Exam 2 Flashcards
1
Q
Reciprocity
A
- Also known as reciprocal altruism
- in which a helpful action is repaid at a later date by the recipient of assistance
- An exchange of altruistic acts
2
Q
Genetic Constraints Model
A
- Monogamous species often share traits
-> High male to female associations
-> Bi-parental care offspring
-> High aggression towards strangers
-> High corticosterone and vasopressin
-> Low testosterone
Ex: Prairie voles and meadow voles
3
Q
Benefits of Group Living
A
- Increased protection
- Foraging Efficiency
- information center
- > where to find food
- better prey capture
- defending renewable resources
- > food - Energetic Efficiency
- conservation of heat
- locomotory efficiency
- > ex with lobsters walking in single file - Reproductive Efficiency
- finding a mate
- increased offspring survival
- > rearing close kin
- > reciprocal nursing
- > communal defense
ex: female lion protection offspring from males
4
Q
Asexual reproduction - GYNOGENESIS
A
- occurs in the amazon molly fish
- all female reproduction
- Female produces daughters
- daughters produce their own daughters that are genetic clones of one another
- Males are in the tree because females have to get egg stimulated by a sperm cell to have first cell division occur
- > Trick males of other species to mate with them to start their cell division of their eggs but do not incorporate the males DNA
- ALL FEMALE RACE
5
Q
H1 Female Defense Polygyny
A
- males defend multiple females by preventing access by other males
- > keep them in close proximity and in groups, then defends the entire group
- effective only if females remain together and have reproductive synchrony
- > need to be receptive at the same time
6
Q
What is the purpose of a Lek?
A
- a lek is an aggregation of males gathered to engage in competitive displays
- > involves male competition and female choice
- > formed before or during the breeding season
- males compete directly for matings by displaying for multiple females
- location can affect Lek and mating success
- > Lek’s do not stay in the same location
- -> movement of lek’s suggest that females come for the males rather than the resources they need
- the most successful male gets the majority of the matings
- > mating success decreases exponentially for remaining males
7
Q
Mutualism
A
- cooperation between species.
8
Q
Why do females invest more in offspring care than do males?
A
- Males are less certain about their paternity to an offspring, whereas females are certain the offspring is theirs
- > males do not want to expend energy on offspring that might not be theirs
- Males have more to gain by mating with multiple mates than females
- > so they will skip paternal care and resources to mate with more females
- Paternity assurance in males vs females
9
Q
Polygyny
A
- one male mating with many females
- most common method in species
- when polygyny decreases, male parental care increases
- > males could be competing for the females themselves, or resources the females need
- can also gather near a lek, where they do not defend females or the territory, but instead they gather at a place where females can view multiple males
- can occur under these circumstances:
1. Female defense Polygyny
2. Resource Defense Polygyny
3. Lek
10
Q
Why is social monogamy not a good predictor of genetic monogamy?
A
- Because of Extra Pair Copulations (EPCs)
11
Q
Kin Recognition: Environmental
A
- “Nest mate effect”
- Altruism directed toward individuals that were raised together
- Does not require any genetic similarity
Ex: Beldings ground squirrels accept nest mates regardless of relatedness
12
Q
Measuring Relatedness
A
- coefficient of relatedness
- parent to offspring is r=.5
- half siblings are r= (.5)^2 = .25
- full fiblings are r = (.5)^2 + (.5)^2 = .5
- consider each relatedness as .5 and each arrow is the exponent
- draw arrows from one sibling to another
- If take different routes to get to the sibling must add a + sign
13
Q
Spite
A
- A behavior which is costly to both the actor and to the recipient where cost and benefit are defined on the basis of the lifetime direct fitness consequences of a behavior.
- Favored by selection if you If you harm a recipient that is less related to you than others in the population
- > it benefits those that remain
- A behavior which is costly to both the actor and the recipient
14
Q
Inclusive Fitness
A
- the sum of an individual’s direct and indirect fitness
- The effect of one individual’s actions on everybody’s number of offspring weighted by the relatedness.
- inclusive fitness (individual i) = direct fitness (individual i) + fitness benefit (individual j) x relatedness of i to j
- wi= ai + S bj x rij
ai = effect of i’s behavior on i’s fitness
bj= effect of i’s behavior on the fitness of relative j
rij= coefficient of relatedness of i to j
15
Q
Sexual Conflict
A
- Sex Role Reversal
- females compete for access to males and are more choosy
- males perform parental care
- when males can not mate with many females, females compete for the best male
- females with exaggerated traits indicate the best quality to males - Extra pair copulations
- Antagonistic coevolution
- Male-male sperm competition
- males compete to fertilize eggs
- multiple mechanisms
- Coolidge effect - Cryptic female choice
16
Q
Kin selection
A
- process by which traits are favored because of their beneficial effects on the fitness of relatives
- Altruism favored when a related recipient is benefited much more than the actor pays in cost (hamilton’s rule)
- rB – C > 0
- Provisioning of siblings
17
Q
How can you distinguish whether a female is choosing a male for good resources, good genes, or attractive sons?
