Chapter 2 Evolution of Behavior Artificial Selection Natural

Chapter 2: Evolution of Behavior • Artificial Selection • Natural Selection • Sociobiology, Selfish Genes, and Adaptation • Phylogeny and the Study of Animal Behavior

Natural Selection produces an incredible array of traits! Sequential hermaphroditism occurs in many fish and gastropods Individual sex at some point in its life. It can change from a male to female (protandry), or from female to male (protogyny) Ocellaris Clownfish (Amphiprion ocellaris), a protandrous fish species Moon Wrasse(Thalassoma lunare), a protogynous fish species

Parthenogenesis usually results in an all female species The Indo-Pacific Gecko (Hemidactylus garnotii) is a parthenogenetic species

Artificial Selection Charles Darwin studied domesticated pigeons Darwin (1868) The Variation of Animals and Plants Under Domestication Selection for morphological variation

Artificial Selection for behavioral variation in pigeons (top: tumbling bottom: homing)

Artificial Selection for behavioral variation in domestic dogs Herding behavior

Natural Selection Selective Advantage of a Trait Group Hunting in Cape Hunting Dogs (Lycaon pictus)

Natural Selection Selective Advantage of a Trait 1. Group Hunting in Cape Hunting Dogs Phenotype Genotype Allele Fitness advantage

Darwinian fitness or overall fitness describes how successful an organism has been at passing on its genes. The more likely that an individual is able to survive and live longer to reproduce, the higher is the fitness of that individual. Absolute Fitness The total number of gene copies transmitted to the subsequent generation or the total number of surviving offspring that an individual produces during its lifetime. Relative Fitness A measure of biological fitness expressed as the ratio of the absolute fitness of an individual (or of a genotype or of a phenotype) and the absolute fitness of a reference individual (or of genotype or of phenotype). Inclusive fitness The number of genes individual organism to passes to the next generation, including the shared genes passed on by the organism's close relatives.

Natural Selection How Natural Selection Operates

Natural Selection How Natural Selection Operates Parent-Offspring Regression Cliff Swallow group size

Sociobiology, Selfish Genes, and Adaptation Fluctuating Asymmetry Selection for symmetrical males?

Sociobiology, Selfish Genes, and Adaptation

Killifish, Rivulus hartii, are small, fairly innocuous predators that can eat only tiny guppies. Are found in upstream (lowpredation) sites in the rivers of Trinidad Pike cichlid, Crenicichla alta is large a predator common in downstream sites native to guppies.

Sociobiology, Selfish Genes, and Adaptation Kinship and Naked Mole Rat Behavior EUSOCIALITY

Sociobiology, Selfish Genes, and Adaptation Human Mate Choice (Buss, Trivers, Zahavi) Parental Investment Female Choice Handicap Principal

Phylogeny and the Study of Animal Behavior