Behavior and Ethology Commons^™

Female Acceptance Of Mates Is Consistent Across Different Sex Ratios And Male Proximities In Wood Frog (Rana Sylvatica) Breeding Aggregations, Alia Kabbaj, Laura Bousaid, Gabriella Lowney, Lindsey Swierk

Binghamton University Undergraduate Journal

Sexual selection plays a crucial role in shaping reproductive strategies. We investigated the influence of sex ratio and male proximity on female acceptance of mates in wood frogs (Rana sylvatica). We hypothesized that females at a more even sex ratio would exhibit higher acceptance of males due to reduced male competition when compared to females at a more male-skewed sex ratio. Using digital video analysis of mating trials (n = 39), we quantified male proximity to females and female acceptance of males at two sex ratios – 1:4 (F:M) and 1:7. Males at a 1:4 sex ratio maintained …

The Causes And Consequences Of Behavioral Plasticity In Anti-Predatory Defense And Mate Choice In Tropical Butterflies, Sushant Potdar

Graduate Theses and Dissertations

Behavioral plasticity, where individuals change their behaviors in response to varying environmental and social conditions, affects major evolutionary trajectories. But how individuals change these behaviors under certain social situations, and what the genetic causes and consequences of such behavioral changes are in response to social environments are yet to be fully understood. I address these questions in the context of anti-predatory behaviors (chapter 1), and mate choice (chapters 2, 3, 4) in tropical butterflies. In the context of anti-predatory behaviors, I found predator-specific behavioral changes in toxic Heliconius butterflies, suggesting variance in predation pressures and butterfly recognition of bird calls. …

Solifuge (Camel Spider) Reproductive Biology: An Untapped Taxon For Exploring Sexual Selection, Alfredo V. Peretti, David E. Vrech, Eileen Hebets

Eileen Hebets Publications

The exploration of new and diverse animal groups in the study of sexual selection is both necessary and important to help better understand broad patterns and test sexual selection hypotheses regarding the evolutionary origins and maintenance of reproductive tactics and associated traits. Solifuges are, in this matter, an exceptional group and very little explored from the sexual selection point of view. At first glance, mating is apparently quite simple and conserved within this arachnid order, but solifuge reproductive behavior is unique among arachnids and more diverse than previously thought. In particular, these voracious animals appear to exhibit high sexual conflict, …

Influence Of Testosterone On Male-Male Competition In The Red-Sided Garter Snake, Thamnophis Sirtalis Parietalis, Isabella M. G. Bukovich

Senior Honors Projects, 2020-current

Female mimicry in the red-sided garter snake, Thamnophis sirtalis parietalis, is described in several well-studied evolutionary advantages, but an aspect that remains elusive is how reproductive traits are linked to the 3-fold higher circulating androgens in males with this phenotype. In this study, we implanted male garter snakes (n=15 per group) with either a blank implant (SHAM; control) or a T implant, the latter simulating the female mimic phenotype. Following simulated low-temperature dormancy, males were scored for courtship intensity over three days of behavioral trials with females housed in the same facility. Males were sacrificed, and sperm were collected …

Demonstrating Mate Choice Copying In Spiders Requires Further Research, R. Tucker Gilman, Kasey Fowler-Finn, Eileen A. Hebets

Eileen Hebets Publications

Mate choice copying—when individuals learn to prefer mates or mate types that have been chosen by others—can influence trait evo-lution and speciation (Varela et al. 2018; Dion et al. 2019). Most examples of mate choice copying are from fish, birds, and mammals including humans (Varela et al. 2018). However, 2 invertebrate examples—fruit flies and wolf spiders—have been used to argue that the phenomenon may be phylogenetically widespread, and perhaps the rule rather than the exception in nature (Varela et al. 2018). Here, we revisit the evidence for mate choice copying in wolf spiders (Fowler-Finn et al. 2015) in light of …

Intraspecific Aggression Towards Common Bottlenose Dolphin Calves, Northern Gulf Of Mexico, Errol Ronje, Sarah Piwetz, Heidi Whitehead, Keith D. Mullin

Gulf and Caribbean Research

Infanticide has been widely documented throughout the animal kingdom, and has generally been viewed as an evolved, or adaptive behavior for the perpetrators. Infanticide motivated by increased sexual access to females with calves, or the elimination of potential genetic competition in the form of calf-directed aggression or infanticide, has been proposed for delphinids including killer whales, Indo-Pacific humpback dolphins, Guiana dolphins, and bottlenose dolphins. However, reports of intraspecific aggression towards bottlenose dolphin calves are relatively infrequent, and accounts of confirmed infanticide are rarer still. Reporting instances of intraspecific calf-directed aggression aids researchers to better understand the socio-behavioral context of these …

