BIOLA 208

Biological Anthropology

Falsifiability

can be tested and proven to be untrue

Replicability

someone can repeat a study and get the same results

Parsimony/Occam’s Razor

the simplest explanation with the fewest assumptions is the best explanation

List Nikolas Tinbergen’s 4 levels of explanation and their definitions

Mechanism/causation - how trait/behavior works

Ontogeny - how trait develops over organism’s lifetime

Phylogeny - how it evolves across generations

Function - why trait exists for survival and environment

Criteria for determining which scientific explanations to believe

Falsifiability, replicability, and parsimony,

Identify the following for Proximate & Ultimate explanation:
Which levels of explanation:
Timeframe:

Characteristics:

proximate: mechanism & ontogeny, during organism’s lifetime, anatomical/physiological/developmental

ultimate: phylogeny & function, across generations, functional/historical

How do we test Ultimate Explanations?

Correlation, causation, experiment manipulation, cross species comparison

correlation definition

2 things move together

causation definition

one thing makes the other happen

experimental manipulation definition

superior line of defense, intentionally changes the independent variable to see the effect on the dependent variable

cross species comparison definition

comparing data across different organisms to identify conservation and divergence

convergent evolution definition

development of similar physical traits in unrelated species that face matching environmental pressures

naturalistic fallacy definition

the mistake of assuming something is good or right just because it happens to occur in nature

allele definition

alternative versions of a gene

heritability equation an definition

h², proportion of phenotypic variation among individuals due to genetic differences

what are the causes of evolution and their definitions?

mutation

gene flow - transfer of genetic material from one population to another

genetic drift - random changes across generations

natural selection - when organisms with helpful, inheritable traits survive and reproduce more successfully than others in the environment

artificial selection definition

certain individuals with desirable traits reproducing

what are the prerequisites for evolution by natural selection?

variation, heritability, differential reproduction

what factors control the rate of evolution by natural selection/

strength of association between variation and reproductive differences, heritability, generation time

why do organisms produce?

because only those organisms have descendants in the world today, favors reproductive success

what are the constraints on “perfection”

cost

variation/historical constraint

non-adaptive evolution/genetic drift

generation time

facultative trait definition

a response to an environmental change, low heritability

obligate trait definition

required, inflexible traits essential survival

altruism definition

any behavior that s reproductively advantageous to the recipient, but costly to the donator

costs of sexual reproduction:

time, energy, male attraction, competition, vulnerability, disease risk

what are the two types of hermaphrodtism

simultaneous, sequential

list the two types of sequential hermaphroditism and their definitions:

protogynous - begin as female and transition to male

protandrous - begin as male and transition to female

simultaneous hermaphrodism definition

male and female at the same time

what is meiosis and its cost?

cell division in sexually reproducing organisms, one diploid cell turns into 4 haploid gametes

cost - organism only passes ½ of genes

what is recombination and its cost?

DNA is broken and recombined to make new combinations of alleles

cost - disrupts sexual combinations of genes, creating new genotype that might perform poorly

male gamete traits:

female gamete traits:

males have small, motile sperm

females have large, non-motile eggs

what is the adaptation hypothesis?

organisms adjust their structure or behavior in response to environmental changes, stressors, or internal demands in order to maintain stability

hermaphrodite definition

an organism that has both female and male reproductive organs

intersexual selection defintion

“between”, one sex chooses mates based on attractive traits

intrasexual selection defiition

“within”, members of one sex compete directly with each other

what is Bateman’s principle

greater variation in reproductive success among males than females

operational sex ratio (OSR) definition

ratio of sexually active, reproductively available males to females; influenced by parental care duration, recovery time after mating, how quickly each sex can reproduce, offspring mortality