Lecture 26-29: Hammond Flashcards
What are some examples of social behaviour?
Parental behaviour, mating behaviour, extended families, cooperation. Interspecific interactions, predation, chance groupings are NOT SOCIAL BEHAVIOUR
Define adaptations?
Characteristics which increase reproductive fitness –> generally the outcome of selection, either natural or selective
What is the action of selection?
Doesn’t generally affect groups –> mutant in a group could go against the rest of the group and be successful. Normally acts on traits that are controlled by genes made up alleles.
What are the four types of social interactions?
Cooperation: recipient + / donor + Altruism: recipient + / donor - Selfish: - / + Spiteful: - / -
Benefits of living in groups?
Greater protection from predators Increases resources obtained, located and maintained Mating opportunities Reduced infanticide
How does group living lead to greater protection from predators?
Dilution effect- individual predation decreases Increased vigilance - many eyes hypothesis Selfish Herd - trying to get into centre of the group —> underlying drive is selfish but appears as cooperation
How does group living lead to increased obtaining, locating and maintaining resources?
Increased group size –> Increased kill size, decreased chasing in a hunt (African Hunting Dogs) Cooperation of ant queens: unrelated queens form colonies together to increase the success rate. When workers are produced they then go and forage –> queens then fight to the death for nest dominance.
How does group living lead to the creation of mating opportunities?
Lekking behaviour (Lek- display area of congregated males to attract females), males defend very small territories and females select. Male mating success correlates with display activity, aggression and lek attendance. Increases with male trait extravagance. Position in groups also dictates how successful the male will be- central males are more successful
How does group living lead to less infanticide?
Lions killing cubs - If they live in groups then lions less likely to kill cubs
What are the costs of living in groups?
Increases competition- mates and resources Increased conspicuousness to predators Increased chance of disease.
What are the four characteristics of eusocial behaviour?
Adults live in groups Cooperative care of juveniles- caring for individuals which are not their own. Division of reproduction Overlap of generations
Explain the structure of the naked mole rats groupings?
75-80 individuals living in a complex burrow with 1 queen and 1-3 breeding males, everyone else workers Workers can compete with queen to become breeding queen –> morphological change (non-reproductive state –> reproductive state) Low extrinsic mortality so can live to up to 300 years.
In what insect species is eusociality seen?
Hymenoptera (ants, some bees and wasps) Termites and cockroaches
What adaptations are often seen with eusociality?
Role specialisation: soldiers, leaf-cutters, driver ants
What is the relatedness like in eusocial insects?
High relatedness between workers because they are from the same mother - Can be a single male or multiple males but males always haploid.
What are the problems with altruism and cooperation?
Altruism: appears incompatible with natural selection Cooperation: it is possible for individuals to cheat
How does kin-selection explain altruism?
Helping individuals which share copies of the same genes. Relatedness x benefit > cost - Relatedness is higher in eusocial insects than other species, low relatedness would mean cost > benefit
What are examples of kin-selection?
Parental care- relative offspring care - If a long tailed tit fails with its nest then it will go and help relatives set up a successful nest - Fostering chicks and seeing who they go an help after —-> chicks which attempt to help will help those which they think are their parents (foster parents)