Midterm 2 Flashcards
acclimation
individ organisms experience a change in their phenotypes in response to an environmental stressor
scientific racism
use of scientific methods to justfiy hierarchical racial categories
- biological determinism: Morton associated skull traits and phys. characteristics w/ hierarchy
adaptation
when a population changes it genotype in response to environmental stressors
eugenics
selective breeding of human populations
speciation
an evolutionary process that bridges the scales of micro- and macro-evolution
- happens over periods of time and to a population NOT individ
microevolution
evolution that occurs at short timescales, usually from 1 gen to the next (i.e.) change in frequency of alleles
macroevolution
evolution that occurs over long timescales that span many gens (i.e.) dinosaurs
adaptive radiation
rapid explansion and diversification of ancestral species into new life forms and ecological niches
ecological niches
the position/role of a species w/in an ecosystem
species
set of organisms that are similar to each other and distinguished from other species by their behavior, morphology, and ability to create viable offspring
Biological Species Concept
species are a group of interbreeding organisms, connected through gene flow
- speciation occurs through reproductive isolation
Ecological Species Concept
natural selection keeps species distinct from one another bc hybrids have less fitness
allopatric speciation
process that relies on geographic isolation and a combination of reproductive isolation and natural selection
- a species is separated and split into 2 groups by a geographic barrier
parapatric speciation
no geographical barrier and partial spatial isolation
- reproductive isolation is due to behavioral or morphological traits that reduce gene flow
sympatric speciation
genetic mutation or specialization to distinct niches may allow species to diverge over time (no geographical isolation)
What are some barriers to hybridization? (8)
- geographic
- temporal incompatibility
- behavioral incompatibility
- functional incompatibility
- mate recognition
- gametic incompatibility
- hybrid sterility or inviability
- reduced hybrid fitness
phylogenetics
study of evolutionary relationships among organisms; important for understanding how our species evolve
- time is measured by evolutionary events
homology
traits shared due to a common ancestor
homoplasy
traits shared due to convergent evolution
cladistics
method for determining evolutionary relationships btwn organisms
cladogram
brancing diagram that depicts evolutionary relationships w/in a lineage
node
the point where branches split off from the main branch
outgroup
distantly related organisms that serves as a reference group to determine the evolutionary relationship btwn a set of species
ancestral traits
traits that all groups of a common ancestor possess
