3.1.3—Biodiversity from evolution

Syllabus
First assessment 2026
Objective
3.1.3
Level
SL

Place Evolution at the Population Scale

Evolution is inherited change in a population across generations, not an adjustment made by one individual during its lifetime.

Acclimatization can change an individual without changing inherited frequencies. Evolution is detected when descendants inherit a different trait or allele distribution.

A person tans in sunlight without evolving; a population becoming more UV-tolerant over generations may reflect evolution.

A heritable frequency shift between generations, not a short-term physiological response.

Individuals do not evolve to meet a need; populations change through inherited variation and selection.