All Things Evolution!! Flashcards
What are vestigial structures?
Reduced structures with no apparent function today
What are the two types of evolutionary change?
Anagenesis and Cladogenesis
What is anagenesis?
Micro-evolution - species will change something like colour of coat
What s cladogenesis?
Macro evolution - a whole new species
What is the definition of a biological species?
A biological species is a group of organisms that can reproduce with one another in nature and produce fertile offspring.
Why is making babies difficult?
The two organisms must be:
*Right place
*Right time
*Right behaviour
*Physically possible
*Genetically possible
What is habitat isolation?
Populations are in different habitats and so don’t meet
What is behavioural isolation?
There is little or no sexual attraction between males and females
What is temporary isolation?
Mating or flowering occurs at different seasons or different times of day
What is mechanical isolation?
There are structural differences in genitalia or flowers present copulation or pollen transfer
What is gametic isolation?
Female and male gametes fail to attract eachother or are unviable
What is reduced hybrid viability?
Where hybrid zygotes fail to develop or to reach sexual maturity
What is hybrid breakdown?
Where the offspring of hybrids have reduced viability or fertility
What is allopatry in speciation?
where species divergence happens in geographically isolated areas
What is sympathy in speciation?
Where speciation occurs in the same area
