evolution Flashcards
evolution
change in species over time
theory of natural selection
survival of the fittest on a larger scale
- charles darwin’s explanation on how evolution happens
adaptaion
change in the characteristics of individuals in a population
- allows them to cope with long term environmental changes
variation
- result from mutation or genetic recombination
overproduction
individuals produce more offspring than available resources
struggle for existence
resources are in limited = organisms have to compete for resources
survival of the fittest
competition between two individual organisms
heredity
passing on their genes to their offspring
environmental change
drastic change in environment
- individuals with adaptive characters will survive. those that are not will migrate or perish
genetic change
gene mutations produce new traits
directional selection
one phenotype that gives adaptive advantage is favored over another
genetic drift
by chance
structural adaptation
part of the body
behavioral adaptation
behavior/actions (ex: hibernation)
evidences of evolution
- evidence from fossil record
- evidence from variation (existence of different varities within a species)
- evidence from mutation (source of new traits):
spontaneous: random, and at nature
induced: deliberately affected by people - evidence from similarities in developmental changes (changes in body structure)
- similarities in structure (similar structure have close evolutionary ties) (similar creatures are because of common ancestry (homologous structures))
- evidence from molecular biology (dna) (comparative embryology: how creatures develop)
