IB Biology A4.1 Definitions
This page contains our IB Biology definitions for A4.1. By learning each one of these definitions, you will fully cover the content for IB Biology 'Further speciation'.
behavioural isolation
Reproductive isolation due to populations of the same species behaving differently in a way that prevents interbeeding, such as having different mating calls or rituals
geographical isolation
Reproductive isolation due to populations of the same species living in different areas. This can be as extreme as different continents to as close as different parts of a tree
gradualism
The gradual separation with changes over time building up to form a new species
polyploidy
An error in meiosis leading to a doubling of chromosomes
reproductive isolation
When populations of the same species stop interbreeding, a requirement for speciation
speciation
The formation of a new species as a result of evolution
temporal isolation
Reproductive isolation due to populations of the same species breeding at different times, and so they do not interbreed at all
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