Genetic diversity and mate selection in a reintroduced population of gray wolves

The genetic composition of an individual can markedly affect its survival, reproduction, and ultimately fitness. As some wildlife populations become smaller, conserving genetic diversity will be a conservation challenge. Many imperiled species are already supported through population augmentation efforts and we often do not know if or how genetic diversity is maintained in translocated species. As a case study for understanding the maintenance of genetic diversity in augmented populations, I wanted to know if genetic diversity (i.e., observed heterozygosity) remained high in a population of gray wolves in the Rocky Mountains of the U.S. > 20 years after reintroduction. Additionally, I wanted to know if a potential mechanism for such diversity was individuals with below average genetic diversity choosing mates with above average diversity. I also asked whether there was a preference for mating with unrelated individuals. Finally, I hypothesized that mated pairs with above average heterozygosity would have increased survival of young. Ultimately, I found that females with below average heterozygosity did not choose mates with above average heterozygosity and wolves chose mates randomly with respect to genetic relatedness. Pup survival was not higher for mated pairs with above average heterozygosity in my models. The dominant variables predicting pup survival were harvest rate during their first year of life and years pairs were mated. Ultimately, genetic diversity was relatively unchanged > 20 years after reintroduction. The mechanism for maintaining such diversity does not appear related to individuals preferentially choosing more genetically diverse mates. Inbreeding avoidance, however, appears to be at least one mechanism maintaining genetic diversity in this population.

Mate Selection Behavior of GED Recipients

The General Educational Development (GED) degree is designed to be a credential equivalent to the high school diploma. However, growing evidence indicates that GED recipients have worse outcomes than high school graduates. Such findings raise the question: is the GED socially equivalent to the high school diploma? Although educational assortative mating patterns have long been used as a barometer of the social distance across educational groups, there has not been a study that has addressed this question by examining the marital sorting patterns of GED recipients. Using log-linear models, our study shows that the odds of intermarriage between GED recipients and high school graduates resemble those between GED recipients and those without a secondary degree. Racial/ethnic minorities had greater difficulty crossing the GED/high school graduate boundary when they married. Our findings detract from the purported view that the GED degree is equivalent to a traditional high school diploma.

Sexual and individual signatures are encoded in the temporal rate of Cape gannet display calls

Vocalisations play a vital role in animal communication, as they are involved in many biological functions. Seabirds often breed in large and dense colonies, making successful recognition between mates or between parents-and offspring crucial for reproductive success. Most seabird species, including Cape gannets (Morus capensis), are monomorphic and likely rely on acoustic signals for mate selection and mate recognition. This study aimed to better understand the use of vocalisations for sex and individual recognition in Cape gannets by describing the acoustic structure of their display calls at the nest. Vocalisations of nesting Cape gannets were recorded and acoustic measurements were extracted in both temporal and frequency domains. Values of the fundamental frequency and the average of Inter-Onset-Interval appeared to be the most important acoustic variables for sex determination. Both temporal and frequency parameters showed a potential for individual identity coding, with the average units Inter-Onset-Interval being the most important variable for individual identification for both sexes. This study provides the first evidence of sex-specific and individual vocal signatures in adult breeding Cape gannets. From an applied perspective, identified sex specific differences could potentially be used as a non-invasive method for field-based sex-determination in research and monitoring projects on Cape gannets.

Effects of parasitism on antipredatory responses and defensive behaviors in the subterranean rodent Ctenomys talarum.

Predation represents an important evolutionary force shaping specific adaptations. Prey organisms present behavioral adaptations that allow them to recognize, avoid and defend themselves from their predators. In addition to predation, there is a growing consensus about the role of parasitism in the structuring of biological communities. In vertebrates, the effects on hosts include changes in daily activity, feeding, mate selection, reproduction, and modifications in responses to environmental stimuli. These behavioral variations can benefit the parasite (parasitic manipulation), benefit the host, or appear as a side effect of the infection. We evaluated the influence of parasitism on the behavioral and physiological response of Ctenomys talarum (Thomas 1898) to predator cues. We found that individuals exposed to cat odors and immobilization entered less often and stayed less time in the transparent arms of elevated maze, exhibiting a preference for protected areas (anxiogenic response). Additionally, we evaluated if the presence of parasites affected antipredatory behaviors in tuco-tucos (naturally parasitized, deparasitized or inoculated with Eimeria sp.). We did not find differences among the groups as regards responses to predator cues. Therefore, while exposure to predator cues triggered a stress response, the manipulation of parasite loads did not modify homeostasis under these experimental conditions.

