IB 105 – Lecture 5

biotic
living portions of the environment

take part in predation, parasitism, competition, etc.

abiotic
nonliving factors

ex: rain, soil, temperature, etc.

evolution
change over time in gene/allele frequencies within a population

process by which characteristics change over generations

natural selection
the process that determines which individuals within a species will reproduce and pass their genes to the next generation
examples of evolution in action
pepper moths

fish

bacteria

mechanisms of evolution
natural selection
mutation
genetic drift
migration
sexual selection
coevolution
When two or more species interact closely they can influence each other’s evolutionary direction.

Evolutionary change in one species will lead to evolutionary change in other or the second species may go extinct.