Traffic Noise And Sexual Selection: Studies Of Anthropogenic Impact On Bird Songs And Undergraduate Student Reasoning Of Evolutionary Mechanisms, Sarah Spier

School of Natural Resources: Dissertations, Theses, and Student Research

Humans have transformed much of the natural landscape and are continuing to do so at an accelerated rate, compromising natural areas that serve as important habitat for many species. Roads impact much of the environment as they fragment habitat and introduce traffic noise into the acoustic environment, deferentially affecting wildlife in roadside habitat. I explored how traffic noise affects the detection of birds based on whether their vocalizations were masked by traffic noise. Masked species detection was not affected by an increase in traffic noise amplitude, while there was a negative effect of traffic noise amplitude on unmasked species detection, …

Achromatic Plumage Patch Quality: Internal Organ And Skeletal Correlates In Aleutian Cackling Geese (Branta Hutchinsii Leucopareia), Matthew D. Delgado

Cal Poly Humboldt theses and projects

Sexual selection theory predicts unique plumage patches signaling quality or status evolve via mate-choice and competition for mates. A growing body of research supports evidence that achromatic plumage patches may act as honest indicators of quality. Irregularities in these patches are attributed to an individual’s phenotypic and genotypic quality as well as environmental wear and tear. Aleutian cackling geese (Branta hutchinsii leucopareia) display achromatic plumage patches on their heads and necks, which may signal information about an individual’s attributes. I tested the honest advertisement and status signaling hypotheses by determining whether size and irregularities in the transition between …

Shaping The Tools Of Battle : Sexual Selection, Contest Dynamics, And Weapon Divergence In The Asian Rhinoceros Beetle Trypoxylus Dichotomus, Jillian F. Del Sol

Graduate Student Theses, Dissertations, & Professional Papers

Exaggerated weapons of sexual selection often diverge more rapidly and dramatically than other body parts, suggesting that relevant agents of selection may be discernible in contemporary populations. I examined the ecology, reproductive behavior, and strength of sexual selection on horn length in five recently diverged beetle populations that differ in relative horn size. I show that mating system ecology differs between these locations and corresponds with the local strength of contemporary selection on horn length. Comparisons of ecological conditions and selection strength across populations offer a critical first step towards meaningfully linking mating system dynamics, selection patterns, and diversity in …

The Roles Of Inter- And Intra-Sexual Selection In Behavioral Isolation Between Native And Invasive Pupfishes, Cory Becher, Jennifer M. Gumm

Faculty Publications

Male-male competition and female mate choice may both play important roles in driving and maintaining reproductive isolation between species. When previously allopatric species come into secondary contact with each other due to introductions, they provide an opportunity to evaluate the identity and strength of reproductive isolating mechanisms. If reproductive isolation is not maintained, hybridization may occur. We examined how reproductive isolating mechanisms mediate hybridization between endemic populations of the Red River pupfish Cyprinodon rubrofluviatilis and the recently introduced sheepshead minnow C. variegatus. In lab-based dominance trials, males of both species won the same number of competitions. However, male C. rubrofluviatilis …

Ecology, Evolution, And Sexual Selection In The Invasive, Globally Distributed Small Indian Mongoose (Urva Auropunctata), M. Aaron Owen

Dissertations, Theses, and Capstone Projects

Introduced species provide rare opportunities to test evolutionary hypotheses in situ by creating so-called natural experiments. Natural experiments are situations in nature that resemble laboratory studies by allowing for comparisons of a “control” group (i.e., a species’ native range) with “experimental” groups (i.e., a species’ introduced range). In particular, introduced animals allow us to investigate evolutionary dynamics in complex, long-lived organisms in ways that would otherwise be impossible in a laboratory setting. One such introduced animal is the small Indian mongoose (Urva auropunctata, formerly Herpestes auropunctatus). Native to South Asia, the small Indian mongoose’s introduction to more …

Sexual Selection, Speciation And Constraints On Geographical Range Overlap In Birds, Christopher Cooney, Joseph A. Tobias, Jason T. Weir, Carlos A. Botero, Nathalie Seddon

Biology Faculty Research

The role of sexual selection as a driver of speciation remains unresolved, not least because we lack a clear empirical understanding of its influence on different phases of the speciation process. Here, using data from 1306 recent avian speciation events, we show that plumage dichromatism (a proxy for sexual selection) does not predict diversification rates, but instead explains the rate at which young lineages achieve geographical range overlap. Importantly, this effect is only significant when range overlap is narrow (< 20%). These findings are consistent with a ‘differential fusion’ model wherein sexual selection reduces rates of fusion among lineages undergoing secondary contact, facilitating parapatry or limited co-existence, whereas more extensive sympatry is contingent on additional factors such as ecological differentiation. Our results provide a more mechanistic explanation for why sexual selection appears to drive early stages of speciation while playing a seemingly limited role in determining broad-scale patterns of diversification.

