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Translocated populations must adapt to their new environment to survive. A key aspect of survival for insects is the maintenance of water balance. It is thought that insects can adapt to dry environments by adjusting their cuticular hydrocarbon (CHC) profile to reduce water loss, though there is limited empirical support for this, and studies generally focus on other roles of CHCs, such as chemical communication. We tested for phenotypic adaptation in introduced populations of the Mediterranean dung beetle Onthophagus taurus, which have become established along a climatic gradient from dry northern to wet southern locations in southwestern Australia. We compared CHC profiles and desiccation resistance between northern and southern populations of the species. To quantify desiccation resistance, we measured both the rate of weight loss and time until death in beetles incubated at 35 °C. We tested for associations between these measures of desiccation resistance and CHC profiles, which were obtained through gas chromatography mass spectrometry. The abundance of CHCs was positively associated with desiccation resistance, and individuals that underwent the desiccation treatment produced a greater quantity of several CHC compounds indicating their ability to plastically adjust their CHC profile in response to desiccation stress. However, northern populations did not produce more CHCs than southern populations, and southern populations were better able to tolerate desiccation. Our results suggest that CHCs are an important component of desiccation resistance in O. taurus. However, the lack of evidence for local adaptation to the drier northern climate suggests there may be constraints to increasing desiccation resistance, and demonstrates the importance of considering local environmental conditions before translocating populations to new locations. [ABSTRACT FROM AUTHOR]

Coptotermes formosanus, known in its native China as the 'House White Ant', was introduced to the southeast USA likely in the 1950s, where it is known as the Formosan subterranean termite. In the USA it is best known as a pest of buildings in urban areas, however C. formosanus also attacks live trees along streets and in urban parks, suggesting it may be able to invade forests in the USA. A survey of 113 forest patches around Charleston South Carolina and New Orleans Louisiana, where C. formosanus was first recorded, found that 37% and 52%, respectively, were infested. Resistograph measurement of internal hollows in tree trunks in forest patches infested with C. formosanus found infested sites contained more and larger hollows compared with non-infested sites. Compared with forest patches free of C. formosanus, infested patches had 32% more trees with hollows in Charleston, and 115% more in New Orleans. Similarly, compared with patches free of C. formosanus, hollows were 2–3 times larger in infested patches in Charleston, and 2–6 times larger in New Orleans. Quercus (oak) and Acer (maple) were the most damaged trees in Charleston, whereas Carya (bitternut hickory), Taxodium (bald cypress), Nyssa (blackgum) and Liquidamber (sweetgum) were the most damaged in New Orleans. As termite damaged trees are more likely to die, these differing damage levels between tree species suggests that C. formosanus may alter community structure in US forests. [ABSTRACT FROM AUTHOR]

Most people consider cockroaches to be quintessential urban pests, even though very few of the 5000 cockroach species live in urban areas. The German cockroach is the most widespread and common cockroach in urban areas, however how this invasive species has spread globally is poorly understood. We reviewed the published and grey literatures, and museum data, to document the spread of the German cockroach, and how it may have interacted with other urban cockroach species. We found that the German cockroach likely originated from South Asia, was introduced into Europe no later than the 18th century, from where it invaded worldwide. The spread of the German cockroach was facilitated by the improvement of transportation technologies, especially from colonial trading, and indoor heating in cooler climates. Studies of population genetics have found that once introduced into a new location, the German cockroach spread rapidly through local expansion, and this could be within single (large, multiple-story) buildings. This local expansion resulted in displacement of other urban cockroach species, likely due to their small size requiring fewer resources, shorter generation times and so faster evolution, especially for pesticide resistance. These findings may help to identify new pest management methods. Future research could use genetic tools at larger scales to map distribution routes across the globe and interaction with pesticides and the evolution of resistance. [ABSTRACT FROM AUTHOR]

