1. 10. Cooperation and Helping

2. Inclusive Fitness Direct Fitness (Individual Fitness): personal reproductive success measured as the number of offspring that survive and reproduce Indirect Fitness: reproductive success of individuals that share genes with the donor Inclusive Fitness = Direct Fitness + Indirect fitness: the total genetic contribution of an individual to the next generation

3. Coefficient of relatedness Coefficient of relatedness ( r): proportion of alleles shared between two individuals as a result of common descent (ancestry) RelationshipAverage r coefficient Parent-offspring0.5 (1/2) Full siblings0.5 (1/2) Half siblings0.25 (1/4) Grandparent-Grandchild0.25 (1/4) Aunt or uncle - niece or nephew0.25 (1/4) First cousins0.125 (1/8)

4. Mitosis Meiosis

5. Parents gametes (1n) How are traits transferred to offspring? Offspring gametes (1n)

7. Calculating Inclusive Fitness r = coefficient of relatedness N = number of offspring

8. Hamilton’s rule Br > C  The altruistic/helpful behaviour will spread in the population if the NET benefit to the recipient x coefficient of relatedness is greater than the cost suffered by the altruist

9. Cooperative breeding In some species, younger individuals forego their own reproduction to help others rear offspring White-fronted bee-eaters

10. Cooperation among Florida scrub jays (Aphelocoma coerulescens)

12. The relationship between the number of Florida scrub jay helpers and the breeding success of the experienced parents. Helpers do not increase the number of eggs laid.They do, however, increase the chances that the eggs will hatch and that the young will survive to become independent. (data from Woolfenden 1975)

14. The relationship between the number of blackbacked jackal helpers and the number of the pups. (Moehlman 1979) Cooperation among blackbacked jackals (Canis mesomelas)

15. Eusociality Type of social organization of animals  Reproductive division of labour (reproductive and nonreproductive castes)  Cooperation in the care for young  An overlap between generations

16. Hymenoptera: ants, bees and wasps S C E

17. Isoptera - all termites

19. Ants show caste polymorphism

20. Female parent Diploid Male parent Haploid Male offspring Haploid Female offspring Diploid

21. Haplodiploidy in eusocial insects The genetic contribution of a male and female of a haplodiploid species. The maternal contribution is only half of the female offspring’s genes. Since the mother is diploid, sisters have 25% of their genes in common through their mother’s gametes.The father is haploid, so his sperm are all identical. As a result, sisters have 50% of their genes in common through their father’s gametes. Male offspring are haploid. Each male’s entire set of genes comes from his mother. Thus, the average degree of relationship among brothers is 50%.

22. Eusociality in the naked mole-rat

24. Naked mole rats

26. Reciprocal Altruism (reciprocity) An action by an individual (the donor) that helps another individual (the recipient), and that is subsequently repaid by the recipient. Conditions necessary for reciprocal altruism to evolve:  Opportunities for repayment  Individual recognition  Discrimination against cheaters  Benefit to the recipient > cost to the actor

27. Prisoner’s Dilemma