Lecture 8

Units of evolution

A hierarchy of selection

G = GenerateT = TestR = Regenerate★= Locus of selection

“GTR” is a way of characterising a selection process, by Henry Plotkin

Selection

Selection is a feedback cycle that passes variants through a “fitness filter”.

Many and the Many

Individuals 1

Individuals 2

Individuals 3

Individuals 4

Populations and selection

Disruptive selection occurs when a curve becomes bimodal and adjusts to more than one fitness peak.

Adaptive zones

Lineages

Hennig’s view

Historical trees and cladograms

Cladistic terms

The Dual Hierarchy, revised

Weismannian inheritance

Lamarckian evolution