It is a pleasure to announce this year's ABS research grants. As always, we received far more applications than we could fund and the decision process was complicated by a consistently high standard. Proposals covered a gamut of questions, in a wide array of taxa, and tackled both fundamental theoretical problems and important applied ones. Many of the ideas were highly original, demonstrating the extraordinary intellectual fecundity of our community.
A committee of 11 ABS members volunteered their time to assess proposals. I was fortunate to be able to match each grant with an expert in the relevant research area. After a difficult ranking process, funds were sufficient to support 38 proposals of the 129 received, a success rate of 29%. These include the E. O. Wilson Conservation Award at $1,000. There was no award this year in the Cetacean Behavior and Conservation category.
I should like to thank Andrew Barron, Darren Burke, Ken Cheng, Paul McDonald, John Eadie, Ximena Nelson, Doug Mock, Diana Perez, John Prenter and Phil Taylor for their thoughtful reviews; Shan Duncan and Steve Ramey for their splendidly efficient administrative system; and the many ABS members who have kindly donated funds to this program.
The Edward O. Wilson ABS Student Research Grant for Conservation supports a proposal considered meritorious for its science and conservation component. E. O. Wilson, professor at Harvard University, who in 2002 received the ABS Distinguished Animal Behaviorist Award, is one of the world's most eminent scientists and pioneers in biodiversity conservation.
Predation risk can have a profound impact on the behaviour of animals and on the dynamics of ecological communities. Changes in prey behaviour intended to mitigate risk from predators (e.g. selection of safer habitats during periods of high predator density) can cascade through lower trophic levels; therefore, elucidating the nature and extent of predation risk effects on prey behaviour is central to understanding and conserving communities in their natural state. Large sharks, such as the tiger shark (Galeocerdo cuvier), are major predators of marine turtles in some systems, yet non-lethal effects of shark presence on turtle behaviour have not been investigated. Here, I propose to determine whether two species of marine turtle, the green turtle (Chelonia mydas) and loggerhead turtle (Caretta caretta), alter their diving behaviour and habitat choices in response to seasonal fluctuations in tiger shark density in the shallow sand-seagrass ecosystem of Shark Bay, Western Australia.
Total Amount Awarded:: 1000.00
Sexual selection, typically comprised of male-male competition and female choice, is not solely limited to precopulatory scenarios. Once insemination occurs, males may continue to compete via their sperm, while females may impose bias toward a particular male via cryptic female choice. Traits used by females to judge potential mates prior to copulation are often well understood; however, it is less clear what cues females receive following insemination that enables them to exert fertilization bias. Furthermore, it is poorly understood what types of benefits females gain by choosing one male over another once she mates multiply. This study will examine mate choice decisions in guppies (Poecilia reticulata) in both pre- and postcopulatory trials. The main hypothesis tested is that female guppies prefer males that possess a higher number of major histocompatibility complex (MHC) class-IIB alleles. In doing so, she will be acquiring genetic benefits for her offspring, since they will thus possess a broader spectrum of antigen recognition tools. In order to test this hypothesis, the number of alleles in a portion of MHC class-IIB will be measured for all study individuals. Females will be presented with a high and low MHC class-IIB diversity male in a precopulatory mate choice trial. These males will also be matched for proportion of orange coloration and standard length. Mating will be prohibited. This study will incorporate a postcopulatory mate choice test as well. It is critical to control for the effects of sperm competition in order to test for the presence of cryptic female choice. Following mate choice trials, the sperm from both males will be stripped and inseminated in equal concentrations into the focal female. Once she produces her brood, paternity will be determined using microsatellites proven to be polymorphic in guppies. The results of this study will reveal three main points: 1) whether MHC-dependent mate choice occurs in guppies; 2) whether females use the same cues prior to and following insemination; 3) whether cryptic female choice occurs in guppies.
