Lecture D2 (2024-09-26): Modes of Communication [BAD AUDIO]

UNFORTUNATELY, THERE WAS SOME PROBLEM WITH THE RECORDING SETUP IN THE ROOM. IRONICALLY, THE AUDIO DOES NOT SEEM TO BE WORKABLE IN THIS VIDEO ABOUT ACOUSTIC COMMUNICATION.

In this lecture, we discuss the major modes of communication and spend some time discussing how animals use these different modalities to signal each other. This lecture focuses on a variety of communication mechanisms across the modalities and how they might have been co-opted from existing mechanisms that were adapted for other functions. After discussing tactile, chemical, acoustic, visual, and electric communication, we close with a brief discussion of multi-modal signals.

Topic highlights:

• the four major communication modalities (plus electricity)
• exploration of tandem running as a behavior employing simultaneous bi-directional communication between ants
  • both tactile and olfactory communication
• examples of olfactory/chemical communication
  • discussion of the origins of the "tandem calling" signal as co-option of the poison/venom gland in the sting
  • definition of the semiochemicals: pheromones, allomones, kairomones, and synonomes
  • categories of different pheromones: volatile and headspace, non-volatile and contact
  • cuticular hydrocarbons (CHC's) on insects and their evolution for desiccation mitigation and then communication
• primer and releaser signals
• examples of acoustic communication
  • amplitude, frequency, and the perception of different frequencies at different amplitudes by a receiver
  • stridulation (and scrapers and files)
  • tymbal
  • semantic communication in monkey alarm calls
  • danger of noise corruption in acoustic signals
• examples of visual communication
  • use of color, countershading, bioluminescence, counter-illumination
• examples of electric communication in weakly electric fish
  • electrolocation and communication
  • comparison to evolution of the poison gland for communication
• multi-modal communication (and redundant signals as a subset of multi-modal communication)

Important terms: communication mode/modality, antennae, semiochemical, pheromone, allomone, kairomone, synomone, volatile pheromones, headspace, contact/non-volatile pheromones, cuticular hydrocarbon (CHC), primer, releaser, stridulation, frequency, complex sound waves are viewed as sums of many different frequencies of simple oscillating sound waves, amplitude, tymbal, multi-modal communication

Lecture D1 (2024-09-24): Communication and Its Evolution

In this lecture, we will introduce basic theories of communication and the evolution of communication in animal behavior. We focus on the relationship between communications and signals as well as how signals can evolve from cues and then be further elaborated with stereotypy and redundancy (possibly leading to multi-modal communication). This also gives an opportunity to introduce autocommunication, public information, and eavesdropping.

Topic highlights:

• the relationship between a communicating pair of sender and receiver and the signals between them
  • the distinction between a signal and a cue
  • autocommunication
• the evolution of communication/signaling
  • cue ritualization, noise, stereotypy, and redundancy
• visual semaphoring by some animals
• opportunities for exploiting communication
  • public information and eavesdropping

Important terms: communication, signal, cue, ritualization, stereotypy, redundancy, autocommunication, co-option, exaptation, noise, semaphore/sempahoring, public information, eavesdropping, concealment, private information, multimodal communication

Lecture C3 (2024-09-19): Cognition

In this lecture, we address perspectives on animal behavior that explain animal motivation by use of latent, unobservable structures. We start by exploring drive theory and the hydraulic models of drive from early ethology and use that to pivot to an introduction of cognition and the separation of the physical "brain" and the metaphorical "mind." Such a "mind" can do things like: being aware of itself in context of a larger world, be aware of the mind and motivation of others and use this information to drive its own behavior, predict future events based on past experience, and so on. We present cognition as an unobservable mechanism behind behavior, but we also discuss the risks of this approach to confounding proximate and ultimate explanations of behavior as well as the risks of false conclusions about animal intelligence due to a lack of ecological relevance in some standard tests of cognition and intelligence. Ultimately, we recognize that despite the risks, cognitive models can be formative in the process of forming research questions, and they provide one way to incorporate animal motivation into hypotheses about behavior (which would otherwise be difficult to do based on what can be outwardly observed alone).

