Social Behaviour Flashcards
Define social behaviour
Social behaviour = behaviour associated with interactions between conspecifics (and allospecifics)
Why is social behaviour more relevant for groups of animals instead of solitary animals?
Social behaviour allows groups to function
This is not to say that solitary animals don’t interact but it’s less frequent
Mechanisms of social behaviour are what allows groups to function
Give examples of animal groups
Small family groups where all individuals know each other
Massive crowds that are little more than aggregations of individuals together
Lots of explanations for why animals live in groups is related to cooperative behaviour where there can be mutual benefits with working together
Define cooperative behaviour
Cooperative behaviour = behaviour providing benefit to another and selected upon due to benefit (at least partly)
Give an example of cooperative behaviour
Kin selection
Explain what kin selection is
Kin selection is a cooperative behaviour between relatives
With Kin selection, helping out your family members can actually increase your own fitness
For kin selection to occur you need heritable altruistic behaviour because it needs to be selected upon to increase fitness
Siblings share half of the same DNA
So if you help raise 2 of your siblings offspring that has the same fitness as if you raised 1 yourself
Also if the animal breeds itself at a later date it will have gained offspring rearing experience and learned how to do it from other individuals
For kin selection to work Hamilton’s rule must be in affect
What is Hamilton’s rule?
Hamilton’s rule = Benefits to the relative’s chances of successful reproduction must outweigh cost to aiders own reproductive success
What is mutually beneficial cooperation?
Mutually beneficial cooperation is cooperation between animals that aren’t related
What are the 2 types of mutually beneficial cooperation and explain what they mean?
1) Intra-specific mutualism
Intra-specific mutualism is where cooperation generates immediate shared synergistic benefits exceeding costs
2) Reciprocal altruism
Reciprocal altruism is where there’s an exchange of resources/services with temporary net costs exceeded by later benefits
Reciprocal altruism will be more likely to occur in stable social groups where the individuals meet often and spend long periods of time together
If they don’t meet often then it can be easy to cheat the system
Cases where reciprocal altruism are most likely to occur are when there’s quick reciprocation to avoid cheating or exploitation
You need to be careful at looking at mutually beneficial cooperation because some cooperative behaviour can be explained by manipulation or as a by-product
Explain this
Manipulation may occur where a dominant individual coerce subordinate individuals to help them increase or avoid costs to fitness
This manipulation comprises the subordinate animals fitness while increasing the dominant animals fitness with no return of the benefits
Some cooperative behaviour may be a result of accidental cooperative behaviour
An example is that a subordinate animal will stay near a dominant animal and groom them to avoid harassment from other individuals
What 4 things does fake cooperative behaviour do?
1) Not designed to assist a partner
2) Have no reciprocity
3) Offer immediate benefits for 1 party
4) Possibly unequal in cost
True or false
Even though there are costs associated to fitness due to the fake cooperative behaviour the overall fitness outcomes of being in a group may outweigh the associated costs
True
What are the 3 benefits of group living in the context of feeding?
1) Food detection
2) Prey capture
3) Food protection
True or false
There is a trade off between group size and the amount of food available
True
Explain what is the by-product of group living in terms of feeding
A by-product of group living is that communal roosts/nesting sites may act as ‘information centres’
This means that individuals who are less successful at food detection can wait at these information centres and then follow a more successful individual
This may seem like a cost to the successful individual but there are some benefits such as:
- mutual benefits associated with predation
- cost of successful individual can be relatively low if food source in large
- Some species can judge when it’s best to share
How can group living aid in prey capture?
Predators work in groups to capture bigger prey items which would be unavailable or too dangerous for a solitary hunter
Also if a group of predators attack a prey item or a herd of them it can increase prey panic leading to uncoordinated feeling
This makes it easier to pick off an individual prey item
What are the 6 benefits to group living in terms of predation risk?
1) Detection of predators
2) Dilution effect
3) Predator satiation/swamping effect
4) Selfish herd effect
5) Predator confusion
6) Defence against threat
True or false
The less individuals there are the less time an individual needs to be vigilant so they can spend more time foraging
False
The more individuals there are the less time an individual needs to be vigilant so they can spend more time foraging
In some species there are sentinels, what do they do?
