Animal Behaviour
Animal Behaviour Overview
Course Identification
Course Code: Bio 3436
Relevant Psychology Course: Psychology 3221G
Kin Recognition Mechanisms
Kin Recognition Definition: The ability of an organism to identify its relatives.
Methods of Kin Recognition:
Spatial Distribution: Recognition based on geographical proximity.
Association: Notable methods such as imprinting.
Phenotype Matching: Ability to compare one's phenotype to those of potential kin or self.
Perceiving Genetic Relatedness
Odour as a Detection Tool in Mice: Genetic relatedness is perceivable through scent cues. Mice select mates based on their Major Histocompatibility Complex (MHC) alleles.
Role of MHC in Altruism: MHC allele recognition may influence altruistic behaviours within social structures.
Major Histocompatibility Complex (MHC)
Function of MHC Genes:
Encode cell-surface proteins that bind to antigens, presenting them to T lymphocytes, aiding in immune response.
part of immune system
bind to surface proteins and tell them where to attack
Significance in Olfactory Communication:
MHC genes bind volatile carboxylic acids, altering the odour of mouse urine, and may affect the olfactory signature through its impact on gut microflora.
mice can detect these odeurs and detect similarity in MHC genes of themselves and mouse they are interaction with
want to promote out-brading
Mating Preferences in Mice
Female Mice Mating Behaviour:
Females avoid mating with males that share MHC alleles, promoting genetic diversity (out-breeding).
In contrast, females prefer to nest with and retrieve pups of females sharing MHC alleles.
similar study done with humans… men workout in shirt and women chose guy they shared the least amt of MHC alleles with
Human Preferences: Women show preference towards men with different MHC alleles, which may enhance genetic variability in offspring.
Forms of Social Behavior
Definition of Social Behaviours: Occur independently of kin relationships but carry fitness implications.
Fitness Consequences of Social Behaviours: All social interactions can influence individual reproductive success and survival.
Social Behaviour Framework
Classification of Social Behaviours Based on Outcomes:
Mutual Benefit: Actions that provide advantages for both the donor and recipient.
ex. paper wasps → dom queen lays eggs and other queens are subordinates → assumed that subordinate are related to dominant queen but while a lot are, some aren’t related at all
why would you forgo your reproduction if you aren’t highly related to the ween
often subordinate queen inherits the nest when the dominante queen dies, ensuring that the subordinate queens still have the opportunity to reproduce in the future while contributing to the colony's success in the meantime.
dom queen has almost a monopoly on reproduction but not completely so some subordinate are laying and hatching eggs
Altruism: Considered selfless acts where the donor incurs a cost while benefiting the recipient.
Cooperation: Working towards a common goal that benefits involved parties.
Selfishness: Behaviours that solely benefit the individual.
Spite: Actions that cause harm to others without any benefits to oneself.
Examples of Mutual Benefit
Paper Wasps Research:
Observations indicate multiple families may nest together.
Structure involves a dominant queen and subordinate queens, suggesting insights into kin selection within communal living.
Inherited Nests Study
Empirical Data: Reported per capita number of pupae based on group size suggests strategies of bee nesting and reproductive success.
Data points indicate variations in success dependent on solitary founding versus subordinates (inheritance).
subordinate reproductive output is better than solitary foundresses
group size is important → in a small group size there is no protection against predation or worker force
subordinates that inherit
subordinate that aren’t related have low cost high benefit bcs they have chance of inheriting the nest
Altruism and Cooperation
Reciprocal Altruism Definition (Trivers, 1971): A form of altruism where individuals act in a way that is temporarily disadvantageous with the expectation of a future benefit.
- /+ relationship
Androclès and the lion, encountered a lion with thorn in foot removes thorn, lion is grateful → was sent to stadium to fight lion… lion recognizes the favor and spares the individual's life in return, demonstrating the principle of reciprocal altruism where cooperative behaviors can enhance survival chances in social species.
blood sharing in vampire bats → go out to feed every night and if they go too long without feeding then they get to their starvation point
race against time.. feed up and get really full and they continuously loose weight until they can eat enough
don’t need a full meal just need enough to get them to next feeding
if one bat has more blood than it needs it can afford to give up a little bit
recipients need some food to give them another opportunity to feed which gives them another chance to feed
the benefit to the recipient is bigger than the cost for the donor; this reciprocal behavior fosters a social bond between the bats and increases overall survival rates within the colony.
Requirements for Reciprocal Altruism:
Benefits to the recipient (B) must outweigh the cost to the donor (C): B > C.
Necessitates reciprocation, often facilitated by:
Repeated interactions among the individuals.
Extended lifespan of both parties.
shot lifespans = not likely to meet each other again
Low dispersal rates, facilitating continued interactions.
opportunity for reciprocation
Models of Altruism
Three distinct models outlining the mechanisms by which altruism may evolve:
Randomly Dispersed: Altruism selected against; behavior is unlikely to perpetuate.
Kin-Biased Altruism: Calculated with kin selection criteria; measured by relatedness, expressed as rB - C > 0, where r is the degree of genetic relatedness.
it explains a lot of situations but doesn’t explain everything
Reciprocal Altruism: Altruism backed by mutual benefits; requires that B > C and acknowledges the significance of reciprocation in relationships.
Selfishness and Spite
Definition of Selfishness in Animals:
Common examples include kleptoparasitism, where one species steals food from another (e.g., Drongo bird stealing food).
individual act in their own selfish interest so that they can get their genes into the next generation
like with drongo making fake calls to steal meercat food
Evolution of Spite: Spiteful behaviours could evolve if they ultimately confer some sort of long-term benefit to the individual demonstrating spite.
shouldn’t happen but there are ways that we can see this as adaptive
are many instances that policing happens in social animals to can be seen as spite
ultimatum game: A scenario where participants can choose to punish others at a cost to themselves, suggesting that spiteful actions can serve to maintain cooperation within a group.
actor gets to decide if they both benefit or if they should be selfish → if the OG actor was selfish and make the recipient the new Actor, monkey will pay forward the negative outcome 75% of the time and positive outcomes 80% of the time. This indicates that social animals, like monkeys, often enact forms of accountability and punishment that reflect their experiences, promoting a balance between selfish behavior and the need for overall group harmony.
Testing Spite in Social Animals
Research Findings (Leimgruber et al. 2014):
Experiment involving monkeys and children showed tendencies to "pay forward" negative outcomes at rates of 75% (monkeys) and 72% (children) as well as positive outcomes at 80% (monkeys) and 70% (children).