Biodiversity & Evolution Flashcards
what are the 2 forms of genetic drift?
Bottleneck effect : occurs when a population undergoes a catastrophic event
founder effect: occurs when a small group of individuals establishes a new population in a new area geographically isolated from the original population.
homologous vs analogous
Homo:
. shares common ancestor
. may have different functions
. divergent evolution
Ana:
. does not have common ancestor
. similar function purpose
. convergent evolution
what is a phylogenetic tree?
A diagram that represents the evolutionary pathways and relativeness between species
Darwin’s finches
when Darwin visited the Galapagos islands, he discovered a diverse array of finches on different islands but all finches exhibited different variations of beak size and shape.
The various big sizes came from natural selection: individual birds with beaks better for obtaining food had high chance of survival and reproduction
What are the 3 types of Biodiversity
Species
Genetic
Ecosystem
What is Species Diversity?
variety and abundance
What is Genetic Diversity?
range of different inherited traits within a species
What is Ecosystem Diversity?
A variety of ecosystems and habitats present in a given area or on a larger scale
3 types of Evolution
Divergent
Convergent
Co-Evolution
Define Divergent Evolution
different organisms that have common ancestors develop different traits or characteristics to adapt to the changing environmental conditions and selection pressures
Define Convergent Evolution
when organisms that aren’t closely related evolve similar features or behaviours, in response to similar selection pressures.
Define Co-Evolution
two species evolve together due to their close relationship
4 factors that influence genetic diversity
Mutation
Gene Flow
Genetic Drift
Natural Selection
Define Mutation
Changes that occur in an organisms DNA. can be advantageous or disadvantageous.
Define Gene Flow
when individuals migrate from one population to another and interbreed with individuals from another population. INCREASES GENETIC DIVERSITY.