BIO108 Final Vocab

Natural Selection

process that makes alleles more/less common

Lamarckian Evolution

evolution happens through physical changes over a lifetime

Darwinism

traits are inherited, good traits lead to more offspring and bad traits lead to less

Heterozygote protection

maintains unfavorable alleles that could be useful if the environment changes (Aa vs aa)

Neutral Variation

mutations that have no affect on phenotype

Silent mutations

no altered amino acids

Expanded Genome

development of new genes that can take on new functions (often from gene set duplications)

Mutation

change in nucleotide sequence of DNA

Crossing-over

literal swapping of the ends of DNA

Independent assortment

the way one gene is sorted does not affect the other

Random fertilization

any male gamete can fuse with any female gamete, and any male organism can mate with any female organism

Microevolution

one instance of evolution

Macroevolution

many microevolution

Camoflage

adaptation to blend in with enviroment

Mimicry

adaptation to mimic a predator/dangerous animal

Aposematism

adaptations for bright patterns to communicate toxicity/bad taste

Decent with modification

offspring will survive better than their parents

Artificial selection

selecting and breeding individuals based on desired traits

Homologous structures

Structural similarities that represent a variation from a common ancestor

Anatomical homology

similar structure for body parts

Fetal homology

similar structure invitro

Molecular homology

shared genes

Vestigial structures

remnants of an old structure

Serial homology

repetitive structures in an organism

Convergent evolution

similar structure but not common ancestor

Analogous struture

shared structure just cause it’s good

Relative fitness

the quality of an individual’s genes to another in the same species

Directional selection

one extreme is favored

Disruptive selection

two extremes are favored

Stabilizing selection

an intermediate is favored

Adaptive evolution

changes that make an organism more suited for its enviroment

Sexual selection

adaptations that help with reproduction

Sexual dimorphism

very different secondary sex characteristics for each sex

Intrasexual selection

one sex will fight members of the same sex to mate

Intersexual selection

one sex will chose who to mate with

Balancing selection

keeps unfavorable alleles in the population

Frequency-dependent selection

fitness of a phenotype depends on how common it is (too common = bad)

Altruism

a behavior that harms own fitness but helps another’s

Hamilton’s rule/inclusive fitness

a good trait helps others that are related to you without costing too much (genetic success > individual success)

Kin selection

natural selection that favors altruism

Parental altruism

resources are expended to ensure the survival of offspring

Tit-for-tat altruism

“i help you, you help me“

Genetic drift

random change of allele relative frequency over time

Bottleneck effect

a sharp reduction of population size due to random event

Founder’s effect

a new population is established by a small population of the original population

Extinction vortex

the population is so low it spirals into extinction

Genetic restoration

addition of new alleles increases

Biological species concept

species are defined by groups of population’s ability to interbreed with one another

Morphological species concept

species are defined by similar structural features

Ecological species concept

species are defined by ecological niches

Allopatric speciation

gene flow is interrupted by geological barriers

Sympatric speciation

speciation occurs in the same enviroment

Host-race formation

populations of a parasite split off depending on their host

Ploidy differences

chromosomal mutations in plants

Hybrid zone

a location with increased chances of two populations mating

Hybrid reinforcement

the offspring are less fit than the parents and pre-zygotic barriers are strengthened

Hybrid fusion

the offspring are as fit as the parents, weakening pre-zygotic barriers and fusing the two populations

Hybrid stability

offspring are as fit as the parents but pre-zygotic barriers don’t change, allowing continued formation of hybrids

Punctuated equilibria

periods of apparent evolutionary statis punctuated by change

Gradualism

organisms are constantly slowly evolving

Pre-zygotic barriers

reproduction barriers before conception

Habitat isolation

geography keep populations from mating

Temporal isolation

different reproduction windows keep populations from mating

Behavioral isolation

different mating rituals/communication keep populations from mating

Mechanical isolation

different morphological structures keep populations from mating

Gamete isolation

different sperm/egg keep population from mating

Post-zygotic barriers

reproductive barriers after birth/during development

Hybrid viability

dies in development/after birth

Hybrid fertility

unable to reproduce

Hybrid breakdown

F1 offspring are viable/fertile, but F2 offspring are not

Phylogeny

the evolutionary history of a species

Linnaeus’s system

based on resemblances of organisms

Binomial naming system

Genus + Species

Phylogenic tree

model to show organism history

Taxon

Each DKPCOFGS

Sister taxon

an intermediate common ancestor

Cladistics

groups organized by common ancestry

Clades/Monophyletic groups

a common ancestor + all decendants

Paraphyletic group

a common ancestor + some decendants

Polyphyletic group

a bunch of organisms, not all with the same common ancestor

Shared ancestral character

a common trait held by a polyphyletic group

Shared derived trait

an evolutionary novelty unique to a clade

Maximum parisomy

the simplest answer that is consistent with fact is best

Maximum likelihood

probability rules about how DNA changes

Evolutionary Development (Evo-Devo)

compares developmental processes of organisms

Homeotic genes

determines the identity of body structures

Homeobox genes

a 180 nucleotide sequence that has been conserved

FOXP2 gene

required for proper language development

Gene families

repeated gene duplications

Orthologous genes

homology found across different species

Paralogous genes

from gene duplication and can be found in multiple genomes

Three domain system

Eukaria, Prokaria, Archae

Horizontal/Lateral gene transfer

the movement of genes between organisms

Gene flow

movement of genes across populations

Outgroups

a group of distantly related organisms that branched off from the taxa before branching off within itself

Behavioral ecology

the study of animal behavior based on evolutionary pressures

Parental care

when parents actively rear their offspring

Molecular clock

using the constant rate of evolution in genes to determine the rate of evolution