Unit 6 - Evolution Vocab Flashcards
Adaptation
Inherited characteristic that increases an organisms chance of survival
Analogous Structures
Similiar structures in organisms with same purpose; no shared ancestry (ex. bird, bat, and insect wings)
Antibiotic Resistence
fast evolving ability of bacteria to be unaffected by antibiotics; caused by overuse/misuse of antibiotics
Bottleneck Effect
population’s size decreases for at least one generation causing LESS genetic variation
Directional Selection
Typeof natural selection that favors one extreme of a trait (search up graph) (ex. black feathers instead of grey and white)
Disruptive Selection
type of natural selection that favors traits at both extremes (search up graph) (ex. white and black feathers instead of grey)
Evolution
genetic change in species/populations over time making them more complex to better survive
Fossil
preserved remains of plant and animal bodies in sediment; provide evidence of evolution
Founder Effect
small group of population becomes separated from a larger population causing LESS genetic variation
Gene Flow
exchange of genes between populations due to the migration causing MORE genetic variation (migration of brown beetle to green beetle population)
Gene Pool
all the genes present in a species
Genetic Drift
Random change (typically natural disaster) causes CHANGE in genetic variation
Geographic Isolation
species becomes physically seperated and over time become different species
Homologous Structures
Similiar structures in organisms that evolved from a common ancestor with different function (ex. whale and human arms)
Mutation
change in an organisms DNA sequence caused randomly or by environment
Natural Selection
Mechanism of evolution; environment favors organisms with a specific trait; ‘survival of the fittest’
Pesticide Resistance
decreased effectiveness of insects over time to chemicals used to kill them
Phylogenetic Tree/Cladogram
a branching diagram that shows the evolutionary relationships among organisms based on characteristics
Primitive
organism that is similiar to older, less complex, organisms
Speciation
the formation of a new species from an existing species
Stabilizing Selection
Type of natural selection that favors intermediate forms of a trait (search up graph) (ex. grey feathers over black and white)
The Endosymbiotic Theory
theory of the origin of eukaryotic cells from prokaryotic organisms because of some organelles like the mitochondria
Vestigial Structure/Organ
structure that has no function but once served a purpose; explains organisms evolution (ex. finger bones of whales)
