Behavior and Ethology Commons^™

The Complexities Of Wolf Spider Communication: Exploring Courtship Signal Function In Rabidosa Rabida, Dustin J. Wilgers

Dissertations and Theses in Biological Sciences

Evidence of signal complexity is seemingly pervasive across animal communication systems. Exploring signal function may provide insight into how these displays evolved and are maintained. This dissertation examines the courtship signal function in a grassland wolf spider. Rabidosa rabida lives in an extremely complex environment, and males use complex displays incorporating both visual and seismic modalities. Using several approaches I provide insight into the content and efficacy of the various signal components, as well as how variation in these displays influence female mating decisions in isolation and combined.

First, I manipulated male and female body condition using diet quantity manipulations …

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 …

Analytic And Numerical Studies Of A Simple Model Of Attractive-Repulsive Swarms, Andrew S. Ronan

HMC Senior Theses

We study the equilibrium solutions of an integrodifferential equation used to model one-dimensional biological swarms. We assume that the motion of the swarm is governed by pairwise interactions, or a convolution in the continuous setting, and derive a continuous model from conservation laws. The steady-state solution found for the model is compactly supported and is shown to be an attractive equilibrium solution via linear perturbation theory. Numerical simulations support that the steady-state solution is attractive for all initial swarm distributions. Some initial results for the model in higher dimensions are also presented.

Does Group Feeding By Toxic Prey Confer A Defensive Benefit? Aristolochic Acid Content, Larvae Group Size And Survival Of Pipevine Swallowtail (Battus Philenor) Larvae., Lauren Wisner Wilmoth

Masters Theses

Aggregative feeding is widespread in Lepidopteran larvae suggesting that this

behavior serves on adaptive function. Many studies of the potential benefits of

aggregative feeding in Lepidopteran larvae have been conducted. However, no studies

have directly examined the benefits of cryptic larvae being both chemically defended and

gregarious. Group feeding occurs disproportionately more in chemically defended

larvae than in larvae that have no chemical defense. Most of these larvae are cryptic

when they are most highly aggregated and most vulnerable to predation. In this study,

the benefits of group feeding in terms of decreased predation were explored in first instar

larvae …

Assortative Mating In Fallow Deer Reduces The Strength Of Sexual Selection, Mary E. Farrell, Elodie Briefer, Alan G. Mcelligott

Veterinary Science and Medicine Collection

Background: Assortative mating can help explain how genetic variation for male quality is maintained even in highly polygynous species. Here, we present a longitudinal study examining how female and male ages, as well as male social dominance, affect assortative mating in fallow deer (Dama dama) over 10 years. Assortative mating could help explain the substantial proportion of females that do not mate with prime-aged, high ranking males, despite very high mating skew. We investigated the temporal pattern of female and male matings, and the relationship between female age and the age and dominance of their mates.

Results: The peak of …

More Ornamented Males Exhibit Increased Predation Risk And Antipredatory Escapes, But Not Greater Mortality, Kasey D. Fowler-Finn, Eileen Hebets

Eileen Hebets Publications

Secondary sexual traits not only confer benefits to their bearer through increased mate acquisition, but may also have inherent costs, including the attraction of predators. Here, we examined the relationship between conspicuous secondary sexual traits and predation costs using two male morphs of Schizocosa wolf spiders: brushlegged and non-ornamented. In the field, we ran two predation experiments using artificial enclosures to directly test mortality costs of predation on the two male morphs. Using a natural predator, a larger wolf spider in the genus Hogna, we found no difference in predation on brush-legged vs. non-ornamented males. However, predation was depends …

Mechanisms For Decisions About The Future, Jeffrey R. Stevens

Jeffrey Stevens Papers & Publications

Evolutionary and psychological perspectives on decision making remain largely separate endeavors. The bounded rationality approach integrates these two perspectives by focusing on simple, plausible mechanisms of decision making and the cognitive capacities needed to implement these mechanisms. Decisions about the future provide a class of decisions that lend themselves to a bounded rationality approach. Though many different mechanisms may exist for making decisions about the future, only a subset of these mechanisms actually require a representation of the future. The bounded rationality approach helps focus on the cognitive capacities and decision mechanisms that are necessary for a full understanding of …

Evidence Of Cowbird Parasitism On Yellow-Throated Warblers At Starved Rock State Park, Illinois, Usa, Joseph Traina

Faculty Publications & Research

An adult yellow-throated warbler (Dendroica dominica) was observed feeding a fledged brown-headed cowbird (Molothrus ater) on July 1, 2010 at the Beehive Overlook at Starved Rock State Park (LaSalle County, Illinois, USA). Food in the form of captured insects was brought to the young cowbird five times during a period of approximately 15 minutes.