Total Amount Awarded:: 500.00
In the family Syngnathidae (seahorses and pipefishes), females deposit their unfertilized eggs into male brood pouches where embryos are carried until independence (Vincent and Sadler 1995). Thus, only males can provide postzygotic care to the offspring, and certainty of paternity is very high (Masonjones and Lewis 2000). As predicted by traditional theory concerning sexual selection and parental care (Trivers 1976), many Syngnathid species exhibit reversed sex roles, with females displaying sex-limited ornamentations and competing more aggressively for mates (Matsumoto and Yanagisawa 2001; Wilson, Ahnesjo et al. 2003). However, the most derived of this family, seahorses (genus Hippocampus) (Wilson, Ahnesjo et al. 2003) exhibit strong paternal care but do not show such obvious signs of sex-role reversal, making this genus ideal for studying the relationship between sex roles, PI, and the evolution of mating systems. Here, I propose to assess the mating system and sex roles of Floridian populations of Hippocampus erectus, using microsatellites to determine maternity of male broods and opportunity for selection (I) (Shuster 2003; Kvarnemo 2006) and selection differentials (Kvarnemo 2006) as a measure of the strength of sexual selection. These techniques will allow me to determine if this species remains faithful to a single partner throughout the breeding season, as has been found with most other seahorse species, and investigate what factors may influence sex differences in the strength of sexual selection. Finally, I plan to document a previously observed sex difference in skin projections known as fronds, which may be a result of sexual selection on females and have a potential role in male mate choice.
Total Amount Awarded:: 970.00
In a noisy world, acoustically communicating organisms experience selection pressure to maximize signal transmission. The concave-eared torrent frog, Amolops tormotus, and the hole-in-the-head frog, Huia cavitympanum, live adjacent to streams that produce broad-spectrum background noise. These two species are the only anurans known to possess sunken tympanic membranes that are embedded deep in the skull at the base of 'ear canals', similar to those of mammals. This extraordinary peripheral auditory adaptation is hypothesized to contribute to the ability of A. tormotus to perceive ultrasonic conspecific call elements, which facilitates intraspecific communication amid high-level acoustic interference. Amolops tormotus is the first non-mammalian vertebrate found to communicate in ultrasounds. The auditory behavior of H. cavitympanum, however, remains uncharacterized. Given the intriguing similarity of the H. cavitympanum and A. tormotus ambient acoustic environment and external auditory morphology, we hypothesize that these species have converged on the use of ultrasonic communication to bypass broad-spectrum environmental noise. This study will examine the acoustic behavior of H. cavitympanum in its natural environment, providing data for comparative research on the auditory behavior and the frequency-dependent response properties of H. cavitympanum and A. tormotus. This research may inform us of fundamental evolutionary, ecological and physiological attributes that confer high-frequency hearing sensitivity in all forms.
Total Amount Awarded:: 500.00
Postcopulatory sexual selection is sexual selection that occurs during or after copulation. It plays an important role in polygamous species, where the number of copulations does not necessarily predict reproductive success (Parker 1970, Simmons 2001). Cryptic female choice is a mechanism of post-copulatory sexual selection in which female-controlled processes that occur after copulation bias paternity by males with a particular trait over others (Eberhard 1996). A tractable approach to studying cryptic female choice is to relate male performance in copulatory courtship to processes in females which bias sperm usage towards males that perform that courtship. In Merosargus cingulatus (Diptera: Stratiomyidae), males defend territories on oviposition sites used by females and perform copulatory courtship. In a pilot study, when males were manipulated so that they were unable to perform copulatory courtship, females left the territory without ovipositing after mating. When males were not manipulated, they performed copulatory courtship and the female laid eggs before leaving the territory. Here I propose to demonstrate that females are less likely to oviposit immediately after mating when the male does not perform copulatory courtship compared to situations in which he does perform courtship. I will also determine if there is last male sperm precedence in this species, i.e., if the last male to mate with a female sires most of her offspring (Birkhead 1999). Last male sperm precedence would indicate that the females can bias their sperm usage by timing their oviposition, giving a male that performed copulatory courtship a greater reproductive success.
Total Amount Awarded:: 975.00
Functionally referential signaling (FRS) is well known in vertebrates, particularly primates, whereby individuals transfer information to conspecifics regarding categorical environmental events, such as the presence and types of predators and food. I propose to study FRS in insects, for which there is currently limited anecdotal evidence, and whose presence in insects would imply considerable complexity in communication. I will test three criteria for FRS in the African weaver ant, Oecophylla longinoda, and species of North American paper wasp, Polistes spp. By creating colonies of the latter species with different genetic structures, I will also be able to test how FRS varies with relatedness, a phenomenon which has never been studied before.