A
- good resources
- > males that guard good resources are chosen by females, but if a female does not require that specific resource it can be ruled out
- good genes
- > males with red coloration have fewer parasites and more body fat, therefore could be favored by females
- > if we find this is not the case with red coloration, then rule out good genes
- > same with Bright males, MHC alleles and asymmetrical body patterns
- attractive sons
- > once ruled out good resources and good genes, then find a correlation between female choosiness and sons genes
- > sons inherit the preferred trait
18
Q
PAPER: “Kin Recognition” Pfennig and Sherman 1995
A
- explores the mechanisms of how kin might recognize each other
- Extension of the kin selection model was used to explain how sterile workers in the eusocial insects might evolve even though they cannot pass on their own genes
- the traditional view held
that natural selection favored individuals that produced the greatest number of offspring - Hamilton said that natural selection must favor organisms that help any relative, because by doing so they increase their total genetic representation
-> inclusive fitness - A second explanation, optimal outbreeding theory
-> Optimal outbreeding theory
explains why many organisms prefer to mate with those to whom they are neither too closely nor too distantly related - kin recognition and cannibalism
19
Q
What resources do females need that males can defend?
A
- Some resources male will exchange for mating include
- > Defensive cavities, Nesting sites, Foraging patches, and Territories
20
Q
What are the benefits of extra-pair copulations for females? what are the costs?
A
- Benefits
- favored if the costs are low and occurs when females have the highest chance of fertilization without losing parental care
- extra pair mate has better gene indicators such as longer, brighter, or larger traits
- causes more sexual dimorphism, than if no EPC
- allows female to mate with a higher quality male if she has already mated with a low quality male - Costs
- increased chance for disease, difficult to fight off different type of sperm cells
- decreased life expectancy (Drosophila- fruit flies example)
- if the male was helping to provide parental care, the male may abandon nest and not care for the offspring if he thinks he is not the father
21
Q
Group living Predator Defense advantages and disadvantages
A
- Advantages:
- dilution effect
- selfish herd
- confusion effect
- communal defense
- many eyes effect (group detection - Disadvantages
- increased conspicuousness
22
Q
Bateman’s principle
A
- The idea that, since eggs require greater energy to produce than sperm
- females should be choosier sex and this should result in greater variance in the reproductive success of males.
23
Q
Environmental kin recognition may lead to thinking non-kin are really kin. How does this . mechanism lead to nest parasitism?
A
- this is because this type of kin recognition does not require any genetic similarity, unlike the other 3 mechanisms
- nest parasitism is laying eggs in the nests of other species
- parents will feed any found offspring in their nest because they think its their kin
- > allows for cheaters to fool females into raising an individual that is not their own
24
Q
Group living Foraging Efficiency advantages and disadvantages
A
- Advantages
- information center
- better prey capture
- defending renewable resources - Disadvantages
- interference competition
- resource limitation
25
Q
PAPER: “ The prairie vole: an emerging model organism for understanding the social
brain” McGraw and Young 2010
A
- demonstrating how monogamy may be favored by specific genes
- prairie voles will likely maintain their current trajectory becoming an unprecedented model
organism for basic and translational research focusing
on the biology of the social brain. - this model organism has exceptional potential to begin to guide us in understanding the genetic pathways and neurobiological systems that regulate aspects of sociality that are often impaired in these patients.
- a model organism for
identifying mechanisms regulating complex social behaviors, which will directly impact the understanding of our own sociality and inform future treatment of psychiatric
disorders of the social domain.
26
Q
Antagonistic Coevolution
A
- evolutionary “arms race” between male traits and female traits
- traits that increase fitness in one sex will decrease the fitness in the other sex
- Sexual antagonistic co-evolution is the relationship between males and females where sexual morphology changes over time to counteract the opposite’s sex to achieve the maximum reproductive success.
27
Q
how do animals recognize kin?
A
- three primary mechanisms
1. Recognition Alleles - Greenbeard affect
- altruism directed only towards individuals with the same altruism gene
2. Genetic - armpit effect
- altruism directed only towards individuals that share many genes
- many times, similar genes = similar smell
- > why it is called the armpit effect
3. Environmental - Nest mate effect
- altruism directed towards individuals that were raised together
- do not require any genetic similarity
28
Q
Direct Fitness
A
- the genes contributed to the next generation by personal reproduction
- The component of fitness gained through the impact of an individual’s behavior on the production of offspring.
29
Q
What is an evolutionary stable strategy(ESS) and what does it have to do with games theory?
A
- ESS is a genetically distinctive set of rules for behavior that when adopted by a certain proportion of the population cannot be replaced by any alternative strategy
- an evolutionary stable strategy is Tit-for-Tat (TFT)
- > if you are playing the game with the same person over and over
- > if play a new opponent the ESS is ALLD
- ESS is the theoretical solution to a games theory problem!
