Evolution Unit Quiz Flashcards
Neutral mutation
Mutations with neither a positive or negative effect on an organism to survive or reproduce
Harmful mutation:
A deleterious mutation that can cause disease
Beneficial mutation
Mutations that can help an organism. Ex: the ability to b amune to a certain disease
Artificial selection:
The intentional breeding to produce desirable traits
Immutable:
Not capable of change
Fossil:
Preserved evidence. Impressions and remains of organisms preserved in aged rock or mud
Paleontology:
Scientific study of previous life
Catastrophe
The theory that Geological changes in earths history were caused by catastrophes
Natural selection:
the success of certain traits with alleles passed on to generations (due to survival success in a certain environment.)
Sexual selection:
The ability to successfully reproduce by going to extreme lengths (peacocks maintain elaborate tails, elephant seals fight over territory, fruit flies dance
Convergent evolution:
When 2 unrelated species develop same traits or features
Divergent evolution:
process of tracing back 2 or more species to their common ancestor. what was once one species has diverged into two.
Adaptive radiation:
organisms that diversify rapidly into a new forms, when change in environment occurs, new resources available, new challenges, or new environmental niches are introduced
Co- evolution
When 2 or more species positively impact each other’s survival
homologous feature:
when different animals have similar bones in form or function + seem to be related.
Analogous structure:
structures in different species that have the same function but have evolved separately (do not share common ancestor) ex: wings of insects and birds used for flying.
Vestigial feature:
structure that has lost all or most of its original function in the course of evolution (ex human appendixes)
What are the paths of evolution:
- Natural selection
- Mutations
- Genetic drift
- Migration
- Nonrandom mating
2 types of natural selection:
Crossing over, independent assortment
Reproductive isolation:
when different species live in the same area, but can’t interbreed due to isolating mechanisms.
Prezygotic :
Prevents mating and fertilization
Postzygotic:
Prevents formation of fertile offspring
Prezygotic isolating mechanisms:
- Ecological: species occupy different habitats
- Temporal: species breed at different times
- Behavioral isolation: species engage in distinct courtship/mating rituals
- Mechanical isolation: interbreeding prevented by structural/molecular blockage of zygote formation.
Postzygotic isolating mechanisms:
- Hybrid inviability: abnormal zygote formation
- Hybrid sterility: (chromosomes from parents don’t crossover correctly)
- Hybrid is healthy but with later generations infertility and less fitness may show