| Genetic diversity | measured by the number of different alleles in a population |
| Gene pool | a gene pool is a collection of all the different alleles of a gene in pop species |
| Causes of variation | - Gene mutation- sudden changes to genes/chromosomes
- Meiosis- new combinations
- Random fertilisation-
- Environmental factors |
| Beneficial adaptation | increase the chance of survival
Behavioural - playing dead, dancing before mating
Physiological - bears hibernating
Anatomical - shape , layer of skin |
| Types of natural selection | Directional selection - one extreme characteristic in environmental
Stabilising selection - middle range of characteristics due no change in environmental conditions
Disruptive selection - two extreme characteristics |
| Mnenomic to describe the process | very awesome crabs seek raunchy females tonight
variation alleles change survive reproduce frequency type of selection |
| Process of natural selection | A pop has gv due to mutations
Different alleles - produce new alleles that not all individuals will have favourable alleles
a change in environment or no change
survive or die depending on favourable alleles
survivors with fave will reproduce passing on these genes
the allele freq for the favourable al increases
dir ses or stab ses or dis ses |