Total Amount Awarded:: 500.00
I will examine the ontogeny of species recognition using a model organism for studies of sexual selection and auditory behavior. The two main thrusts of this proposal include an examination of behavioral recognition for the advertisement call of the tungara frog (Physalaemus pustulosus) in developing froglets, and secondly a neural study of functional mapping of the central auditory system during development and how changes here correlate with changes in recognition behavior. This proposal attempts to bridge the ontogeny of a critical life history decision in reproductive adults with the developing nervous system that is preparing the organism for this future event.
Total Amount Awarded:: 500.00
Mate guarding is a mating strategy commonly found in crustaceans and it represents an interesting case of intersexual behavioral conflict. The initial idea that mate guarding is the 'optimum allocation of time' spent by males with a female versus searching for other females is correct, but incomplete, because it doesn't take into account the role played by females. The optimal guarding time for males commonly does not coincide with the optimal time for females to be guarded, and the actual guarding time is a compromise reached between the two sexes. I plan to measure separately the optimal guarding time for each sex and compare it to the compromised guarding time, in order to test theoretical models. Clam shrimp represents a unique system, because they comprise dioecious and androdioecious species. Androdioecy is a mixed mating system, where males coexist with hermaphrodites, and there are no true females. Androdioecious species are facultatively unisexual. If the costs of mate guarding are too high to the hermaphrodite, the hermaphrodite has the alternative to self fertilize, changing the optimal guarding time for both sexes. For this reason clam shrimp could be considered a novel and uniquely informative model system to test mate guarding models and investigate intersexual conflicts.
Total Amount Awarded:: 500.00
Parrots are famous for their mimetic abilities, but because they are difficult to observe in the wild little is known about how and why vocal learning evolved in this group. This project explores the function and development of vocal learning in one of the best known parrot species. For the past two decades Green-rumped Parrotlets (Forpus passerinus) have been studied each year in Venezuela resulting in a marked population of hundreds of known individuals and a unique opportunity for studying parrot vocal identity. Contact calls are the most widely used vocalization and may function as vocal signatures used to coordinate reproductive activities. We will conduct playback experiments to incubating females located inside nest boxes to test if they are capable of distinguishing their mates' calls from non-mates. Once established the plausibility of vocal signatures in adults we will study the process of signal acquisition in nestlings. State-of-the-art audio-video technology will be used to monitor nestling vocal repertories throughout development to determine whether parental templates influence emerging vocal identities. Playback experiments will be conducted to test whether adults and nestlings can distinguish each others' calls and at what stage in development this occurs. Because parrots are disproportionately threatened, a better understanding of the learning phase in wild parrots could be helpful to reintroduction programs of threatened species. This project will complete two decades of demographical monitoring and help avoid a discontinuation in data collection during an unprecedented period of climate change for parrots.
Total Amount Awarded:: 400.00
To determine the extent of spatial knowledge of a marine fish with limited adult movement, I propose to conduct displacement experiments using the European long snouted seahorse (Hippocampus guttulatus). By displacing and tracking seahorses, I will be able to first determine their range of familiarity (mental map) and second to identify strategies they employ to either return to the home site (when within their mental map) or to locate suitable habitat (when beyond their mental map). The results of such experiments have potential significance in understanding how sedentary animals perceive their habitat, whether the increased connectivity of marine habitats versus terrestrial habitats has an impact on spatial perception, and how threatened seahorse populations may be effected by disturbance events.
Total Amount Awarded:: 1000.00
Competition over breeding territories can be intense when there are more sexually mature individuals than available breeding territories. This situation may lead to the development of a sub-population of non-breeders, called a floater population. Using removal experiments, I propose to determine whether or not a floater sub-population exists within a population of Eastern Kingbirds (Tyrannus tyrannus). If a population of both male and female floaters can be shown to exist, it would strongly suggest that the amount of habitat is limiting the population size of kingbirds. Understanding the factors limiting avian populations is crucial if our aim is to reverse the decades long declines of many migratory species.
