Lecture 11 - Chapter 51 - Behavioral and Social Evolution

Lecture 11 - Chapter 51 - Behavioral and Social Evolution -...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Behavioral Evolution What an animal does and how it does it Includes muscular and nonmuscular activity Chapter 51 2 Proximate and Ultimate Questions • Proximate, or “how,” questions about behavior – Focus on the environmental stimuli that trigger a behavior – Focus on the genetic, physiological, and anatomical mechanisms underlying a behavioral act • Ultimate, or “why,” questions about behavior – Address the evolutionary significance of a behavior 3 Schooling in fish • How? Sense movement of other fish by sight (eyes of sides of head) and lateral line • Why? Minimize predation, reduce friction 4 Ethology • The study of behavior, especially under natural conditions • Discipline developed in mid-1900s (Tinbergen, von Frisch, Lorenz)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
5 Fixed Action Patterns Sequence of unlearned behaviors that are largely unchangeable Usually carried to completion once initiated Triggered by external stimuli 6 • In male stickleback fish, the red underside of an intruder stimulates an attack (a) A male three-spined stickleback fish shows its red underside. 7 • When presented with unrealistic models – As long as some red is present, the attack behavior occurs Figure 51.3b (b) The realistic model at the top, without a red underside, produc The realistic model at the top, without a red underside, produc es no es no aggressive response in a male three -spined spined stickleback fish. The stickleback fish. The other models, with red undersides, produce strong responses. other models, with red undersides, produce strong responses. 8 When dominant female dies her male mate changes sex and replaces her
Background image of page 2
9 Imprinting • Includes both learning and innate components • Generally irreversible • Develops only during critical period Fig 51.5 (link) 10 (Hyperlink tool use) 11 Adaptive significance of various behaviors • Inflexible behavior adaptive when mistakes would be costly • Innate behavior advantageous when learning opportunities are limited 12 Rats are particularly good at learning navigation Learning: Domestic dog breeds have exaptations for different types of learning Most behaviors influenced by both genes and environment
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/03/2009 for the course BISC 120 at USC.

Page1 / 12

Lecture 11 - Chapter 51 - Behavioral and Social Evolution -...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online