The use of genome-wide genetic markers is an emerging approach for informing evidence-based management decisions for highly threatened species. Pangolins are the most heavily trafficked mammals across illegal wildlife trade globally, but critically endangered Sunda pangolins (Manis javanica) have not been widely studied in insular Southeast Asia. We used > 12,000 single nucleotide polymorphic markers (SNPs) to assign pangolin seizures from illegal trade of unknown origin to possible geographic sources via genetic clustering with pangolins of known origin. Our SNPs reveal three previously unrecognized genetic lineages of Sunda pangolins, possibly from Borneo, Java and Singapore/Sumatra. The seizure assignments suggest the majority of pangolins were traded from Borneo to Java. Using mitochondrial markers did not provide the same resolution of pangolin lineages, and to explore if admixture might explain these differences, we applied sophisticated tests of introgression using > 2000 SNPs to investigate secondary gene flow between each of the three Sunda pangolin lineages. It is possible the admixture which we discovered is due to human-mediated movements of pangolins. Our findings impact a range of conservation actions, including tracing patterns of trade, repatriation of rescue animals, and conservation breeding. In order to conserve genetic diversity, we suggest that, pending further research, each pangolin lineage should as a precaution be protected and managed as an evolutionarily distinct conservation unit. [ABSTRACT FROM AUTHOR]

Urban ecosystems are characterized by 'urban exploiters': species that thrive in the modified environment of cities. Few insects have been categorized as such, in part because they are usually considered as pests first, in part because many studies do not identify to species, and in part because many insects can survive in small vegetated areas within the urban matrix. Some termites may be prime examples of urban exploiters; Coptotermes species are rare in natural forests, but are abundant and major pests in urban areas. We investigated the genetic structure of the South East Asian species Coptotermes gestroi in the urban nation of Singapore. There was a panmictic population across the city, yet all 29 colonies were genetically distinct, and many had expanded from recent bottlenecks. There were no significant differences between colonies in vegetated areas (forests and parks), and those in urban habitats. The genetic pattern is similar to some other urban exploiter species in comparable environments, thus confirming C. gestroi is a native species that has become an urban exploiter, the first termite to be considered as such. [ABSTRACT FROM AUTHOR]

Baiting is considered to be a relatively environmentally benign termite control method; however, all commercial baiting systems are designed for species in the Rhinotermitidae and are used primarily in temperate countries. Fungus-growing termites in the Macrotermitidae can be important pests in tropical countries; they can be difficult to control using all available methods, and there are no baiting systems designed for them. We tested bait station size, an important component of bait station design, against two Macrotermes species in Singapore. Macrotermes gilvus recruited to small stations (0.35 L) very poorly and medium stations (3.6 L) poorly (both similar in size to various commercial stations), but they recruited to large stations (11.5 L) well. Macrotermes carbonarius followed a similar pattern but recruited to fewer stations overall. In the occupied stations, M. gilvus ate the bait wood, sometimes creating a fungus garden inside the stations, and brought little soil into the stations. In comparison, M. carbonarius ate no wood at all, but filled stations with soil. There was significantly less leaf litter around M. carbonarius mounds compared with M. gilvus mounds, although there were no obvious differences in habitat, which suggested that M. carbonarius eats leaf litter only and is not a pest species. Our study shows that stations much larger than current commercial options may provide a useful means for controlling pest wood-eating, fungus-growing termites in tropical countries. [ABSTRACT FROM AUTHOR]

The German cockroach is one of the world's most widespread invasive species. From uncertain origins, it appears in historical records in Europe over 300 years ago, with the first records in China date from 100 years ago. Since the 1990s, the German cockroach has dominated indoor environments across China. A genetic analysis of 599 individuals from nine cities across China found two genetic clusters; one dominant in the North and the other dominant the in South of the country. Weak but significantly positive isolation by distance was observed for the entire country; however, when broken into different geographical scales, the significantly positive correlation can be only observed in between cities or city to suburb range (10-221 km). Two factors may have contributed to the spread of the German cockroach in China, which correspond to these two clusters: central heating systems in the north built during the 1960s, and air-conditioning systems in the south built during in the 1990s. The spread of modern, long distance transport systems, such as railways, may have contributed to the lack of geographic patterns, yet it is likely that other factors have been important in determining patterns. [ABSTRACT FROM AUTHOR]