Total Amount Awarded:: 500.00
Archerfish have an unusual hunting technique: they spit at insects, knocking them down onto the water surface for consumption. At least when young, these fish forage in social groups and kleptoparasitism is common- the fish that spits an insect down is not necessarily the fish that consumes it. This competitive dynamic leads to questions of foraging roles, their distribution, their effect on group size and stability, and the evolution of spitting and social foraging in general. Within a foraging group, some fish may specialize in spitting (producers) while some in prey stealing (scroungers). The proposed research will discern whether stable producer-scrounger roles exist in social archerfish, whether adopted roles are a function of dominance status, and how group size affects the frequency and effectiveness of each role. In addition, this research will explore the dynamics of stable group size within an archerfish population and compare these findings to the predictions of producer-scrounger models. Archerfish provide an excellent study system because dynamics such as group size, dominance structures, and prey input rates can be easily manipulated within the lab environment. Additionally, producing events, theft events, and payoffs are all easily measurable. The archerfish study system thus offers great flexibility and control to explore and test current social foraging theories and expand basic knowledge of forces that shape social behavior in animals.
Total Amount Awarded:: 852.00
When parents provision more than one dependent young, parents and offspring may disagree about the division of limited resources. The resolution of this conflict will depend on the balance of power between parents and offspring. The proposed experiment examines how nest architecture can influence the extent to which offspring can control resource allocation, and how the balance of power shifts during the nesting cycle.
Total Amount Awarded:: 490.00
My dissertation study examines two types of sexual conflicts in ecological context. My study species, Serranus tortugarum (Serranidae: Serraninae), is a small simultaneously hermaphroditic coral reef fish that engages in 'egg parceling,' subdivision of the egg clutch for exchange with a mating partner. Egg parceling can increase opportunities for male-role matings when an individual is able to fertilize more egg parcels than it produces; thus parceling rate may be used as an indicator of the intensity of intra-pair sexual conflict across different environments. Another behavior called 'streaking' is frequently used to gain extra paternity by intruding on other spawning pairs and releasing sperm. The intensity of extra-pair conflict over streaking may be reflected by shifts in male (gonadal) allocation with changing levels of sperm competition. My field research explores how parceling strategy and male allocation vary over a range of densities and with differing mating opportunities and costs. Results from models and field data for this study have generated two hypotheses about the effects of density on sex allocation and the effects of mating opportunities and costs on egg-parceling strategy: 1. Where local density is high, number of streakers per spawn will be high, and the resulting sperm competition should increase male allocation, and 2. When costs associated with mating are low and the chance of finding a mate is high, pair fidelity should decrease and parceling should increase. To date, I have demonstrated a strong relationship between local density and streaking activity, and shown that local density explains much of the variation in sex allocation across reefs. I propose to further examine the effects of density using controlled experiments and to examine effects of mate availability and mating costs on egg-parceling strategy.
Total Amount Awarded:: 1000.00
The proposed studies test the extent to which behavioral profiles, also known as behavioral syndromes or non-human animal personality, affect behavior in a socially and vocally complex avian species. The study species, Carolina chickadees, Poecile carolinensis, possesses large repertories of easily recordable vocal and non-vocal behavior linked to social contexts. Chickadees are an ideal system for the proposed research studies because they have a complex social structure and a highly complex and diverse vocal communication system. The research described here investigates individuals' behavior across a variety of diverse contexts, while explicitly manipulating the social context. Findings from the described studies provide answers to social, developmental, and comparative questions of behavior.
Total Amount Awarded:: 500.00
This is an investigation about acoustic communication in felids. The object of this project is description and analysis of vocalization in four felids species, realization playback experiments that permit inferred about individual recognition. Studies in acoustic communication in felids have pointed in descriptive analysis up till now and in only the lion have a playback studies in vocalization. The results of this investigation can been applicator in management species.
