1 Framework

• Kin selection

• Proximate / causal

  • Causation/ mechanism: length of day triggers change in hormones, the way air flows through the throat

  • Developmental/ Ontogeny: learned songs from parents

• Ultimate/ functiona

  • Adaptive advantage/ function: communication (e.g. to attract mate)

  • Evolutionary history/ phylogeny: evolved from ancestors that have been doing the same.

The more the genetic frequency of one type is increasing, the more likely it is for the other type to increase.

Hybridisation experiment of the migratory birds.

A trade-off exists when one trait cannot increase without a decrease in another trait.

Ability of a single genotype to alter its phenotype in responses environmental conditions.

Relative contribution of an individual to the gene pool of the next generation.

(Foraging, avoiding predators, finding mates, raising offspring)