SIRE Speakers

 

SIRE is honored to have researchers present their ideas at our meetings. The following speakers have given or are scheduled to give talks:

Bailey House

Prosocial and Reciprocal behavior in Chimpanzees and Human Children

Scheduled: February 10, 2011 at 6:00pm           Location: TSU Ontiveros B

Abstract

Despite the fact that humans are more cooperative than chimpanzees (Pan troglodytes), our closest living relatives, the cooperative behavior of these two species is similar in that individuals often cooperate with unrelated individuals. Reciprocity provides an evolutionary explanation for cooperation among non-relatives because it provides a strategy for cooperators to direct benefits preferentially towards other cooperators, who will likely return those benefits in kind. This account would predict that ‘prosocial’ behavior that confers benefits on others should be associated with reciprocal behavior, and a considerable amount of research has sought to explore this connection in chimpanzees. This research have been largely inconsistent in its findings, but the results of some laboratory experiments suggest that chimpanzees do not take advantage of low-cost opportunities to prosocially deliver food to group members, and they also do not adopt contingently reciprocal strategies inside these experimental contexts. Comparing how humans behave in similar tasks will illuminate differences between these two species that might underlie differences in cooperation between these species. In this talk I will present new empirical studies of prosocial and reciprocal behavior in human children, experiments that were designed to be comparable to those with chimpanzees. This work adds to our understanding of two important questions. (1) How does prosocial and reciprocal behavior differ between humans and chimpanzees? (2) How do these behaviors develop over childhood, and how are their developmental trajectories related? These studies suggest possible reasons why humans may be more cooperative than chimpanzees, and they also provide insight into the ontogenetic development of that cooperative behavior.

Dr. Aaron Goetz

Scheduled: February 24, 2011

Dr. Craig LaMunyon

Sperm Competition Causes the Evolution of Large Sperm in Nematodes.

Scheduled: March 10, 2011

 

Dr. Kayla Causey

Evolutionary Developmental Psychology: How an appreciation of psychological ontogeny informs our understanding of human nature (the case of deontic reasoning in children)

Scheduled: March, 24 2011                               Location: LH 308

Abstract

Evolutionary Developmental Psychology (EDP) is the study of how natural selection shaped human development. It assumes that childhood behaviors and cognitions are the product of natural selection, designed to prepare children for adulthood and/or help them thrive in their current stage of development. I describe why a functional approach to development informs our understanding of children's behavior. In addition, I discuss how an understanding of ontogenetic processes (development within an individual) can inform our understanding of our species' phylogeny (changes in a species over evolutionary time). Specifically, I describe preliminary results indicating that 5-year-olds' and adults' privileged reasoning in the social contract domain is not "innate" but develops from a broad predisposition to attend to socially relevant information in preschool, which facilitates the development of deontic reasoning about social obligations.

Adrienne Mora

Sick but sexy? Manipulation of host sexual signals for parasite transmission

Scheduled: April 7, 2011

Abstract

Many parasites alter host phenotype to enhance their transmission and fitness, a phenomenon known as “host manipulation.” Manipulations may be subtle, such as increased activity levels, or spectacular, such as performance of complex, aberrant behaviors. Parasites transmitted from prey to predators (trophically transmitted parasites, or TTPs) often intensify “risky” intermediate host behaviors to enhance susceptibility to predatory definitive hosts. These parasites are generally under strong selection to optimize transmission by predation as they can only sexually reproduce within the predatory definitive host. While we know that TTPs can increase some risky behaviors in intermediate hosts to complete their life cycles, little is known about the relationship between TTPs and host sexual signaling. Sexual selection often involves risky behaviors, such as elaborate courtship displays; these sexual signals are intended to attract mates, but can also draw unwanted attention from predators. While parasites often negatively influence the ability of hosts to attract mates and reproduce, TTPs could operate in the opposite way. Such parasites may intensify conspicuous sexual characters that make hosts more attractive to predators, but also to prospective mates. A seemingly paradoxical outcome could result, as hosts would experience a short-term increase in mating success along with increased predation risk. The “sick but sexy” hypothesis counters conventional parasite-mediated models of sexual selection, which posit that sexually selected signals have evolved to advertise parasite resistance and good health. To test this hypothesis, I initiated an observational field study to examine the relationship between parasitism and sexual signaling in a population of fiddler crabs naturally infected with TTPs. After statistically controlling for environmental factors, male courtship effort increased with increasing abundance of the Probolocoryphe uca trematode, suggesting a link between rate of host sexual signaling and infection with a TTP.

Dr. Andrew Delton

Welfare Tradeoffs: Computation, Reciprocity, and Social Emotions

Scheduled: April 21, 2011

Abstract

Members of social species routinely make decisions that involve welfare allocations—decisions that impact the welfare of two or more parties. These decisions often involve welfare tradeoffs such that increasing one organism’s welfare comes at the expense of another organism’s welfare. In this talk, I present preliminary evidence that the mind computes a variable—a welfare tradeoff ratio—that is used to regulate this kind of social decision-making. By consulting this variable, an organism can determine when it is and is not appropriate to cede personal welfare on behalf of another. I also summarize an initial empirical test of the role of welfare tradeoff ratios in reciprocity and how the emotions of anger and gratitude might function to recalibrate welfare tradeoff ratios within reciprocal relationships. The larger theme of this talk is that thinking in terms of neurocomputational variables such as welfare tradeoff ratios helps to explain how complex behaviors—such as cooperation, generosity, and aggression—can arise from a physical device such as the human brain.

Rebecca Frank

The role of contingent reciprocity and market exchange in the lives of female olive baboons

Scheduled: May 5, 2011                                       Location: SGMH1113 @ 5:00pm

Abstract

Evolutionary theory predicts that cooperation among nonkin will be limited to reciprocating partners who monitor the balance of trade within their relationships in order to prevent cheating. However, recent data suggest that primates mainly exchange low-cost commodities, like grooming, over short time scales, frequently alternating roles to minimize the risk of being cheated. Short-term trades are regulated in a biological market, commodity values are set following the laws of supply and demand, and individuals choose to trade with the partner offering the highest value. Individuals maximize their immediate benefits without having to monitor the balance of their exchanges over time. Applied to primate grooming exchanges, a market model predicts that females will balance the amount of grooming they trade within single bouts when all partners offer similar value. When some partners can offer other valuable benefits, a market model predicts they will trade with who ever offers the most grooming in return. Thus, females are predicted to trade grooming for access to resources when feeding competition is elevated and rank differences translate to differential foraging success. Females are also predicted to trade grooming with mothers of young infants in exchange for access to the infant. Analysis of grooming among wild adult female olive baboons in Chololo, Kenya suggest that female baboons are capable of monitoring their exchanges over time and can trade across some currencies, but it is not clear that market pricing explains the observed patterning of exchange.