Self-control tasks used with nonhuman animals typically involve the choice between an immediate option and a delayed, but more preferred option. However, in many self-control scenarios, not only does the more impulsive option come sooner in time, it is often more concrete than the delayed option. For example, studies have presented children with the option of eating a visible marshmallow immediately, or foregoing it for a better reward that can only be seen later. Thus, the immediately available option is visible and concrete, whereas the delayed option is not visible and more abstract. We tested eight capuchin monkeys to better understand this potential effect by manipulating the visibility of the response options and the visibility of the baiting itself. Monkeys observed two food items (20 or 5 g pieces of banana) each being placed either on top of or inside of one of the two opaque containers attached to a revolving tray apparatus, either in full view of monkeys or occluded by a barrier. Trials ended when monkeys removed a reward from the rotating tray. To demonstrate self-control, monkeys should have allowed the smaller piece of food to pass if the larger piece was forthcoming. Overall, monkeys were successful on the task, allowing a smaller, visible piece of banana to pass from reach in order to access the larger, nonvisible banana piece. This was true even when the entire baiting process took place out of sight of the monkeys. This finding suggests that capuchin monkeys succeed on self-control tasks even when the delayed option is also more abstract than the immediate one-a situation likely faced by primates in everyday life. [ABSTRACT FROM AUTHOR]

The asymmetric dominance effect (or decoy effect) is a form of context-dependent choice bias in which the probability of choosing one of two options is impacted by the introduction of a third option, also known as the decoy. Decoy effects are documented widely within the human consumer choice literature, and even extend to preference testing within nonhuman animals. Here, we extended this line of research to a perceptual discrimination task with rhesus monkeys to determine whether decoy stimuli would impact size judgments of rectangular stimuli. In a computerized task, monkeys attempted to choose the larger of two rectangles that varied in size and orientation (horizontally or vertically oriented). In probe trials, a third stimulus (the decoy) was presented that was smaller than the other two rectangles but matched the orientation of one of them. On half of the probe trials, the presented decoy matched the orientation of the larger stimulus, and on the other half, the decoy matched the orientation of the smaller stimulus. Monkeys rarely selected the decoy stimulus. However, their performance (selection of the largest rectangle) increased relative to the baseline trials (with only two choices) when the decoy was congruent in its orientation with the largest rectangle, but decreased relative to baseline when the decoy was incongruent with the largest rectangle. Thus, a decoy stimulus impacted monkeys' perceptual choice behavior even when it was not a viable choice option itself. These results are explained with regard to comparative evaluation mechanisms. [ABSTRACT FROM AUTHOR]

Eusocial insects such as bees, ants and termites communicate multi-modally using chemical, visual, tactile and vibrational cues. While much work has been done on chemical and visual communications, the tactile and vibrational communication channel is somewhat neglected. Recent research indicates that structural vibrations caused by ants can be used to identify their activity level. However, these structural vibrations are caused by the response of the substrate excited by ants walking. The objective of this study is to determine the footprint of ants walking by separating the response of the substrate from the walking signal. The vibration of the substrate (in this case, a wooden veneer) caused by ants walking is measured by a laser vibrometer in an experimental setup isolated from environmental vibrations. By filtering the recorded vibration signal using a technique based on the dynamics in phase space followed by deconvolution from the response of the veneer using Tikhonov regularisation, the ant's walking signal is extracted and its nature determined. [ABSTRACT FROM AUTHOR]

