evolution chapter 8 terms: Flashcards
evolution
process of genetic change in population over time
paleontology
study of ancient life
catastrophism
destroyed species living in a region
uniformitarianism
geological processes operated at the same rates in the past as they do today
inheritance of acquired characteristics
characteristics acquired during an organisms life can be passed on to its offspring
theory of evolution by natural selection
- how life changed and continues to change
individuals with traits that helped them survive in their environments are more likely to survive and pass on traits
descent with modification
- theory that natural selection doesn’t demonstrate progress
- based on species’ ability to survive environment conditions at certain times
fossil records
shows organisms alive in the past
ex: where they lived, when they became extinct, order they appear in history
transitional fossils
intermediary links between groups of organisms, share characteristics, provides evidence that they are related
vestigial structure
reduced version of a structure that WAS functional in organisms ancestors, may be present but doesn’t function
ex: whale’s pelvic bone
biogeography
supports hypothesis that species evolve in one location and spread out to other places
homologous structure
similar structure but different functions
ex: vertebrate forelimbs
analogous structure
similar function but different structure
ex: birds and bats
embryology
study of early, pre-birth stages of organisms development
ex: paired pouches- vertebrate embryos have paired pouches of throat
5 sources of evidence for evolution
- fossils
- biogeography
- anatomy
- embryology
- dna
evidence from fossils
remains and traces of past (animals, plants, etc.) that give scientists record of past life
ex: fossil records show where they lived
evidence from biogeography
study of past and present geographical distribution of species population
ex: darwins evidence- birds on galapagos islands resembled those of mainland south america
- suggested island species evolved from those that migrated from mainland
evidence from anatomy
as vertebrates evolved, same bones put to different uses
ex: birds and bats -> flying
horses and dogs -> running
whales and seals -> swimming
evidence from embryology
embryos of different organisms exhibit similar stages of embryonic development
ex: fish -> pouches develop into gills
evidence from dna
evolutionary relationships between species related in their dna
ex: dogs related to bears
whales and dolphins related to ungulates (hoofed animals- cows)