Signs Of Mood And Anxiety Disorders In Chimpanzees, Hope Ferdowsian, Debra Durham, Charles Kimwele, Godelieve Kranendonk, Emily Otali, Timothy Akugizibwe, J. B. Mulcahy, Lilly Ajarova, Cassie Meré Johnson

Sentience Collection

Background: In humans, traumatic experiences are sometimes followed by psychiatric disorders. In chimpanzees, studies have demonstrated an association between traumatic events and the emergence of behavioral disturbances resembling posttraumatic stress disorder (PTSD) and depression. We addressed the following central question: Do chimpanzees develop posttraumatic symptoms, in the form of abnormal behaviors, which cluster into syndromes similar to those described in human mood and anxiety disorders?

Methodology/Principal Findings: In phase 1 of this study, we accessed case reports of chimpanzees who had been reportedly subjected to traumatic events, such as maternal separation, social isolation, experimentation, or similar experiences. We applied and …

Qualitative Behavioural Assessment And Quantitative Physiological Measurement Of Cattle Naïve And Habituated To Road Transport, C. A. Stockman, T. Collins, A. L. Barnes, D. Miller, S. L. Wickham, D. T. Beatty, D. Blache, F. Wemelsfelder, P. A. Fleming

Veterinary Science and Medicine Collection

The present study examined whether observers could distinguish between cattle that are naïve to road transport and the same cattle after becoming more habituated to transport. The behavioural expression of cattle was assessed through the method of qualitative behavioural assessment (QBA), and these assessments were correlated with various physiological parameters. Fourteen Angus steers were assessed during their first road trip and then again on their ninth trip, 15 days later. Blood samples were collected immediately before and after transport, and heart rate and core body temperature were measured continuously throughout each trip. Video footage recorded during each trip was edited …

Current Status And Future Directions Of Research In Complex Signaling, Eileen Hebets

Eileen Hebets Publications

The term ‘complex signaling’ reflects a recent scientific focus on the multiple elements frequently incorporated into animal signals (reviewed in Candolin, 2003; Hebets and Papaj, 2005; Partan and Marler, 2005; Bro-Jorgensen, 2010). It embodies a new appreciation that signals used in communication are regularly composed of numerous components and that each component may individually vary in a number of ways. For example, signal components may vary in their time or mechanism of production, in the efficacy of their transmission, and/or in their mechanism of reception, among others. Employing the term ‘complex signaling’ reminds us of the need to maintain a …

Females Are Choosier In The Dark: Environment-Dependent Reliance On Courtship Components And Its Impact On Fitness, Aaron S. Rundus, Laura Sullivan-Beckers, Dustin J. Wilgers, Eileen Hebets

Eileen Hebets Publications

A broad understanding of multimodal courtship function necessitates knowledge of the potential information content of signal components, the efficacy of signal components in eliciting the appropriate receiver response, and the fitness consequences of mating decisions based upon various signal components. We present data addressing each of these requirements for the multimodal-signaling wolf spider, Schizocosa floridana Bryant. Using diet manipulations, we first demonstrate that both visual and seismic courtship signals are condition-dependent. Next, using high- and low-quantity diet individuals in mate choice trials across manipulated signaling environments, we demonstrate that the seismic signal is crucial for mating success and further show …

A Sticky Situation: Solifugids (Arachnida, Solifugae) Use Adhesive Organs On Their Pedipalps For Prey Capture, Rodrigo H. Willemart, Roger D. Santer, Andrew J. Spence, Eileen Hebets

Eileen Hebets Publications

Solifugids (Arachnida, Solifugae) have unique evertable adhesive organs on the tips of their pedipalps, named ‘suctorial’ or ‘palpal’ organs. Previous studies have shown that these organs enable solifugids to climb smooth glass-like surfaces and have hypothesized that these structures facilitate prey capture. Here, we use high-speed videography to demonstrate that the suctorial organs of Eremochelis bilobatus are its primary means of capturing insect prey. We also present calculations of the adhesive pressure exerted by these suctorial organs during real prey capture events.