Both empirical and anecdotal evidence supports the idea that choice is preferred by humans. Previous research has demonstrated that this preference extends to nonhuman animals, but it remains largely unknown whether animals will actively seek out or prefer opportunities to choose. Here we explored the issue of whether capuchin and rhesus monkeys choose to choose. We used a modified version of the SELECT task-a computer program in which monkeys can choose the order of completion of various psychomotor and cognitive tasks. In the present experiments, each trial began with a choice between two icons, one of which allowed the monkey to select the order of task completion, and the other of which led to the assignment of a task order by the computer. In either case, subjects still had to complete the same number of tasks and the same number of task trials. The tasks were relatively easy, and the monkeys responded correctly on most trials. Thus, global reinforcement rates were approximately equated across conditions. The only difference was whether the monkey chose the task order or it was assigned, thus isolating the act of choosing. Given sufficient experience with the task icons, all monkeys showed a significant preference for choice when the alternative was a randomly assigned order of tasks. To a lesser extent, some of the monkeys maintained a preference for choice over a preferred, but computer-assigned, task order that was yoked to their own previous choice selection. The results indicated that monkeys prefer to choose when all other aspects of the task are equated. [ABSTRACT FROM AUTHOR]

Self-control has been studied in nonhuman animals using a variety of tasks. The inter-temporal choice (ITC) task presents choices between smaller-sooner (SS) and larger-later (LL) options. Using food amounts as rewards, this presents two problems: (a) choices of the LL option could either reflect self-control or instead result from animals' difficulty with pointing to smaller amounts of food; (b) there is no way to verify whether the subjects would not revert their choice for the LL option, if given the opportunity to do so during the ensuing delay. To address these problems, we have recently introduced a new protocol, the hybrid delay task, which combines an initial ITC with a subsequent accumulation phase in which selection of the SS option leads to its immediate delivery, but choice of the LL option then leads to one-by-one presentation of those items that continues only as long as the subject does not eat any of the accumulated items. The choice of the LL option therefore only reflects self-control when the number of items obtained from LL choices during the accumulation phase is higher than what could be received in the SS option. Previous research with capuchin monkeys demonstrated that their apparent self-control responses in the ITC task may have overestimated their general self-control abilities, given their poor performance in the hybrid delay task. Here, chimpanzees instead demonstrated that their choices for the LL option in the ITC phase of the hybrid delay task were confirmed by their ability to sustain long delays during accumulation of LL rewards. [ABSTRACT FROM AUTHOR]

Prospective memory (PM) involves remembering to do something at a specific time in the future. Here, we investigate the beginnings of this ability in young children (3-year-olds; Homo sapiens) and chimpanzees ( Pan troglodytes) using an analogous task. Subjects were given a choice between two toys (children) or two food items (chimpanzees). The selected item was delivered immediately, whereas the unselected item was hidden in an opaque container. After completing an ongoing quantity discrimination task, subjects could request the hidden item by asking for it (children) or by pointing to the container and identifying the item on a symbol board (chimpanzees). Children and chimpanzees showed evidence of prospective-like memory in this task, as evidenced by successful retrieval of the item at the end of the task, sometimes spontaneously with no prompting from the experimenter. These findings contribute to our understanding of PM from an ontogenetic and comparative perspective. [ABSTRACT FROM AUTHOR]

There has been extensive research investigating self-control in humans and nonhuman animals, yet we know surprisingly little about how one's social environment influences self-control. The present study examined the self-control of chimpanzees in a task that required active engagement with conspecifics. The task consisted of transferring a token back and forth with a partner animal in order to accumulate food rewards, one item per token transfer. Self-control was required because at any point in the trial, either chimpanzee could obtain their accumulated rewards, but doing so discontinued the food accumulation and ended the trial for both individuals. Chimpanzees readily engaged the task and accumulated the majority of available rewards before ending each trial, and they did so across a number of conditions that varied the identity of the partner, the presence/absence of the experimenter, and the means by which they could obtain rewards. A second experiment examined chimpanzees' self-control when given the choice between immediately available food items and a potentially larger amount of rewards that could be obtained by engaging the token transfer task with a partner. Chimpanzees were flexible in their decision-making in this test, typically choosing the option representing the largest amount of food, even if it involved delayed accumulation of the rewards via the token transfer task. These results demonstrate that chimpanzees can exhibit self-control in situations involving social interactions, and they encourage further research into this important aspect of the self-control scenario. [ABSTRACT FROM AUTHOR]

