Things to know for describing evolution

Within-population heritable variation

Organisms within a population vary in their heritable traits

Struggle for resources / Selecting force

Populations produce more offspring than the environment can support

Differential survival and reproduction

Individuals with heritable traits that make them better suited to the local environment survive longer and produce more offspring than others.

Accumulation of favourable traits

Over generations

Populations are the units of evolution

Evolution acts on populations

Environment as the driving force

The environment determines which heritable traits are favourable

Dependence on heritable traits

Natural selection relies on heritable traits