Sentinels will look out for predators as the rest of the group forages and will alarm call when a predator is spotted
Why do animals take up the sentinel role?
Animals take up the sentinel role once they’re full and escape faster since they’re the first to see the predator
Also individuals take turns being sentinels
Why do animals take up the sentinel role?
Animals take up the sentinel role once they’re full and escape faster since they’re the first to see the predator
Also individuals take turns being sentinels
How is alarm calling good?
Alarm calling may seem like a cost to fitness since it attracts the predators attention to the individual calling
However it benefits the individual not alarm calling
Also if the individuals are related it increases the same genes in the population
It increases fitness if the individuals are related via kin selection
Explain the dilution effect in terms of predation risk?
The more individuals in a group the less chance each individual has of being picked off by a predator
So increased group size dilutes the risk of any one attack
This means that compared to a solitary individual your fitness is increased if you’re in a group assuming that the attack rate also does not increase with group size
Explain predator satiation/swamping effect in terms of predation risk?
If you’re group size is larger than the maximum intake the predator can consume then the predator is satiated before group size is decimated
In relation to dilution theory this method reduces the risk of predation even if there are multiple attacks
True or false
Predator satiation/swamping effect can act on how animals emerge after reproduction
An example is that mayfly emerge over a 2 week period in North America
True
Explain the selfish hers effect
The selfish hers effect benefits individuals instead of the whole group
It’s usually based on rank
So in groups, individuals in the middle of the group are safer
This is because a predator is more likely to pick out closer individuals which are on the outskirts of the group
Individuals will move to a safer position closer to the middle of the herd in order to avoid being predated
Individuals that do this are usually high ranking individuals
This increases the fitness of the high ranking individuals
Explain predator confusion in terms of predation risk
Large numbers of moving prey can impair predator targeting and capture of an individual
Some species enhance this with camouflage
Explain defence against threat in terms of predation risk
Some species will mob predators hunting by stealth
This undermines the predator as everyone can then see them
Also if the mob is attacking in a group then they have less chance of being injured if they’re distracting the predator and are all coordinating their attack
Defense against threat reduces fitness costs for each individual in that group as it reduces the chance of being injured or picked off
What are the 3 benefits of group living in terms of social learning and information exchange?
1) Learning from conspecifics
2) Sensitive period
3) Knowledge may be culturally held by groups
Give examples of how who an individual learns from affects information
The most important influence on young animals that learn from conspecifics is usually the maternal influence
Research also suggests that individuals may pay more attention to demonstrators of higher rank over those who are more successful
True or false
By learning from other individuals it can increase your own fitness as you learn things without the potentially risky trial and error
True
Explain what is meant by sensitive periods in terms of social learning and information exchange
With social learning there are periods throughout an animals life where specific learning has to occur
If that specific learning doesn’t occur that can impact on social behaviour and social interactions later in life
Give 2 examples of sensitive periods in terms of social learning and information exchange and explain what they are
1) Imprinting
This happens shortly after birth
Imprinting is where there is an attachment formed with a parent in order to increase the chances of survival and at the same time act as a template for future mating partners
2) Socialisation
Socialisation is where the animal has to have experiences of other animals of the same species in order to learn how to appropriately behave later in life
What is cultural transmission of behaviour?
Cultural transmission of behaviour is when a pattern of behaviour is passed on to succeeding generations without any genetic changes
What are the 4 other benefits of group living?
1) Energy conservation
2) Easy access to potential mates
3) Working together on shelter
4) Allo-grooming/allo-preening
What are the 5 disadvantages of group living (5 advantages of solitary living)?
1) Increased risk of predation
2) Risk of inbreeding and disproportionate mating opportunities
3) Increased risk of parasite and disease transmission
4) Cooperation requires cognitive investment (via recognition and memory) and frequent encounters
5) Resource depletion and competition for resources and spatial position in the group