ESGA Exam 1 Study Guide

Our model of the universe

Our minds contain a model of the universe; our experience (ex. vision) is allowed to update it, but only in certain ways; we often overlook what we don’t expect to see

Gender Schema

Stereotypes of what gender may imply; overestimating height/skill level of men/boys and the inverse for women/girls; same behavior in young girls may be rated more aggressive than in boys

Apophenia

universal human tendency to seek patterns in random information, like gambling

Anthropomorphization

Ascribing human characteristics to things that are not human; attributing conscious thought to animals too quickly, like Clever Hans

Scala Naturae

Fix this after lecture

Naturalistic Fallacy

Fix this after lecture

Human Ancestry as a Cognitive Bias

If scientists are expecting a certain outcome, they will try to make the evidence in hand come to that conclusion; fracture in skull of early human skull was thought to be from other human-adjacent species but was really from crocodile

Cultural Bias

Different cultures seeing the primarily eyes/mouths in emoticons

Gender Bias in History (Darwin, Aristotle)

In their societies, women were seen as the inherently “weaker” sex; chauvinist view led to findings being male-centric

Gender Bias in Recent History

Pinyon Jays: viewed as pacifists; scientists tried to induce fighting, and with an absence of conflict, were forced to focus on subtle interactions between them; they did not find a conclusive “dominance matrix”: however, scientists DID record direct aggression between the species, but not in their discussion of hierarchies. They viewed female aggression, but attributed it to “PBS” (“pre-breeding syndrome”)

Gorillas: need to ask about this

Spotted Sandpipers: females could carry sperm, and showed aggression; early scientists assumed and applied traditional gender roles onto the birds, before realizing that the males were nest tenders and the females could carry sperm

Scientific Method

1. Observe

2. Question

3. Hypothesize

4. Experiment

5. Interpret

Diversity of Perspective

Can help alleviate blindspots of other scientists whose life experience may have led them not to consider something

Evolution

Any change in allele frequencies in a population over time

Population

A localized group of organisms which belong to the same species

Allele

A variant of a gene

Gene

The basic physical and functional unit of heredity (strands of DNA that include instructions for proteins)

Chromosomes

Thread-like structures located inside the nucleus containing the DNA

Natural Selection

The differential success in reproduction of variants in a population; a mechanism of evolution

Evolutionary Fitness

The relative contribution an individual makes to the next generation via genetics; the currency of natural selection

Species

A group of actually or potentially interbreeding populations which was reproductively isolated from other such groups

Genetic Drift

Changes in allele frequencies due to chance; a mechanism of evolution

Mutation

Mistakes in gametes that may create new alleles; if new allele increases fitness it will become more common

Phenotype

Set of observable characteristics of an individual resulting from the interaction of its genotype with the environment

Genotype

A set of genes in DNA responsible for unique traits or characteristics

Unit of Evolution

Population

Unit of Natural Selection

Individuals

Example of genetic divergence

Ancestral giraffes spread around African continent, barriers formed leading to isolation, and changes occured through chance/selection

Example of speciation

Reproductive isolation; when those giraffes evolutionally diverged, different traits emerged and then dissuaded the different species of giraffe from intermingling with eachother (smell, looks, etc)

Dr. Russell’s Top Ten Things to Understand About Evolution

1. The Significance of chance; change is the default

2. History is important; every species has evolutionary history/baggage

3. everything changes; variation/flexibility are good bc environments change

4. “use it or lose it”; it takes energy to maintain structures

5. It’s all about the genes; nat sel will not cause trait to be more common onless those who have it leave more offspring than those who don’t

6. Everything is both “nature” and “nurture”; even genes have to be activated to be expressed before they produce a trait

7. It’s all relative; traits just need to be relatively better than the alternatives

8. every innovation began as a mistake; there is no plan

9. Humans are like any other life form; we have unique history, evolve, and share common ancestors

10. Humans are NOT like any other life form; culture, self-awareness, anticipation of consequences, medicine

Examples of “recent” human evolution

• Lactose tolerance increased

• Increase in blue eyes/blonde hair/light skin

• Increase in Type 1 Diabetes

• Decreasing sucseptibility to HIV

• Sickle Cell

• Decrease in wisdom teeth

• High altitude breathing in certain areas

Behavior

All observable or otherwise measurable muscular or secretory responses (or lack thereof) in response to changes in an animals internal or external environment

Examples of behavioral traits

• food preferences

• foraging behavior (how far to go)

• level of fearfulness

• level of aggression

• favoring particular colors or sounds of potential males

• Risks to self vs. risks to offspring

Does behavior have a genetic basis?

Yes

Behavior vs. Morphology

Morphology is more black and white, and more conservative; behavior sees more individual variance, evolves quicker

How do we use the Comparative Method?

Using comparisons across species that have evolved independently as a way to understand the evolution of behavioral traits

Why is the comparative method used?

To see whether two species share traits because they share an evolutionary history OR because they share/have shared a common selection environment

The Comparative Method

A tool that allows us to answer evolutionary questions about behavior; how behavior evolved due to natural selection, and WHY animals do what they do

Divergence/Divergent Evolution

Closely related species exhibit different behaviors

Convergence/Convergent Evolution

Unrelated species exhibit similar behaviors

Phylogenies

Maps to observe divergence/convergence in evolutionary trees

Shorebirds

females compete for and court multiple male mates, males handle all incubation and child-raising duties; scientists went back in evolutionary history to observe where that trait may have genetically originated from

Brains/Plasticity

Brains change due to environment/experience

Non-Adaptive Traits

Not all traits (whether morphology or behavior) are adaptive; they are not all heritable, not independent, selection pressures change, and there’s other evolutionary forces like chance and history

Panda Principle

evolution leaders to creatures that are “good enough” for their environment rather than perfect; pandas have a clumsy thumb made from an elongated wrist bone

Evolutionary Baggage

traits inherited from ancestors that were useful it the past, but are now suboptimal or useless; tailbone, appendix, wisdom teeth, goosebumps

Evolutionary Psychology/Human Behavioral Ecology

Applying principles of adaptive evolution to human behavior attempting to understand what we do; leads to testable hypotheses