Self-control is defined as foregoing an immediate reward to gain a larger delayed reward. Methods used to test self-control comparatively include inter-temporal choice tasks, delay of gratification tasks, and accumulation tasks. To date, capuchin monkeys have shown different levels of self-control across tasks. This study introduced a new task that could be used comparatively to measure self-control in an intuitive context that involved responses that required no explicit training. Capuchin monkeys ( Cebus apella) were given a choice between two food items that were presented on a mechanized, revolving tray that moved those foods sequentially toward the monkeys. A monkey could grab the first item or wait for the second, but was only allowed one item. Most monkeys in the study waited for a more highly preferred food item or a larger amount of the same food item when those came later, and they inhibited the prepotent response to grab food by not reaching out to take less-preferred foods or smaller amounts of food that passed directly in front of them first. These data confirm that the mechanisms necessary for self-control are present in capuchin monkeys and indicate that the methodology can be useful for broader comparative assessments of self-control. [ABSTRACT FROM AUTHOR]

When information is incomplete but a choice must be made, individuals sometimes can rely on past experiences to help them assess uncertain outcomes in terms of the probabilities of payoffs. Monkeys ( Cebus apella) and humans ( Homo sapiens) were presented with a test in which they first made quantity judgments between two clear options. Then they made choices in which only one option was visible, and they had to estimate the quantity for the other option. Both species were guided by the past outcomes, as they shifted from selecting the known option to selecting the unknown option at the point at which the known option went from being greater than the average rate of return to being less than the average rate of return. This comparability across species suggests that tallying ongoing average rates of return from repeated choices occurs spontaneously and likely serves an adaptive purpose when dealing with uncertainty in the environment. [ABSTRACT FROM AUTHOR]

ll highly cryptic drywood termites derive their food and water from a single piece of wood. Despite the fact that most species share the same life cycles, only a few have become invasive tramp species. Variation in production of replacement reproductives and food size choice were determined for nine species of the important drywood genus Cryptotermes in a test with two different sized wooden blocks. Four native, non-pest species produced one or two reproductives, gnawed short tunnels and chose large blocks; four tramp pest species produced three or four reproductives, gnawed long tunnels and two species chose small blocks whereas the other two species chose both blocks; the ninth species, a native pest, was similar to tramp species. Longer tunnels and more replacement reproductives corresponded with pest status, acceptance of small blocks with tramp status. Although counter-intuitive, the foraging acceptance or preference for small blocks of wood corresponds with higher propagule pressure and an increased chance of (unwitting) human assisted transport, and therefore may be an important factor in determining tramp status of drywood termite species. [ABSTRACT FROM AUTHOR]

Recent assessments have shown that capuchin monkeys, like chimpanzees and other Old World primate species, are sensitive to quantitative differences between sets of visible stimuli. In the present study, we examined capuchins’ performance in a more sophisticated quantity judgment task that required the ability to form representations of food quantities while viewing the quantities only one piece at a time. In three experiments, we presented monkeys with the choice between two sets of discrete homogeneous food items and allowed the monkeys to consume the set of their choice. In Experiments 1 and 2, monkeys compared an entirely visible food set to a second set, presented item-by-item into an opaque container. All monkeys exhibited high accuracy in choosing the larger set, even when the entirely visible set was presented last, preventing the use of one-to-one item correspondence to compare quantities. In Experiment 3, monkeys compared two sets that were each presented item-by-item into opaque containers, but at different rates to control for temporal cues. Some monkeys performed well in this experiment, though others exhibited near-chance performance, suggesting that this species’ ability to form representations of food quantities may be limited compared to previously tested species such as chimpanzees. Overall, these findings support the analog magnitude model of quantity representation as an explanation for capuchin monkeys’ quantification of sequentially presented food items. [ABSTRACT FROM AUTHOR]