Topic highlights:

• drive theory and motivational explanations for animal behavior [Chapter 4]
  • hydraulic models of drive
  • displacement behavior, redirected behavior, self-directed behavior
  • repetitive, stereotyped behaviors
• cognition and the mind/body distinction
  • awareness of the "self"
  • theory of mind
  • "mental time travel" / forecasting
• examples of apparently cognitive behavior in non-human animals (note: not an exhaustive list)
  • time–place learning
  • gaze following
  • caching and thievery
  • self and the mirror test
• risks of taking an anthropomorphic, cognitive perspective
  • risk of confounding proximate mechanisms and ultimate causation
  • umwelt and ecology; why should a lobster recognize itself in a mirror?
    • are standard tests of cognition/intelligence equally relevant to all animals?
    • do we need different versions of cognition for different umwelten?
• risks of not considering cognition
  • no room for "motivation"

Important terms: drive theory, displacement behavior, redirected behavior, self-directed behavior, stereotyped behaviors, cognition, theory of mind, time–place learning, gaze following, cache thievery, the mirror test, motivation

Lecture C2 (2024-09-17): Learning in Animal Behaviors

In this lecture, we use the foundations of learning from the previous lecture as a lens to provide perspective on several different forms of complex learning observed in animals.

Topic highlights:

• Complex natural examples of (possible) learning behaviors and how they relate to the basic models of learning
  • trial-and-error learning and relationship to operant learning
  • taste-aversion learning
    • similarities and differences with taste-aversion learning and imprinting and associative learning
    • identification of taste-aversion learning as having a separate neural mechanism (and empirical justifications for this idea)
  • cache retrieval
    • innate-versus-learned explanations for cache-retrieval behavior
      • Reforaging hypothesis
      • Searching-by-rule hypothesis
      • Learned cache retrieval hypothesis
    • innate-versus-learned explanations for cache-pilferage behavior
      • Foraging hypothesis
      • Searching-by-cue hypothesis
      • Observational-learning hypothesis
  • social/observational learning and pilferage
  • migration and route learning/teaching

Important terms: trial-and-error learning, taste-aversion learning, cache retrieval, social learning, observational learning, scatter hoarding, larder hoarding, reforaging, searching-by-rule, pilferage, tandem running

Lecture C1 (2024-09-12): Foundations of Learning and Memory

NOTE: UNFORTUNATELY, THE AUDIO CUTS OUT AROUND 36:45.

In this lecture, we provide foundations for discussing an important form of plasticity in animal behavior – learning. The response an animal has to its environment can be innate, or it can be modified by experience with its environment, resulting either in short-term changes (short-term learning) or long-term changes (long-term learning) with the possibility of very long-lasting changes (long-lasting learning). We discuss the different benefits and costs of these different forms of learning, which will also involve a brief description of the neural mechanisms underlying learning in animals. We then move to methods of measuring learning in behavioral experiments as well as categorizations for different forms of learning. This will allow us to introduce both non-associative learning (habituation and sensitization) and various forms of associative learning.

Topic highlights:

• the costs, benefits, and mechanisms underlying innate behavior, short-term learning, and long-term learning
  
  • protein recruitment vs protein synthesis in neurons
• "learning curve" and "forgetting curve"
• distinctions between learning, forgetting, and extinction
  • long-lasting memory, periodic reinforcement, and memory consolidation
• the basic models of learning:
  • imprinting (and critical periods)
  • non-associative learning: habituation (and repetition) and sensitization (and intensity)
    • the combination of the two as information filters
  • associative learning (conditioning)
    • operant conditioning
      • prepared, unprepared, contraprepared animals 
      • reinforcement and punishment
        • both positive and negative
    • classical conditioning
      • unconditioned/conditioned stimulus/response

Important terms: learning, forgetting, extinction, learning/forgetting/extinction curve, innate behaviors, short-term/working memory, long-term memory, long-lasting memory, periodic reinforcement, memory consolidation, stimulus, response, imprinting, habituation, sensory adaptation, sensitization, conditioning/associative learning, operant conditioning, prepared/unprepared/contraprepared, reinforcement (positive and negative), punishment (positive and negative), classical conditioning, unconditioned/conditioned stimulus/response 

Lecture B3 (2024-09-10): Quantitative Methods in Behavioral Genetics

In this lecture, we pivot from describing behavioral methods for disentangling nature (genetics) from environment (nurture) and turn toward more quantitative approaches to assessing heritability and the contribution of genes to phenotype. First, we return to the topic of "heritability" as a measure of the contribution of genetic variance to observed phenotypic variance and define two different forms of heritability – broad-sense heritability (which includes non-additive genetic effects) and narrow-sense heritability (which only includes additive genetic effects). We show how to use parent–offspring phenotypic analyses to measure narrow-sense heritability ("h squared"). As heritability will vary in a population if the corresponding trait is under selection, we then discuss how to use genetic analyses to infer whether a population is at equilibrium or currently in the process of evolving through selection or by other means. This gives us an opportunity to discuss the "Hardy–Weinberg equilibrium" and discuss some practical ways to use it. We then conclude with an introduction to QTL mapping and GWAS for understanding which combinations of genes contribute to a particular behavior (and how).