Increased Insertion Number Leads To Increased Sperm Transfer And Fertilization Success In A Nursery Web Spider, Alissa G. Anderson, Eileen Hebets

Eileen Hebets Publications

Across animals, a male's fitness is largely dictated by his ability to fertilize eggs; and there exists a plethora of male adaptations associated with increasing fertilization success. In the nursery web spider, Pisaurina mira, males restrain females prior to and during copulation by wrapping them with silk. Previous research demonstrates that copulatory silk wrapping reduces a male's chance of being sexually cannibalized and increases the number of sperm transfer opportunities (termed insertions) that a male can achieve within a mating. While avoiding cannibalism provides an obvious survival benefit to males, the impact of insertion number on male fitness remains …

Variation In Female Mating Behavior And Success In The Damselfly, Calopteryx Maculata, Suzanne E. Allison

Masters Theses, 2010-2019

Traditionally, the study of sexual selection has focused on the evolution of elaborate male traits and how they enhance the ability to out-compete other males directly (access to females) and indirectly (access to desirable territories or resources). Female trait studies have focused most on evolved preferences for male traits. While we know much about how sexual selection acts on males, there is a deficit of equivalent study on females. In insects, including damselflies, male size and pigmentation are positively correlated with fat reserves and immune abilities, and therefore with male competitive ability. Here, we show that phenotypic variation that has …

The Maintenance Of Phenotypic Divergence Through Sexual Selection: An Experimental Study In Barn Swallows Hirundo Rustica, Rebecca Safran, Yoni Vortman, Brittany R. Jenkins, Joanna K. Hubbard, Matt Wilkins, Rachel J. Bradley, Arnon Lotem

School of Biological Sciences: Faculty Publications

Previous studies have shown that sexual signals can rapidly diverge among closely related species. However, we lack experimental studies to demonstrate that differences in trait-associated reproductive performance maintain sexual trait differences between closely related populations, in support for a role of sexual selection in speciation. Populations of Northern Hemisphere distributed barn swallows Hirundo rustica are closely related, yet differ in two plumage-based traits: ventral color and length of the outermost tail feathers (streamers). Here we provide experimental evidence that manipulations of these traits result in different reproductive consequences in two subspecies of barn swallow: (H. r. erythrogaster in North …

Proximate And Evolutionary Causes Of Sexual Size Dimorphism In The Crab Spider Mecaphesa Celer, Marie Claire Chelini

School of Biological Sciences: Dissertations, Theses, and Student Research

Animal species’ body sizes result from the balance between selection for survival and selection for reproduction. In species with sexual size dimorphism (SSD), this balance differs between females and males, resulting in distinct sizes despite similar constraints. I used an integrative approach to understand how sexual section, and differences in developmental trajectories and metabolic physiology, resulted in the female biased SSD of the crab spider Mecaphesa celer (Thomisidae). SSD in spiders is often assumed to be a consequence of selection for early male maturation, which should provide males with additional mating opportunities. My results allow us to discard mate …

Benefits Of Size Dimorphism And Copulatory Silk Wrapping In The Sexually Cannibalistic Nursery Web Spider, Pisaurina Mira, Alissa G. Anderson, Eileen Hebets

Eileen Hebets Publications

In sexually cannibalistic animals, male fitness is influenced not only by successful mate acquisition and egg fertilization, but also by avoiding being eaten. In the cannibalistic nursery web spider, Pisaurina mira, the legs of mature males are longer in relation to their body size than those of females, and males use these legs to aid in wrapping a female’s legs with silk prior to and during copulation. We hypothesized that elongated male legs and silk wrapping provide benefits to males, in part through a reduced likelihood of sexual cannibalism. To test this, we paired females of random size with …

A Dual Function Of White Coloration In A Nocturnal Spider Dolomedes Raptor (Araneae: Pisauridae), Tai-Shen Lin, Shichang Zhang, Chen-Pan Liao, Eileen A. Hebets, I-Min Tso