Total Amount Awarded:: 500.00
Sexual selection is widely recognized as the selective force which best explains the evolution of elaborate traits in animals. Ornate traits such as the peacock tail are thought to be selected for through competition for access to mates, most often between males. However, because females are less likely to compete for mate access, this mechanism does not sufficiently explain female trait elaboration. Recent work has suggested a broadening of sexual selection theory to include not only competition for access to mates, but female competition for reproductive resources and/or reproductive opportunity to conceive or raise young. While the elaborate song of male songbirds is an influential model system for the study of sexual selection, few studies have investigated selective pressures for female song, which may be more common that previously thought. Understanding elaborate female song could be a key step towards explaining how sexual selection acts on females. I recently discovered that Stripe-headed Sparrow females show more pronounced song and singing behavior than males; this suggests that these females are experiencing strong sexual selection. I propose to determine 1) the function of elaborate female song in Stripe-headed Sparrows, 2) how sexual selection influences female singing behavior, and 3) the competitive pressures that select for this elaborate female trait.
Total Amount Awarded:: 1000.00
Interspecific territoriality, or territory defense against other species, is uncommon in temperate regions, yet it is possibly widespread in tropical habitats. Moreover, interspecific behaviors could be key in explaining tropical species distributions and the partitioning of species among habitats. Previous work along a successional gradient in lowland Amazon forest demonstrated that, in birds, interspecific territoriality shapes the local distributions of more than 20 genera of birds and creates patterns of species replacement, in which early stages of the gradient were occupied by one member of a congener pair and later stages were occupied by the other. Similar patterns of species replacement are common in other tropical animal communities, and especially along altitudinal gradients. I propose to conduct heterospecific song playback experiments with eight bird species (representing three genera) on the Pacific slope of the Tilarán mountain range in Costa Rica to determine whether interspecific territoriality is operating at range boundaries of congeners with species replacements along an altitudinal gradient. In addition, I will use playbacks both at range limits and within altitudinal ranges of species to determine whether this behavior depends upon the proximity of individuals to their range boundaries with congeners. This research will also analyze behavioral responses to playback stimuli to understand how territorial signals (e.g., song in birds) may differ when directed at conspecifics versus congeners.
Total Amount Awarded:: 975.00
Elaborate male signals and displays can increase the conspicuousness of males to females in addition to serving as indicators of male quality, thus acting to increase mating success. In addition to attracting the attention of females, however, these signals may increase detectability to potential predators. Male courtship communication in the wolf spider Schizocosa ocreata includes a visual leg-waving display augmented by tufts of bristles on the first pair of legs. As S. ocreata are sympatric with a number of generalist predators including other species of spiders, toads and birds, these traits may increase risk of predation. The proposed study aims to characterize the importance of avian predation on spider survival in the field and test the responses of spiders to avian cues through lab studies using audio playback. I will also investigate the potential for increased predation risk based on the size of a visual signal (secondary sexual character), using video playback to test the hypothesis that traits/displays increasing conspicuousness of males to females increase the risk of detection by avian predators. This work will provide further evidence for the hypothesis that evolution of sexually-selected traits which increase male conspicuousness to females is constrained by the cost of increased detection by predators, and thus contribute to our understanding of the evolution of communication.
Total Amount Awarded:: 500.00
The environment varies in both biotic and abiotic factors throughout a breeding season. Studies examining phenotypic plasticity have shown that individuals alter their development when exposed to different environments. The majority of the studies examining phenotypic plasticity have focussed on individual responses to abiotic factors, ignoring biotic factors such as population demographics that are known to change selection pressures. The goal of this study is to examine how population demographics change throughout a breeding season as a function of differences in male and female maturity rates. I will also examine whether there are any associated changes in selection pressures, and whether this dynamic variation in selection alters male developmental and behavioral strategies. To examine these questions, I will use a ubiquitous jumping spider (Phidippus clarus) that has synchronous female maturity and a continuous male maturity. This project will provide a new understanding of how fluctuating population demographic factors can change selection on plasticity in male behaviors and morphology, and will provide a better understanding of how traits associated with male quality can change throughout a breeding season.
Total Amount Awarded:: 500.00
Patterns of parental care evolve in concert with mating systems and theory predicts that the resulting reproductive decisions of males and females involve tradeoffs between investment in parental effort and mating effort. Approximately 90% of all bird species are socially monogamous but regularly practice individual promiscuity in the form of clandestine 'extra-pair'fertilizations (EPFs). This study experimetnally tests the hypothesis that male Yellow Warbler (Dendroica petechia) parents practice a "mixed" reproductive strategy, where levels of parental care are adjusted in accordance with (1) their certainty of paternity in their own brood, and (2) the concurrent opportunities to gain EPFs with females other than their social mate.
