Genetic diversity and adaptation

All the organisms of a particular species that live in the same place

• Different forms of a particular gene, found at the same locus (position) on a chromosome • A single gene could have many alleles

The total number of different alleles in a population

Ability to adapt to a change in environment; allows natural selection to occur

• Random mutations result in new alleles • Some alleles provide an advantage, making an individual more likely to survive and reproduce • Their offspring receive the new allele, and frequency continues to increase over many generations

• Occurs when environmental conditions change • Individuals with phenotypes suited to the new conditions will survive and pass on their genes • Over time the mean of the population will move towards these characteristics

• Antibiotic resistance • Bacteria with a mutation allowing them to survive in the presence of antibiotics will reproduce • Frequency of this allele will increase and the population will shift to have greater antibiotic resistance

• Occurs when environmental conditions stay the same • Individuals closest to the mean are favoured, and any new characteristics are selected against • Results in low diversity

• Birth weight: babies that weigh around 3 kg are more likely to survive than those at lower/higher weights

• The role of a species within its environment - Species sharing the same niche will compete with each other

• Anatomical (changes to body structure) e.g. oily fur • Physiological (changes to bodily processes) e.g. venom production • Behavioural (changes to actions) e.g. hibernation