Eileen Hebets Publications

Nocturnal animals frequently possess seemingly conspicuous color patterns that can function in a variety of ways (e.g. prey attraction, camouflage, predator avoidance, etc.). The use of color patterns in intraspecific signaling, especially reproductive activities, in nocturnal animals has received relatively little attention. This study tested for a dual function of color in the nocturnal fishing spider, Dolomedes raptor (Araneae: Pisauridae), whose males develop dimorphic white stripes at sexual maturation. We tested for a role in foraging as well as mate assessment. First, quantifications of the natural variation of male stripes indicated a correlation between stripe area and male body size …

The Role Of Cognition In Sexual Signals And Mate Choice Decisions, Ross Minter

Electronic Theses and Dissertations

Cognitive ability varies dramatically among individuals, yet the manner in which this variation affects reproduction has rarely been investigated. Here, we asked 1) whether male sexual signals reflect cognitive ability and whether females prefer males with superior cognitive abilities, and 2) whether female cognition affects male and female mating decisions? We addressed these questions in a mutual mate choice system, threespine sticklebacks (Gasterosteus aculeatus). We tested cognitive performance by presenting the males and females with a novel task (a barrier to food) to evaluate problem-solving abilities and learning. We found that males that problem solve have elaborate sexual …

Multimodal Signalling In The North American Barn Swallow: A Phenotype Network Approach, Daizaburo Shizuka, Matthew R. Wilkins, Maxwell Joseph, Joanna K. Hubbard, Rebecca Safran

Papers in Behavior in Biological Sciences

Complex signals, involving multiple components within and across modal- ities, are common in animal communication. However, decomposing complex signals into traits and their interactions remains a fundamental challenge for studies of phenotype evolution. We apply a novel phenotype network approach for studying complex signal evolution in the North American barn swallow (Hirundo rustica erythrogaster). We integrate model testing with correlation-based phenotype networks to infer the contributions of female mate choice and male–male competition to the evolution of barn swallow communication. Overall, the best predictors of mate choice were distinct from those for competition, while moderate functional overlap suggests …

Male Brush-Turkeys Attempt Sexual Coercion In Unusual Circumstances, David A. Wells, Darryl N. Jones, David Bulger, Culum Brown

Reproductive Behavior Collection

Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could …

Causes And Consequences Of Female Mate Choice In Drosophila Melanogaster: A Hemiclonal Analysis, Hannah Me Tennant

Theses and Dissertations (Comprehensive)

One of Darwin’s greatest questions, the reason why females prefer elaborate sexually selected male traits and displays, was elucidated by the Fisherian coevolution of male traits and female preferences. While variation in male attractiveness and ornamentation has received much attention, there has been little attempt to evaluate the causes and consequences of intraspecific variation in components of female preference. Furthermore, demonstrating a genetic basis to female preference does not answer the question of how within-population genetic variation is maintained.

Understanding the sources of variation in potential mating interactions between males and females is important because this variation determines the strength …

Fallow Deer Polyandry Is Related To Fertilization Insurance, Elodie F. Briefer, Mary E. Farrell, Thomas J. Hayden, Alan G. Mcelligott

Ethology Collection

Polyandry is widespread, but its adaptive significance is not fully understood. The hypotheses used to explain its persistence have rarely been tested in the wild and particularly for large, long-lived mammals. We investigated polyandry in fallow deer, using female mating and reproduction data gathered over 10 years. Females of this species produce a single offspring (monotocous) and can live to 23 years old. Overall, polyandry was evident in 12 % of females and the long-term, consistent proportion of polyandrous females observed, suggests that monandry and polyandry represent alternative mating strategies. Females were more likely to be polyandrous when their first …

Parasitoid Infestation Changes Female Mating Preferences, Oliver M. Beckers, William E. Wagner

School of Biological Sciences: Faculty Publications

Females often adjust their mating preference to environmental and social conditions. This plasticity of preference can be adaptive for females and can have important consequences for the evolution of male traits. While predation and parasitism are widespread, their effects on female preferences have rarely been investigated. Females of the cricket Gryllus lineaticeps are parasitized by the parasitoid fly Ormia ochracea. Infestation with fly larvae substantially reduces female life span and thus reproductive opportunities of the cricket. Both female G. lineaticeps and flies orient to male song and both prefer male songs with faster chirp rates to songs with slower chirp …

Female Mate Choice For Multimodal Courtship And The Importance Of The Signaling Background For Selection On Male Ornamentation, Jay A. Stafstrom, Eileen A. Hebets

