Home > Subjects > Biology > Level 3 > 3.5 Patterns of evolution > Subject content
- Subject: Biology
- AS: AS90717
- Level: 3
- Credits: 3
- External
Biology 3.5 Describe processes and patterns of evolution
Subject content
Make sure you have up-to-date course notes. Use them, and if you haven't got them, see your teacher. The topics you may be tested on will include the following:
- Processes of evolution:
- ways in which speciation occurs:
- sympatric
- allopatric
- reproductive isolating mechanisms that contribute to speciation:
- geographical
- temporal
- ecological
- behavioural
- structural barriers
- polyploidy
- the role of natural selection.
Many of New Zealand’s unique terrestrial species have evolved by allopatric speciation. New Zealand is an isolated country, having become separated from other continents by continental drift. Earth Like a Puzzle shows how an ancestral species become isolated. Rising sea levels have also caused isolation at various points in New Zealand’s geological history.
See a selection of New Zealand examples of evolution.
- ways in which speciation occurs:
- Patterns of evolution:
- convergent evolution
- divergent evolution (includes adaptive radiation which occurs when more than one species arises from a common ancestor
- coevolution, which is the phenomenon where two taxa evolve together. Check out evidence of coevolution amongst birds. Also, link to this tutorial on coevolution and find further examples.
- punctuated equilibrium
- gradualism.
Check this web page that explains competing hypotheses about the pace of evolution.
