Evolution Flashcards
Lamarcks theory
1) tendency toward perfection
2) use and disuse
3) inheritance of acquired traits
Evolution
Process where modern organisms descended from ancient ones
Artificial selection
Not rlly evolution (unnatural), intentional breeding; can be a model for how evolution may operate
Natural selection
Occurs through random mutations where traits become more or less common in a population due to consistent effects upon survival/reproduction of their bearers
Driving factor that indicates survival
Environment; acts as a sieve, some variations pass others don’t
Darwin’s observations
1) individuals with a species can vary
2) some variability is inherited
3) every generation produces far more offspring than can survive and pass on variations
4) populations of species tend to remain stable in size
Adaptation is a choice (T/F)
F: based on random mutations
Adaptation
A structure, behaviour, or physiological process that helps an organism survive and reproduce in a particular environment
Mimicry
To appear as something you’re not
Adaptations are _____
Gradual changes that accumulate in the DNA after many generations (NOT EVERY VARIATION IS PASSED ON)
Anatomy
- homologous structures but diff functions (humans and cats have digits but use them differentially)
- analogous, similar functions but different origins (mosquitoes and birds have wings but aren’t related)
- vestigial: structures from ancestors that aren’t useful (tailbone and appendix)
Fossils
Transitional fossils
- contain vestigial structures
- tech can date them with c dating
Embryology
- similar stages of embryonic development
- must have a common ancestor if we evolve similarly
DNA
Determine how closely related two organisms are by comparison: traits passed on through generations and changed by mutations
Biogeography
- mutations in dna can caused diff in organisms
- expansion of parts of lands separates species and organisms who now grow in diff climates and environments
