolated herds with little known about their ancestral ecology. We studied the carbon and nitrogen isotopes of Northern Great Plains bison from the terminal Pleistocene and throughout the Holocene to gain insight into their paleoecology. This time span is contemporary with the first population bottleneck experienced by bison at the end of the Pleistocene and includes the second bottleneck which occurred in the late 19th century. Results were compared with modern bison herd isotopic values from Theodore Roosevelt National Park (TRNP). Patterns of isotopic variation found in bison over time indicate significant (δ13C p = 0.0008, δ15N p = 0.002) differences in diet composition and correlate with climate throughout the Holocene. Isotopic relationships described here reveal the plasticity of ancient bison in unrestricted rangelands during periods of climatic fluctuations. Managers at TRNP and elsewhere should pursue opportunities to expand bison range to maximize forage opportunities for the species in the face of future environmental change.

In 2008 a rich accumulation of vertebrate bones and teeth was discovered in a small tributary drainage to Big Cypress Creek near the town of Hockley in Harris County, Texas. The fossils were recovered from sandy sediments of fluvial origin, interspersed with contemporaneous spring boil deposits, attributed to the Deweyville Formation and the recovered remains consist entirely of disarticulated and dissociated skeletal elements and teeth. Distinct stratigraphic horizons are limited in extent in the fossiliferous sections along the drainage, and the fossils are generally concentrated in close association with gravel lag deposits. Two radiocarbon dates on wood suggest that the fauna may have accumulated about 24,000 years ago but presence of spring deposits, association with lag deposits, and the aerial extent (approximately 125 m of exposed section along the length of the tributary) could indicate significant time averaging during the Rancholabrean (Bison occurs in the fauna). The unique faunal character of the site is emphasized by a single tooth of Mixotoxodon, a notoungulate mammal, that provides the first evidence of this taxon from the United States. The fauna is dominantly composed of herbivorous megafauna with two proboscideans (Mammuthus and Cuvieronius). Mammut americanum has not yet been found in the fauna. Isotopic analyses of the proboscideans and some of the other megafauna suggest that an open environment with scattered woodland habitat existed in southeastern Texas at the end of the last glacial period.

Herbivory is an important ecological process than has influenced the evolution of grassland-savannah systems. The evolutionary history of herbivory largely determines how resilient plant communities are to herbivory, with communities evolving with a long history generally possessing plant adaptations that make them able to cope with such disturbance. Thus, the evolutionary history of herbivory can serve as an indicator of a system’s resilience to modern grazing. Determining this history, however, is problematic because quantitative measures of herbivory and knowledge of plant origin are needed over appropriate evolutionary time frames. Paleoecology offers a useful framework for assessing this evolutionary history of plant-herbivore interactions. The Patagonian steppe is a phytogeographic province of South America whose evolutionary history of herbivory has been debated. Past discussions have focused completely on the abundance of its sole large ungulate herbivore—the guanaco (Lama guanicoe Muller 1776)—since European colonization of the continent. Here we use a paleoecological approach to reconstruct the evolutionary history of herbivory and plant evolution in the Patagonian steppe over a much broader, geologic time frame (Cenozoic) to shed light on the matter. We examine the role of past climate, ancient megafauna, and guanaco in shaping the vegetation and briefly discuss how present land use may be misaligned with the steppe’s evolutionary history of herbivory.

Fisheries bycatch is one of main conservation problems for many threatened seabirds. Currently, it is unknown whether existing best practices to mitigate seabird bycatch in pelagic longline fisheries influence the capture of other vulnerable taxa. We assessed the effect of two seabird mitigation measures for pelagic longline fisheries on 13 threatened, protected and/or bycaught species, including elasmobranchs, teleosts, sea turtles and fur seals. Analyses were from two experimental studies in Uruguay assessing the effect of a bird scaring line (BSL) and branch lines with weights close to the hooks (weighted branch lines) on these taxa. One hundred longline sets with randomized use of a BSL were deployed. In turn, 224 paired longline sections, with control branch lines versus weighted branch lines, were deployed. BSL use did not increase the capture of any of the species addressed. No detectable differences in capture rate were recorded in our branch line weighting study. However, the effect of branch line weighting in the capture of Porbeagle shark (Lamna nasus) remains unclear and requires further research. Our study suggests that effective measures to reduce seabird bycatch in pelagic longline have no negative connotations for other vulnerable species. Caution should be exercised when interpreting our results as analyses were underpowered to detect small and subtle differences in the catch rates. We strongly encourage researchers to conduct similar studies to elucidate potential regional and across fisheries differences in the effect of seabird mitigation measures in other vulnerable taxa, as well as the effect that mitigation measures for other taxa may have on seabirds.