Flashcards in Animal Behaviour-Co-operation between unrelated individuals Deck (16)
Give an example of two different species which have hunting associations.
Grouper fish and moray eel. Grouper leads eel to prey that grouper can't access. The eel then investigates and pushes food out so the grouper gets some too
Why are frogs often found under a tarantula?
Mutualism. Frogs protect tarantula eggs from ants and tarantula protects frog from predators
Is hunting co-operation an ESS?
yes! it is more beneficial to hunt together than it is for one to hunt and one not to. So there is no temptation to cheat
Give an example of a species that hunt together successfully?
American white pelicans hunt in groups of 2-30
What are some other benefits of hunting co-operation apart from more prey?
Protection against predators e.g House sparrows call more if there is a larger resource and harder to process. It may be impossible to take away the food so it is beneficial to attract more individuals so it can be protected whilst eating
What did a study with capuchin monkeys show about co-operation and coaction?
That some animals do not purposefully co-operate, they just happen to be reacting to the same stimuli. The experiment was that there was a lump of sugar to which the monkeys had to pull on the attached string to get it. The monkeys did not change their behaviour in the presence of another individual, they either did or didn't pull but were consistent in both cases
Did elephants show the same thing as the capuchin monkeys?
No, they learned to co-operate to get a food reward. Their actions are adjusted dependent on the presence or absence of a partner
Vampire bats often feed their buddies, even if unrelated, if they are unable to feed themselves for any reason. why? (tit-for-tat model)
The cost to the donor bat is very small and the benefits to the recipient bat is very big. They are more likely to help out individuals in the same subgroup as them so may be to do with the fact that they know they'll be helped back if they need it (reciprocal altruism) or it may be to do with the fact that they are being hassled and this is costing them more than the loss of the blood meal
How does the context (payoffs) affect co-operation between familiar and unfamiliar guppies?
They shoal together against predators more with familiar individuals, they show less aggression in competition for food to familiar individuals HOWEVER they do not co-operate more with familiar individuals for mates
The tit-for-tat model depends on remembering partners. How did a study using zebra finches prove this?
Naturally they remember the other individual and as long as both members keep co-operating, everything is fine. The experiment involved giving them corticosterone which impairs memory, co-operation declines
How did an experiment show that chimps can establish friends in which they trust and therefore co-operate more?
Chimps had two strings. One was a 'don't trust' string which gave out a non-preferred food to the chimp. The other was a 'trust' string which when pulled released a nicer food to their partner who could take half then give the original chimp the other half. It was found that those that spent more time together pulled trust more compared to when presented with a more unfamiliar chimp
Rhesus monkeys can act more aggressively to other individuals based on what?
On whether they call when they've found food and also who is watching their interaction. If an important social member is watching, male monkeys are more likely to call
Co-operative behaviour can change dependent on who is watching/the audience. How was this proven in a study with humans paying for milk in an honour system?
Images of either eyes or flowers were placed next to the milk throughout different weeks. The weeks in which eyes were present, people paid more for their milk than when flowers were present
In St. Peters fish, how does sex ratio of the population affect whether a parent is going to desert their offspring?
In female bias areas, females were unlikely to desert their offspring whereas males were. In male bias areas males were much more likely to care for the offspring and there was a reduced rate of care from the female
It is very uncommon that both parents desert an offspring
In burying beetles, why do females tend to care more for the offspring than males?
The female has to have a carcass to lay on so is limited in reproducing ability by the carcasses she can find. Males don't need the carcass, they just need a female