Total Amount Awarded:: 1000.00
The fly Ormia ochracea are acoustic parasitoids of crickets. Adult flies are free-living while their larvae must develop as internal parasites in crickets. To find appropriate host crickets, gravid females must perform two auditory tasks: they must recognize and localize the calling songs that male crickets produce. Both of these auditory tasks require Ormia to process temporal information as time differences in acoustic cues arriving at each convey information for sound source location and time intervals within calling song structure contain information important for host recognition. In laboratory studies flies can localize individual sources accurately, but may fail to do so when flies are presented with multiple attractive sound sources that mask important temporal cues required for recognition and localization. The field studies proposed here will address the important question of whether flies face the same difficulties in finding host crickets in nature and whether or not crickets take advantage of source masking to avoid parasitism.
Total Amount Awarded:: 1000.00
The dominance system is an important component of social, group-living animals in that it affects many life-history variables such as foraging success, reproductive success, and mortality (Pruetz and Isbell 2000, Clutton-Brock 1988, Sapolsky 2005). The specific focus of this proposal is the evolution and function of female dominance, i.e. the ability of all females to elicit submissive behaviors from all males (Kappeler 1993). One area of research that may shed light on the potential functions of female dominance is the development and acquisition of female dominance in infants and juvenile lemurs. Studying the dominance relations of immature individuals with their peers, as well as with adult individuals, will better inform the function of female dominance by elucidating the age at which females become dominant to males. For example, if all females suddenly become dominant to males during their first mating season, this will support the idea that reproduction may be a function of female dominance. In addition, studying the social behaviors associated with this transition will illuminate which behavioral components are important for females to become dominant to males. The current project focuses on ring-tailed lemurs, which are the most social of the extant lemur species. Ring-tailed lemurs are an ideal study species because they are diurnal, live in large groups ranging from 5 to 27 individuals, and are the most terrestrial of the lemur species, spending about 30% of their time on the ground (Sauther et al. 1999). The project is a comparative study of ring-tailed lemurs in their natural habitat in Madagascar and on St. Catherine's Island off the coast of Georgia, USA and is the first study to observe immature individuals from two sites through multiple periods of their development, i.e. infancy and juvenility. Data were collected during 2005 and 2006 in Madagascar, and will be compared to data collected during 2006 and 2007 on St. Catherine's Island. This study is focusing on the differences in development and acquisition of dominance at both sites and particularly how earlier age at first reproduction affects the development of female dominance in immature individuals. Data are collected on adult animals to determine how the dominance system is maintained through adulthood and whether differences exist at the two sites. In addition to behavioral observations, fecal samples are collected from all individuals and assayed for cortisol and testosterone concentrations. The ultimate goal of the project is to utilize behavioral and hormonal data from immature and adult individuals at both sites to better understand the factors affecting the development, acquisition, and maintenance of the female dominance system in ring-tailed lemurs to elucidate the potential functions and evolution of this dominance system.
Total Amount Awarded:: 1000.00
I recently discovered a population of jumping spider (Araneae: Salticidae) in the Neotropics that exploits the well-known mutualism between ants (Pseudomyrmex spp.) and acacias (Acacia spp.) The spider does not feed upon ants or nectar, but rather harvests and ingests the protein- and lipid-rich Beltian bodies from acacia leaf tips. I propose to conduct a series of observational and experimental studies in the field in an attempt to understand this novel, peculiar phenomenon and its functional relation to the ant-acacia mutualism as a whole.
Total Amount Awarded:: 950.00
Primates are unique among placental mammals in that they possess trichromatic color vision, while most mammals are dichromatic (red-green color blind). However, unlike Old World primates, for which trichromacy is uniform among all individuals, most New World monkeys have polymorphic color vision (several trichromat and dichromat phenotypes present in the population). The polymorphic opsin gene found in these primates is thought to be maintained via balancing selection, although the mechanism remains unclear. Current research provides evidence that efficient foraging may select for both trichromatic and dichromatic vision phenotypes among Neotropical primates. I propose to evaluate the importance of color vision to white-faced capuchins, a polymorphic species, for detecting and selecting the fruit and insects that compose their diet. I will assess whether individuals are differentially able to find and acquire food and whether foraging pressures can explain the evolution and maintenance of this polymorphism. Understanding evolutionary processes that maintain variation in animal populations is of considerable interest to evolutionary biologists and ecologists and my research will contribute to this growing body of knowledge.