Topic highlights:

• • heritability: broad-sense and narrow-sense
  • effect of selection on heritability
  • Hardy–Weinberg equilibrium/principle
  • quantitative trait loci (QTLs) and QTL mapping
  • genome-wide association studies (GWAS, GWA studies)

Important terms: heritability, narrow-sense heritability, broad-sense heritability, Hardy–Weinberg equilibrium, quantitative traits, quantitative trait loci (QTL), QTL mapping, genetic markers, single-nucleotide polymorphisms (SNPs), linkage map, genome-wide association study (GWAS, GWA study)

Lecture B2 (2024-09-05): Methods for Disentangling Nature and Nurture

In this lecture, we continue our discussion of the combined role of genetics and the environment in the expression of a phenotype. We start by focusing on concepts from molecular genetics related to testing for the role of a single "candidate gene" using techniques like RNA knockdown. We then consider the role of epigenetics in the expression of a phenotype and discuss DNA methylation, cell differentiation, behavioral epigenetics, and genomic imprinting. Ultimately, this leads us back to seeking methodological ways to identify when a behavior has a strong genetic or environmental basis (before we look into which genes are playing the largest role). So, we introduce cross fostering, twin studies, and common gardening, which are three different ways to test whether a behavior is being determined more by the environment or by the genes.

Topic highlights:

• exploration of molecular genetics applied to the analysis of behavior
  • "candidate genes" approach and RNA knockouts and CRISPR gene editing
  • introduction of "epigenetics" ("GxExE to P")
    • brief introduction to histone modifications
    • introduction to DNA methylation 
    • discussion of role in cell differentation
    • introduction to "behavioral epigenetics" and social-insect examples analogous to cell differentiation
    • introduction to "genomic imprinting"
• exploration of common experimental methods to disentangle contribution of gene and the environment in behavior
  • definition and examples of "cross fostering"
  • definition and examples of "twin studies"
  • introduction to "common gardening"

Important terms: molecular genetics, candidate gene" RNA knockout, epigenetics, DNA methylation, behavioral epigenetics, genomic imprinting, cross fostering, twin studies, common gardening/transplant experiments

 

Lecture B1 (2024-09-03): Foundations of Behavioral Genetics

In this lecture, we cover foundational topics in modern synthesis of behavioral genetics. The lecture starts with the nature-versus-nurture debate and its historical roots in tensions between American psychologists and European ethologists (fueled in part by geopolitical contexts at the time), including a brief mention of the emergence of EO Wilson's "Sociobology" and the response to it. Ultimately, we cover the more modern, integrative, "nature-via-nurture" perspective where phenotype reflects effects of both genes (potentially many genes) and their interaction with the environment ("GxE"), and biologists are interested in understanding the relative contributes of both (e.g., with "heredity" quantifying the relative contribution of genotypic variation to phenotypic variation in a population). We then discuss different historical fields that have contributed to the modern synthesis and examples of what they have contributed. That gives us an opportunity to discuss phenomena identified in evolutionary biology that help to explain the counterintuitive observation that, for reasons unrelated to genetic drift, many traits that have an apparent fitness cost are still maintained (or at least not purged) in a population. We close looking forward to a unit on behavioral genetics that will introduce methods that behavioral ecologists use to try to separate genetic and environmental effects as well as quantitative tools for better understanding which genes contribute in complex ways to any particular phenotype/trait.

Topic highlights:

• historical nature-versus-nurture debate and contributions to its origins in ethology-vs-behaviorism
• definitions of gene, allele, genotype, character, trait, phenotype, and expression (as in "gene expression" and "phenotypic expression")
• nature-via-nurture perspective and "GxE to P" ("G by E to P" or simply "G by E")
• definition of "epistasis" and its interpretation as GxGxE
• rough definition of "heritability"
• foundations of the modern synthesis of the genotype-to-phenotype map, with focus on:
  • domestication/artificial selection
  • phylogeny (including defintion of a "cladogram")
  • quantitative and biometrical genetics
    • definition of "quantitative trait"
  • evolutionary and population genetics
    • definition of "ecotype"
    • discussion of notable evolutionary processes that maintain traits for counterintuitive reasons, including:
      • correlated characteristics
      • phylogenetic inertia
      • disruptive selection
      • the handicap principle

Important terms: G by E (GxE), G by E to P (GxE->P), GxGxE, epistasis, ecotype, gene, allele, genotype, character, trait, phenotype, expression, genotypic variance, phenotypic variance, heredity, quantitative trait, artificial selection/breeding, phylogeny, cladogram, correlated characteristics, phenotypic inertia, disruptive selection, handicap principle