|Inter-Individual Variation and Individual Behavior Development: Phylogenetic and Ontogenetic Factors|
|Saturday, May 26, 2018|
|3:00 PM–3:50 PM |
|Marriott Marquis, Grand Ballroom 10-13|
|Area: PCH/EAB; Domain: Translational|
|Chair: Christina Nord (University of Lethbridge)|
Behavioral phenomena both result from and contribute to the workings of natural selection. Phylogenetic selection as a causal mechanism has revolutionized our understanding of the origin of various phenotypes (observable characteristics) within and across animal species. The discovery that behavior also acts as a phenotypes in phylogenetic evolution has greatly enriched a thoroughgoing theory of behavior and afforded the opportunity to discover the relationships between ontogenetic and phylogenetic selection. Ontogenetic and phylogenetic selection require variation from which to select and are constrained by multiple variables. For example, behavioral repertoires are constrained by an individual's neuroanatomy and environment; ontogeny and phylogeny interact to select and constrain response systems. Additionally, variation, selection, and constraints act across populations of individuals, which can result in stable population-level phenotypes despite variation at the individual level. Measures of "personality" in the animal behavior literature exemplify a focus on this population-level consistency by measuring behavioral phenotypes relative to the population's repertoire. Here, we aim to synthesize fieldwork with a theoretical analysis focusing on phylogenetic and ontogenetic selection in order to better understand how a selectionist approach can inform research on and interpretation of behavioral phenomena.
|Instruction Level: Intermediate|
|Keyword(s): evolution, neuroscience, plastisity, selection|
|The Interaction of Phylogenetic and Ontogenetic Selection Processes|
|APRIL M. BECKER (University of North Texas)|
|Abstract: Selection stands as an alternative to essentialist thinking and as a causal frame for current forms within biology and behavior. When originally discovered, selection was thought to work only on the level of phylogenetic evolution. When genes were discovered, their power to potentially work as a substrate for both heredity and variation, which are necessary for natural selection to occur, earned them an exclusive role in evolutionary thought for a long time. Yet since that time, massive advances in the field have uncovered other mechanisms of heredity and variation, and selection-based causal mechanisms within single lifetimes have been uncovered. This talk will review the minimal relationships that are necessary for a system of selection to arise, the varieties of entities and events that fill these necessary roles in various systems of selection, and the interconnectedness between different levels of selection. Information garnered from evolutionary biology, development, epigenetics, ethology, and behavior analysis will be synthesized to demonstrate how a comprehensive understanding of the relationships between ontogenetic and phylogenetic selection can inform research and interpretation of behavioral phenomena. Our current understanding of selection continues to undergo revision as the complexity of evolutionary processes further come to light.|
|Rapid Inhibition of Competing Behavior within a Response System: A Neuro-Operant Analysis|
|DANIELE ORTU (University of North Texas)|
|Abstract: The behavioral repertoire has been described as a set of environment-behavior relations acquired during the lifetime of the organism. Within that conceptualization, a response system can be considered as a neuroanatomically and ontogenetically constrained and defined subset of environment-behavior relations. For instance, given the anatomical organization of the human vocal apparatus, humans seem to be able to emit a single vocal response at any given time. Conversely, based on the anatomical organization of human arms and hands, multiple responses can be emitted concurrently, and, within each hand, each finger can potentially respond independently from the others, provided that the organism learns to move the fingers independently. The interaction between ontogeny and phylogeny is discussed in relation to physiologically constrained response systems and Palmer’s (2009) concept of the repertoire, according to which shifts in current stimulus control determine what is the dominant response within each response system. Neural mechanisms that ensure rapid winner-take-all response selection are described with a special focus on how inhibition of competing responses is possible within very short time-frames.|
Measuring Individual Variation in Wild Vervet Monkeys: How Do Populations Emerge From Individuals?
|CHRISTINA NORD (University of Lethbridge), S. Henzi (University of Lethbridge), Louise Barrett (University of Lethbridge)|
Variation within and across populations is a necessary component of natural selection, and within-subject variation is a necessary component of behavioral selection. In the animal behavior literature, "boldness" is a measure of the propensity of animals to approach novel stimuli. Boldness is considered to be a measure of animal behavior "personality." Personality measures investigate individual behavioral differences in a population and are predicted to be consistent through time. Here, we examined whether wild vervet monkeys (Chlorocebus pygerythrus) responded similarly to the presentation of novel food items. Individual responses toward novel food items were recorded for 106 individuals in three troops of free-ranging vervet monkeys residing in a private game reserve in South Africa. Replication trials were conducted for a subset of individuals, and the data were analyzed for consistency at both population and individual levels. Our data indicate that boldness was consistent both within age and sex classes, as well as at the population level (repeatability), while being less so within individuals (replicability). Implications of these findings are discussed with respect to both behavioral and natural selection.