Online Dating in New Zealand: Why and how do people use Tinder?

<p>Online dating is becoming increasingly popular all over the world. However there is a dearth of research investigating online dating in New Zealand. The research presented here explores the prevalence of online dating in New Zealand, examining motivations, attitudes and outcomes associated with online dating (Study 1). It also investigates mate selection in an online dating context using a simulation of the popular mobile dating app, Tinder (Study 2). In Study 1, students from Victoria University of Wellington completed a survey developed by the author along with scales measuring individual differences on ideal standards and sociosexual orientation. As predicted, Study 1 found that online dating is prevalent in this sample (especially using Tinder), attitudes towards it were generally positive, and those using it more were more likely to be single, more sociosexually unrestricted, and rate physical attractiveness as more important in potential partners. Study 2 investigated the use of Tinder more specifically through an experimental simulation of this mobile dating app. Participants were presented with series of attractive and unattractive faces and asked to indicate whether they would hypothetically seek further contact (click heart icon to the right of the face) or uninterested (click cross icon to the left of the face). Response times and selections were recorded. As expected, men selected more faces than women, and responded equally rapidly regardless of the attractiveness of the face. In contrast, women responded significantly faster to the unattractive faces than the attractive faces. Results were predicted and interpreted in light of parental investment theory and in the context of prior research on both online dating and speed dating.</p>

Online Dating in New Zealand: Why and how do people use Tinder?

<p>Online dating is becoming increasingly popular all over the world. However there is a dearth of research investigating online dating in New Zealand. The research presented here explores the prevalence of online dating in New Zealand, examining motivations, attitudes and outcomes associated with online dating (Study 1). It also investigates mate selection in an online dating context using a simulation of the popular mobile dating app, Tinder (Study 2). In Study 1, students from Victoria University of Wellington completed a survey developed by the author along with scales measuring individual differences on ideal standards and sociosexual orientation. As predicted, Study 1 found that online dating is prevalent in this sample (especially using Tinder), attitudes towards it were generally positive, and those using it more were more likely to be single, more sociosexually unrestricted, and rate physical attractiveness as more important in potential partners. Study 2 investigated the use of Tinder more specifically through an experimental simulation of this mobile dating app. Participants were presented with series of attractive and unattractive faces and asked to indicate whether they would hypothetically seek further contact (click heart icon to the right of the face) or uninterested (click cross icon to the left of the face). Response times and selections were recorded. As expected, men selected more faces than women, and responded equally rapidly regardless of the attractiveness of the face. In contrast, women responded significantly faster to the unattractive faces than the attractive faces. Results were predicted and interpreted in light of parental investment theory and in the context of prior research on both online dating and speed dating.</p>

Acquisition of a Learned Operant and Critical Flicker-Fusion Rate in the Tuatara (Sphenodon spp.)

<p>Scientific investigation of the sensory world and behavior of the tuatara is limited. This study incorporates both ecological and psychological perspectives to test learning and visual perception using a novel operant technique and flicker-fusion rates to measure visual discrimination in tuatara. We posed four main questions: (1) can a reliable method examine learning and visual perception in tuatara?, (2) what is the critical flicker-fusion (CFF) rates for tuatara and how does it relate to motion detection ability?, (3) can stimulus control be transferred to a Y-maze from an open field arena?, and (4) what are the implications for behavioral ecology, conservation, and species welfare? Tuatara (Sphenodon punctatus) were trained using an operant conditioning procedure with food reinforcement to respond to discriminative stimuli (S+) of various flicker-fusion rates, and ignore a non-discriminative stimulus (S-). Tuatara discriminated CFF rates between 2.65-45.61 Hz, but not at 65.09 Hz. The upper threshold between 45.61-65.09 Hz is comparable to other mammalian, avian, and herpetological species. Tuatara demonstrated a learning capacity for acquisition of an operant task as well as cognitive development for learning and memory strategies. Visual discrimination is important to tuatara and may facilitate behavioral responses to many context-dependent ecological processes (i.e., predator/prey/kin recognition, mate selection, environmental discrimination, optimal foraging strategies, and communication). By understanding the importance of visual stimuli, the study provides a better perspective of the tuatara natural sensory world. Additionally, a reliable method was established that can be used for more comprehensive psychophysical experiments to further access visual perception and learning in all reptiles, with the potential to examine other sensory mechanisms such as audition, chemoreception, and tactility.</p>