Eileen Hebets Publications

Conspicuous visual ornaments are frequently incorporated into complex courtship displays that integrate signal components from multiple sensory modalities. Mature male Schizocosa crassipes (Walckenaer, 1837) wolf spiders wave, arch, and tap their ornamented forelegs in a visual courtship display that simultaneously incorporates seismic components. To determine the importance of modality-specific signal components in female mate choice, we used a signal ablation design and compared the mating frequency of female-male pairs across signaling environments with manipulated modality-specific transmission properties. We found that the successful transmission of isolated visual or seismic signaling was sufficient for mating success; neither signaling modality was necessary. Additionally, …

Eavesdropping Parasitoids Do Not Cause The Evolution Of Less Conspicuous Signaling Behavior In A Field Cricket, Oliver M. Beckers, William E. Wagner

School of Biological Sciences: Faculty Publications

Males of many species produce conspicuous mating signals to attract females, but these signals can also attract eavesdropping predators and parasites. Males are thus expected to evolve signaling behaviors that balance the sexual selection benefits and the natural selection costs. In the variable field cricket, Gryllus lineaticeps, males sing to attract females, but these songs also attract the lethal parasitoid fly Ormia ochracea. The flies use male crickets as hosts for their larvae, primarily search for hosts during a 2 h period following sunset and prefer the same song types as female crickets. We tested whether males from high-risk populations …

Life History Tradeoffs And Phenotypic Plasticity: The Tale Of A Flight Polyphenic Field Cricket, Chandreyee Mitra

School of Biological Sciences: Dissertations, Theses, and Student Research

Most organisms are resource limited. Such limitations can result in tradeoffs between life history traits -- any traits that affect survival or reproduction. Flight polyphenic field crickets are thought to be a classic example of such a life history tradeoff, in which individuals tradeoff investment in flight capability and investment in reproduction. This polyphenism results from the interaction of two morphological traits: wing morphology (short or long) and flight muscle morphology (functional pink or non-functional white), and is affected by both genes and the environment. I examined life history traits of a flight polyphenic field cricket, Gryllus lineaticeps. First, …

Enigmatic Ornamentation Eases Male Reliance On Courtship Performance For Mating Success, Eileen Hebets, Jay A. Stafstrom, Rafael L. Rodriguez, Dustin J. Wilgers

Eileen Hebets Publications

Female preferences are frequently invoked to explain the widespread occurrence of elaborate male ornaments, yet empirical data demonstrating such preferences are sometimes equivocal or even contradictory. In the wolf spider Schizocosa stridulans, despite evidence of strong female choice, prior research has been unable to link the conspicuous sexually dimorphic foreleg ornamentation of males to their mating success. We conducted three experiments aimed at determining the function of this previously enigmatic ornamentation. Our first two experiments used males with phenotypically modified foreleg phenotypes in simple and complex mating environments in order to examine the relationship between the presence/absence of ornamentation …

Kin Encounter Rate And Inbreeding Avoidance In Canids, Eli Geffen, Michael Kam, Reuven Hefner, Pall Hersteinsson, Anders Angerbjorn, Love Dalen, Eva Fuglei, Karin Noren, Jennifer R. Adams, John Vucetich, Thomas J. Meier, L. David Mech, Bridgett M. Vonholdt, Daniel R. Stahler, Robert K. Wayne

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Mating with close kin can lead to inbreeding depression through the expression of recessive deleterious alleles and loss of heterozygosity. Mate selection may be affected by kin encounter rate, and inbreeding avoidance may not be uniform but associated with age and social system. Specifically, selection for kin recognition and inbreeding avoidance may be more developed in species that live in family groups or breed cooperatively. To test this hypothesis, we compared kin encounter rate and the proportion of related breeding pairs in noninbred and highly inbred canid populations. The chance of randomly encountering a full sib ranged between 1–8% and …

Multimodal Courtship Efficacy Of Schizocosa Retrorsa Wolf Spiders: Implications Of An Additional Signal Modality, Aaron S. Rundus, Roger D. Santer, Eileen Hebets

Eileen Hebets Publications

Here, we simultaneously examine both content and efficacy-based sources of selection on the visual and seismic multimodal courtship display of the wolf spider Schizocosa retrorsa. Immature field-collected S. retrorsa were reared in the laboratory on either high-quantity diet (HD) or low-quantity diet (LD) treatments. On maturation, females of each diet treatment were run in simultaneous mate choice trials with both a HD and an LD male (content-based selection). Simultaneous mate choice trials were conducted across different signaling environments (efficacy-based selection) in a fully crossed 2 × 2 design with visual treatments of light/dark (visual signal present/absent) and seismic treatments …