Even with advances in automated testing techniques, the capuchin monkey (Cebus apella) can be a difficult species to test in the laboratory, given its social/behavioral tendencies and typical activity pattern. Laboratories that maintain social colonies of capuchin monkeys are able to separate and test individuals, but the process can be very effortful and time consuming, and the resulting data can be modest in quantity. The present article describes procedures and apparatuses that were used to train a colony of computer-naive capuchin monkeys to quickly and reliably isolate themselves from group members and interact with a computerized test system in order to produce a large volume of data. Several elements that were important in motivating the monkeys to participate are discussed. [ABSTRACT FROM AUTHOR]

Learning styles in capuchin monkeys were assessed with a computerized reversal-learning task called the mediational paradigm. First, monkeys were trained to respond with 90% accuracy on a two-choice discrimination (A+B-). Then the authors examined differences in performance on three different types of reversal trials (A-B+, A-C+, B+C-), each of which offered differing predictions for performance, depending on whether the monkeys were using associative cues or rule-based strategies. "Performance indicated that the monkeys mainly learned to avoid the B stimulus during training, as the A-C+ condition produced the best performance levels. Therefore, negative stimuli showed greater control over responding after reversal and reflected a more associative rather than rule-based form of learning. [ABSTRACT FROM AUTHOR]

We formulate a mathematical model for food collection and production of workers and nymphs in 2 species of mound building termites. We maximise the number of nymphs (reproductives) produced by each colony over its lifetime with respect to the proportion of eggs that hatch as nymphs as opposed to workers. The results predict that food storage has a very important influence on the pattern of nymph and worker production. Food storage affects the part of the year that nymph production dominates, whether nymphs and workers are produced at the same time or not, and the existence of a final phase in the colony's life when a very large number of nymphs but no workers are produced. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to test whether a pair of tufted capuchin monkeys ( Cebus apella) could generalize their ability to exchange tokens and tool objects with a human experimenter to similar exchanges with a conspecific partner. Monkeys were tested in side-by-side enclosures, one enclosure containing a tool-use apparatus and one or more token(s), and the other enclosure containing one or more tool object(s). The monkeys willingly transferred tokens and tools to a conspecific with little practice. Following a small amount of training, we also found that the monkeys would select situation-appropriate tokens to exchange for specific tools, but did not select appropriate tool objects in response to another monkey’s token transfers. Implications regarding role reversal are discussed. [ABSTRACT FROM AUTHOR]

A tool-throwing task was used to test whether capuchin monkeys understand the difference between functionally appropriate and functionally inappropriate tools. A group of monkeys was trained to obtain a sticky treat from a container outside their enclosure using a projectile attached to one end of an anchored line. Subsequently, these monkeys were given choice tests between functional and nonfunctional versions of tools used in training. A different feature of the tool was varied between alternatives in each choice test. The monkeys chose to use functional tools significantly more often than nonfunctional tools in early exposures to each choice test. A second experiment tested whether these subjects, as well as a second group of minimally trained participants, could distinguish between functional and nonfunctional tools that appeared different from those used in training. A new set of design features was varied between tools in these choice tests. All participants continued to choose functional tools significantly more often than nonfunctional tools, regardless of their tool-throwing experience or the novel appearance of the tools. These results suggest that capuchin monkeys, like chimpanzees studied in similar experiments, are sensitive to a variety of functionally relevant tool features. [ABSTRACT FROM AUTHOR]