Total Amount Awarded:: 1000.00
While bright animal colors have been the subject of intense study for several decades, colorants such as melanins or pterins that are produced de novo by their bearers remain controversial and poorly understood. We present a tractable system for better understanding the evolution of exaggerated color ornamentation involving such pigments: pterin-based wing coloration in the Cabbage White Butterfly, Pieris rapae. We propose a series of behavioral assays to elucidate the signaling function of bright, sexually dichromatic, pterin-based wing colors in P. rapae. These studies will complement ongoing research probing the genetic and environmental determinants of variation in pterin-based coloration in both sexes of this butterfly species.
Total Amount Awarded:: 1000.00
Animals showing evidence of heightened stress measured by amount of circulating stress hormones (glucocorticoids) also show a propensity for increased alarm calling behavior even in the absence of predators. However, it has not been shown that the increased alarm calling is a function of elevated glucocorticoids or is an independent response. This project will manipulate glucocorticoid concentrations in free ranging California ground squirrels (Spermophilus beecheyi) to test the hypothesis that alarm calling behavior is influenced by stress levels. The prediction is that squirrels under greater chronic stress will alarm call more frequently those under less stress.
Total Amount Awarded:: 500.00
Individual distinctiveness is critical for many behaviors that occur within groups of social animals, so the evolution of individual distinctiveness may be intimately related to the evolution of sociality itself. The proposed study will determine the degree to which individual vocal distinctiveness and social group size evolve together, using the alarm calls of ground-dwelling sciurid rodents (ground squirrels, prairie dogs, and marmots) as a model system. The animals will be live-trapped and marked, and their alarm calls will be recorded. The calls will be analyzed via computer, on which acoustic characteristics will be measured from multiple calling bouts of each individual. The amount of individually-distinctive information content in each species' calls will be calculated using a method based on information theory. This information statistic will be regressed against group size or social complexity in a phylogenetically corrected manner to see if individual distinctiveness and sociality evolve together. Three non-mutually exclusive hypotheses will be tested, all addressing the manner in which individual distinctiveness may evolve with sociality. Preliminary results support the study's predictions. The final results will contribute a vital piece to the puzzle of social evolution and enhance our understanding of individuality in social behavior.
Total Amount Awarded:: 500.00
Neuroecological studies have suggested a link between the structural habitat complexity, life history, neuroanatomy, and behavioral flexibility of an organism. I propose a study of the interactions between ecology, neuroanatomy, and behavioral flexibility in closely related species of Anolis lizards in order to test the hypothesis that behavioral flexibility and brain morphology are correlated. To achieve this goal, I will measure relative overall brain size and the relative size of the reptilian hippocampus, an area associated with spatial memory and learning, in six species of Anolis lizards. I will determine the level of spatial complexity of the habitat occupied by each species. In order to determine the level of behavioral flexibility of each species, I will conduct focal observations of their ability to solve detour problems as well as field experiments using a maze in order to test these species' ability to make spatial decisions.
Total Amount Awarded:: 500.00
Chorusing frogs often vary characteristics of their advertisement calls with social context. It is unclear, however, whether response to such signals also varies with social context. I plan to examine whether response to advertisement calls of different durations varies with social context in gray tree frogs, Hyla chrysoscelis. Call duration is a highly variable property within males of this species, and males increase call durations with increasing chorus density. A call of given duration therefore conveys different information depending on the chorus density in which that call is given. Because of the likely fitness consequences for both male and female receivers of responding to calls of different durations relative to other chorus members, I propose that individuals account for chorus density when responding to any given call. I propose to determine whether male and female receivers adjust assessment rules, and respond differently to advertisement calls of different durations in different chorus densities. I will test this prediction by a series of playback tests for males, and phonotaxis tests for females. These tests will examine response to a focal stimulus (either a long or short call) in different natural and simulated chorus densities. I expect to find that both males and females respond differentially to the same call depending on the chorus environment in which that call is heard.