Chemical Communication In A Multimodal Context, Eileen A. Hebets, Aaron S. Rundus

Eileen Hebets Publications

All animals are equipped with multiple sensory systems (e.g., visual, chemical, acoustic, tactile, electrical, thermal), and signals perceived via these sensory systems facilitate communication. Such communication often involves displays that incorporate more than one signal from more than one sensory modality, resulting in multimodal signaling. The number of empirical and theoretical studies addressing issues of multimodal signaling is ever-increasing and this chapter highlights why crustaceans, as a taxonomic group, are ideal for advancing such studies. Early classifications of multimodal signaling sought to categorize signal components as either redundant or nonredundant, while more recent classifications lay out specific hypotheses relating to …

The Degree Of Response To Increased Predation Risk Corresponds To Male Secondary Sexual Traits, Kasey Fowler-Finn, Eileen Hebets

Eileen Hebets Publications

Secondary sexual traits are expected to reflect a balance between sexual selection and natural selection. We test the hypothesis that plasticity in sexual advertisement behaviors can influence this trade-off, allowing showier traits than expected for a given level of predation risk. Specifically, we tested whether the degree of behavioral plasticity exhibited in response to chemical cues of a co-occurring predatory wolf spider corresponds to courtship rate and the degree of ornamentation in male wolf spiders. Both ornamented (brush-legged) males and non-ornamented males decreased locomotion, decreased their likelihood to court, and increased their time to initiate courtship in response to predator …

An Evolutionary Psychology Perspective On Responsibility Attributions For Infidelity And Relationship Dissolution, Kindra Lynn Edmonson

Theses Digitization Project

This study investigated responsibility attributions for a partner's emotional infidelity and for a partner's sexual infidelity, and the likelyhood that the victim or partner would end the relationship. This study found a significant relationship between responsibility attributions for a romantic partner's unfaithfulness and the likelihood the relationship would end: the stronger the attributions of personal responsibility the more likely the relationship would dissolve.

The Scientific Classification Of Wolves: Canis Lupus Soupus, L. David Mech

USGS Northern Prairie Wildlife Research Center

Gray wolf, timber wolf, red wolf, eastern wolf, brush wolf, arctic wolf, Mexican wolf, maned wolf, Ethiopian wolf, etc., etc. How many kinds of wolves are there? And what are the differences? This is a really good question, and the answer is getting more complicated all the time. Let us start by going back a few years to the way science looked at wolves more traditionally— before the days of the new field of molecular genetics. Molecular genetics examines the actual DNA of animals and tries to classify them according to genetic similarities. ...

What does all this mean in …

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

USGS Northern Prairie Wildlife Research Center

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 …

Use Of Cranial Characters In Taxonomy Of The Minnesota Wolf (Canis Sp.), L. David Mech, Ronald M. Nowak, Sanford Weisberg

USGS Northern Prairie Wildlife Research Center

Minnesota wolves (Canis sp.) sometimes are reported to have affinity to a small, narrow-skulled eastern form (Canis lupus lycaon Schreber, 1775) and sometimes to a larger, broader western form (Canis lupus nubilus Say, 1823). We found that pre-1950 Minnesota wolf skulls were similar in size to those of wolves from southeastern Ontario and smaller than those of western wolves. However, Minnesota wolf skulls during 1970–1976 showed a shift to the larger, western form. Although Minnesota skull measurements after 1976 were unavailable, rostral ratios from 1969 through 1999 were consistent with hybridization between the smaller eastern wolf and …

Wolves, Canis Lupus, Carry And Cache The Collars Of Radio-Collared White-Tailed Deer, Odocoileus Virginianus, They Killed, Michael E. Nelson, L. David Mech

USGS Northern Prairie Wildlife Research Center

Wolves (Canis lupus) in northeastern Minnesota cached six radio-collars (four in winter, two in spring-summer) of 202 radio-collared White-tailed Deer (Odocoileus virginianus) they killed or consumed from 1975 to 2010. A Wolf bedded on top of one collar cached in snow. We found one collar each at a Wolf den and Wolf rendezvous site, 2.5 km and 0.5 km respectively, from each deer’s previous locations.