Lecture 14- Animal collectives II

Question 1

many wrongs hypothesis

Answer 1

idea that groups are successful because when everyone guesses, the average of the guess seems to be about correct

Question 2

example of ‘democracy’ within a group

Answer 2

wild dogs- seem to make decisions using voting (‘rallying’)- more dominant dogs have more say though (their rallies more likely to catch on), so not entirely democratic

Question 3

how can collective behaviour be regulated?

Answer 3

‘colony threshold distribution’- idea that there are differences between individuals which can lead to different thresholds for behaviours, e.g. bees starting to ‘fan’ at different temperatures leading to a sort of gradient of the behaviour in a group context

Question 4

important ideas in collective locomotion

Answer 4

nearest neighbour difference, which helps mediate spacing in a group
attraction, repulsion, and alignment at specific distances away from an individual

Question 5

example of collective behaviour that isnt social

Answer 5

locusts- moving together towards food, but moving to get away from each other- contact at the rear triggers movement, sort of ‘chasing’

Question 6

when is an individual more likely to follow another?

Answer 6

when directional agreement, and number of initiators, is high

Question 7

group size and disease

Answer 7

social immunity can actually occur- lower disease spread through anti-infection measures e.g. effective waste removal and hygiene practises, organisational immunity e.g. in ants

Question 8

example of disease avoidance

Answer 8

lobsters seem to avoid nesting with infected individuals, visible disease might put them off as visible disease often means being infectious

Question 9

example of social immunity in ants

Answer 9

killing and disinfection with acid of infected individuals, for the good of the colony- illness signalling with chemicals to help promote this behaviour