Second Exam: Thursday 29 October 2015 Covers Chapters 5, 8, 9,10, and 11 Lectures 10 to 19 plus Agriculture Global Warming The Vanishing Book of Life on Earth Plastics Intelligent Design? The Weakest Link Technology Economics Lecture # October 2015

Social Behavior Hermits must have lower fitness than social individuals Clumped, random, or dispersed (variance/mean ratio) mobility = motility = vagility (sedentary sessile organisms) Fluid versus Viscous Populations Use of Space, Philopatry Individual Distance, Daily Movements Home Range Territoriality (economic defendability) Resource in short supply Feeding Territories Nesting Territories Mating Territories

Sexual Reproduction Monoecious (Hermaphrodites) versus Diecious Evolution of Sex —> Anisogamy Diploidy as a “fail-safe” mechanism Costs of Sexual Reproduction (halves heritability!) Facultative Sexuality (Cladocera, Daphnia) Protandry Protogyny (Social control) Parthenogenesis (unisexual species) Possible advantages of sexual reproduction include: two parents can raise twice as many progeny mix genes with desirable genes (enhances fitness) reduced sibling competition heterozygosity biparental origin of many unisexual species

Male Peacock, a victim of female mating preference

Runaway Sexual Selection (Fisher) Handicap Hypothesis (Zahavi) Sensory Exploitation Hypothesis (Ryan) Leks Alternative mating tactics, Cuckoldry Satellite males Internal versus External Fertilization Ecological Sexual Dimorphisms Bower birds Ratites Bushland tinamou

Sage Grouse Lek

Sage Grouse Female

Male Reproductive Succes in Sage Grouse

Geographic Range of Sage Grouse

Prairie Chicken

Atwater Prairie Chicken

Jacana, Lily pad walker

Dinosaur fossils suggest that male parental care could be ancestral in birds If so, ratites could have retained the ancestral state And, if so, then female care and biparental care would be derived conditions A male of the medium-sized predatory dinosaur Troodon (North America late Cretaceous) brooding a large clutch of eggs. Female archosaurs extract substantial amounts of calcium and phosphorus from their skeletal tissues during egg formation. Histologic examination of cross sections of bones (femur, tibia, and a metatarsal bone) from an adult Troodon found in direct contact with an egg clutch revealed little evidence of bone remodeling or bone resorption, suggesting that the bones were those of a male. Fossilized remains of Troodon and two other types of dinosaurs found with large clutches of eggs suggest that males, and not females, protected and incubated eggs laid by perhaps several females (Credit: Bill Parsons)

Red-eyed Vireo

Four Possible Situations Involving an Individual ’ s Behavior and Its Influence on a Neighbor __________________________________________________________________ Neighbor(s) Gain Neighbor(s) Lose __________________________________________________________________ Individual GainsPseudo-altruistic behavior Selfish behavior (kin selection) (selected for) __________________________________________________________________ Individual Loses True altruistic behavior Mutually disadvanta- (counterselected) geous behavior (counterselected) _________________________________________________________________

W. D. Hamilton (1964) Kin Selection Inclusive Fitness Hamilton ’ s rule: r n b – c > 0 r = coefficient of relatedness n = number of relatives that benefit b = benefit received by each recipient c = cost suffered by donor r n b > c “ Adaptive Geometry of a Selfish Herd ”

“ Adaptive Geometry of a Selfish Herd ”

Eusocial Insects Hymenoptera ( “ thin wings ” ) Ants, bees, wasps, hornets Workers are all females Haplodiploidly Isoptera ( “ same wings ” ) Termites (castes consist of both sexes) Endosymbionts Parental manipulation Cyclic inbreeding

White-Fronted Bee Eaters, Kenya

Helpers at the Nest in White-Fronted Bee Eaters in Kenya __________________________________________________________________ Breedersr* Number of Cases % Cases __________________________________________________________________ Father x Mother Father x Stepmother Mother x Stepfather Son x Nonrelative Brother x Nonrelative Grandfather x Grandmother Half brother x Nonrelative Uncle x Nonrelative Grandmother x Nonrelative Grandson x Nonrelative Great grandfather x Nonrelative Nonrelative x Nonrelative Total __________________________________________________________________ * r = coefficient of relatedness.

––-> <---- Donor Recipient Small costs, large gains, reciprocated Sentinels Robert Trivers Biological basis for our sense of justice? Friendship, gratitude, sympathy, loyalty, betrayal, guilt, dislike, revenge, trust, suspicion, dishonesty, hypocrisy Reciprocal Altruism (Trivers 1971)

Selfish caller Hypotheses 1. Full up “ I see you ” 2. Mass pandemonium 3. Keep on moving 4. Mixed species flocks, fake alarm calls