Exam: Evolution Flashcards
What is evolution
Living things that change overtime according to its habitat.
What is adaption and give examples
A trait that an organism occurs that selects for their habitat trough mutations.
What is natural selection
Traits that the environment selects for to survive easier, therefore moving onto future generations,
What is artificial selection
Selective breeding to choose traits that are desired by humans.
What is sexual selection
When mating comes down to the male and female organisms, not to the environment. Chosen mainly through attractive features.
What is Lamark’s theory of inheritance of acquired traits
Traits that are developed in one’s lifetime will be passed down to the offspring
What is Darwin’s theory of natural selection
Organisms that better thrive in a environment will pass down traits that assist in survival.
What is gene flow
Net movement of alleles from one population to another (migration)
What is generic drift
Change in allele frequencies of a gene pool of a small population due to chance of events
What is the founder effect
Few individuals from a population leave and find a new island to colonize. Only a fraction of OG population is represented.
What is the bottleneck effect
Natural disasters cause drastic reduction. Like a bottle
What are the three types of natural selection and what is it.
Stabilizing= favours average phenotype in a population (baby weights)
Directional= prefers extreme or greater fitness than the average (peppered moths)
Disruptive= either extreme or low fitness than average (big fish or small fish)
What are the three types of speciation
Allopatric, sympatric, adaptive radiation
What is allopatric speciation
When population is separated by geographical barrier (river)
What is synpatric speciation
Species in same geographical area diverge and become reproductively isolsted
What is adaptive radiation
A form of allopatric speciation, diversity of common sncestricak species inri variety of differently adapted species. Species show different traust when they explore new environment, interbreeding eventually becomes impossible.
What are pre zygotes isolation mechanisms
Habitat, temporal, behavioural, mechanical, gamete
What is habitat isolating mechanism
Two species live in the same area but different habitats and rarely encounter eachother ( one living in trees and other living in water)
What is temporal isolation
Timing doesn’t match up (season, daylight)
What is mechanical isolation
Dick too big
What is gamete isolation
The sperm never meets with the egg
What are post zygotes isolation
Zygote mortality, hybrid infertility, hybrid invaibilty
What is zygote mortality
Random,t stops development of zygote,nfertilizes but never survives
What is hybrid infertility
Two species mate and hybrid is sterile but can’t make babies
What is hybrid inviability
1st gen hybrids and viable and fertile but second gen has reduced fitness
What is convergent evolution
Species that come from completely different ancestors but face similar characteristics
What is divergent evolution
When an ancestor slowly starts up evolving into different species.
What are homologous structures
Same structure but different functions
What are analogous structures
Share a common function but no common structure.
What is a vestigial structure
Structure that we used to use in the past but not anymore