Total Amount Awarded:: 500.00
I propose to examine the social organization of Elephas maximus, the Asian elephant, and the role that vocal communication plays in maintaining it. Little is known about vocal communication in fission-fusion and multi-tiered societies, where individuals are not repeatedly found together with the same companions. Asian elephants have a diverse vocal repertoire, fluid social dynamics, and large home range. These characteristics create challenges in group cohesion and coordination that vocal communication may help overcome. Virtually nothing is known about the social behavior and vocalizations of Asian elephants in the wild except that they appear to be female-bonded. It has been suggested that they form smaller, less stable social associations than African savannah elephants, Loxodonta africana, which are strongly female-bonded. Since E. maximus is one of only three extant species of elephantids and is globally endangered, this study is of basic scientific as well as conservation value. In addition, this large-brained mammal constitutes an important comparative system to African elephants, as well taxa outside the Proboscidean clade, for investigating the evolution of animal communication and sociality.
Total Amount Awarded:: 500.00
Recent behavioral studies indicate that social cues can critically influence avian settlement patterns. Integrating this knowledge with other aspects of habitat selection provides a clear opportunity to broaden our conceptual understanding of fine-scale distribution patterns. My proposed research will: 1) identify and characterize potential social settlement cues in a non-territorial avian system, 2) determine the strength of the relationship between social cues and habitat quality, 3) demonstrate how social cues and settlement patterns may vary among habitat areas, and 4) experimentally manipulate auditory and reproductive public information cues to test explicit hypotheses regarding social cues and their stimulatory effect.
Total Amount Awarded:: 500.00
Parental effort is the total costs to adults in caring for all offspring and is largely a function of the amount of food provided to offspring and defense of young. A risky form of parental care is brood defense. Studies show that the intensity of defense often increases with offspring age potentially because the value of offspring to parents increases as offspring become closer to reproductive age. Parents may also vary the level of defense depending on the risk the predator poses to the adults. Most studies of parental defense examine how defense changes up until offspring leave the nest despite the fact that the post-fledging period is the time of greatest offspring value. Tests of parental defense are derived in large part from temperate birds. Tropical birds are ideal for testing theory because they have contrasting life histories and environments than most temperate species. Because of high nest predation in tropical birds, once offspring fledge, they are of extreme value to parents. Therefore tropical birds may exhibit different patterns of defense during the post-fledging period than what is predicted based on temperate species. I propose to study how parental defense changes during the incubation, nestling, and post-fledging periods. In particular, I will address how defense changes between fledging and offspring independence, a previously unstudied period. With the long length of post-fledging parental care in my study species, a unique opportunity is available to test theory on how defense changes throughout the post-fledging period and how the different life history traits of tropical birds influence parental defense.
Total Amount Awarded:: 1000.00
Interspecific competition is one of the key processes structuring communities, but has rarely been demonstrated. Migratory birds may be a good group for such studies because they inhabit different communities during the breeding and nonbreeding seasons, lessening selective pressures that would reduce competition. Moreover, the influx of these migratory 'winter residents' into the established community produces an annual natural experiment that allows testing of hypotheses. The American Redstart is an excellent model species for a study of interspecific competition because its wintering ecology is relatively well known. We have some evidence that interspecific competition for insects may occur in Puerto Rico, particularly between redstarts, Adelaide's Warblers and anole lizards. As redstarts return to Puerto Rico each fall, they could integrate into the insectivore community using several strategies. The strategy used can be identified using a multiple-hypothesis testing framework (Figure 1). This study will significantly contribute to our understanding of the wintering ecology of migratory songbirds.
Total Amount Awarded:: 1000.00
Host contact patterns are arguably the most important factor governing infectious disease spread in animal populations (McCallum et al. 2001; Begon 2002). My dissertation research integrates fundamental ecological principles with issues related to wildlife management and anthropogenic change. I will use pathogens affecting feral swine populations in the United States as a model system to investigate three main questions: (1) How do host contact patterns and dispersal influence pathogen spread and evolution? (2) How do landscape-level changes, including agricultural land use, affect pathogen prevalence and strain variation? (3) How does human culling of feral animals influence local prevalence and impacts of disease?
Total Amount Awarded:: 1000.00