Speciation and individual variation Flashcards
(12 cards)
What is the definition of speciation?
The process of a species becoming another species
What is Allopatric speciation?
Speciation arising from geographical separation
What is Sympatric speciation?
arising from variation in fertilisation or courtship behaviour
How does reproductive isolation cause speciation?
isolation causes 2 populations with separate gene pools each with their own genetic variation and mutations.
Overtime the change in allele frequency is so vast is causes 2 new species
In terms of natural selection what is stabilising selection?
The favouring of the intermediate phenotype.
E.g Goldie locks porridge
In terms of natural selection what is directional; selection?
The favouring of extreme phenotypes E.g Antibiotic resistance
What is genetic drift?
A change in allele frequency by chance E.g a group of bugs getting stepped on
Alleles can just dissapear
Has the greatest affect on smaller populations
What is genetic bottle neck?
A type of genetic drift
When a size of population drastically decreasses
E.g forest fire
What is the founder affect?
When individuals in a large population break off and from a new population
What is artificial selection?
When farmers selectivly breed Plants or Animals with desirable characteristics
Please explain the process of artificial selection
Select male and female w desirable characteristic
Do the same for the offspring
Rinse and repeate
What are 3 problems with artificial selection/selective breeding?
Decreases gene pool
Decreases genetic variation
Increase health risks