30
Q
Natural Selection
A
- deals with genetic differences
- it also deals with adaptability to the environment and chances of survival
31
Q
Prisoner’s Dilemma Model: assumptions of PAVLOV
A
- Better vs. ALLC
- Worse vs. ALLD
- Better if occasional mistakes are made
- PAVLOV does not lead to an excess in cooperation or defection like TFT does
32
Q
Altruism
A
- A behavior which is costly to the actor and beneficial to the recipient where cost and benefit are defined on the basis of the lifetime direct fitness consequences of a behavior
- Helpful behavior that raises the recipient’s direct fitness while lowering the actor’s direct fitness.
33
Q
Kin Discrimination
A
- An individual different reaction toward others based on the degree to which they are genetically related
- offspring provisioning
- avoiding cannibalism
- avoid inbreeding
34
Q
Good Genes in Female mate choice
A
- A model of sexual selection in which females choose to mate with males that possess traits that are indicative of good health and vigor
- > that is, traits that are best suited to their particular environment.
- females choose males based on superior genetic quality or superior genetic compatibility
- high quality males are:
- > resistant to parasites
- > better forager
- > higher survival
- genetic compatible males
- > decreased inbreeding cost
- > decreased autoimmune cost
- handicap principle
- females prefer symmetry in males
35
Q
Secondary sex characteristics
A
- Morphological traits that differ among the sexes that usually do not develop until sexual maturity
- Most secondary sex characteristics are assumed to have been favored by sexual selection.
36
Q
Intersexual selection
A
- Traits are selected that favor one sex’s ability to attract and mate with the other sex. - Female choice of males is much more common than male choice of females.
- > females select more agreeable partners based on the males ability to excite, or charm them
37
Q
Describe Four different routes to achieve cooperation
A
- Kin selection
- helping individuals that share the same gene copies - By-product Benefits
- cooperation arises as a by-product of an otherwise selfish act - Reciprocity
- helping another individual because that individual will then help them back - Enforcement
- rewarding cooperation and, or punishing free riding
38
Q
Alternative mating strategy
A
- Any variant of one sex that differs in morphology and/or behavior that has some reproductive success against the predominant mating strategy
39
Q
When is altruism ever favored by natural selection? When should individuals discriminate kin from non-kin?
A
- When the benefit of helping close kin is greater than the cost to one’s self
- altruism is selfish
- When performing altruistic behaviors.
40
Q
H3 More Resources/Material Benefits Hypothesis Polyandry
A
- Increased material benefits due to nuptial gifts or extensive male parental care
- offsets the cost of mating with more than one male
- An explanation for why females of some species might mate with several males per breeding cycle with benefits coming to polyandrous females because they gain access to material benefits controlled by several males
41
Q
Parental care model
A
- Mating system is determined by the distribution of parental care among the sexes
- male only parental care suggests polyandry
- biparental care suggests monogamy
- female only parental care suggest polygyny
- does not work well with mammals because there is not an opportunity for males to be a primary caregiver since they can not lactate
- > in mammals can only have monogamy or polygyny
- In fish it is the opposite, when male only parental care occurs have polygyny and when female only parental care occurs have polyandry
42
Q
Cooperation
A
- Where individuals perform activities that are adapted to increasing the fitness of others because this ultimately contributes to their own direct or indirect fitness.
43
Q
Gamete sizes in males vs females: Disruptive Selection
A
- major difference between males and females is the size of their gametes
- > Theory which underlies the driving factor that is associated with the theory of sexual selection
- Disruptive Selection favors the more extreme traits as opposed to the intermediate traits
- > larger female gametes have greater energy and thus higher success
- > smaller male gametes have greater mobility and thus higher success
- -> therefore disruptive selection should favor larger and smaller gametes
44
Q
Socially Coordinated Behaviors
A
- Where individuals adjust their actions to the presence or activities of others so as to maximize their own immediate direct fitness.
45
Q
PAPER: “The evolution and significance of male
mate choice” Edward and Chapman 2011
A
- relatively infrequent case of male choice
- we provide a synthesis of the theory on male mate choice and examine the factors that promote or constrain its evolution
- the evolutionary significance of male mate choice and the contrasts in male versus female mate choice
- They conclude that mate choice by males is potentially widespread and has a distinct role in how mating systems evolve.
- in addition to variation in female quality, a key factor in the evolution of male mate choice is the availability of females relative to the capacity of an individual male to mate with those females
- male investment in mating effort should also be considered, as this reflects the costs of mate attraction and intrasexual competition incurred by males
- future work would benefit from greater comparison of
the fitness benefits, costs of mate assessment and the
strength of selection arising from male relative to female
choice.
46
Q
Kin Recognition
A
- The capacity of an individual to react differently to others based on the degree to which they are genetically related.
- Recognition alleles
- Genetic
- Environmental
47
Q
PAPER: “One Giant Leap:
How Insects Achieved
Altruism and Colonial Life” Wilson 2008
A
- once a proponent of the kin selection hypothesis, now says that kin selection may not be the reason behind eusociality.
- successful bc organized groups beat solitaires
in competition for resources, and large organized groups
beat smaller ones of the same species - rare because it requires collateral altruism, which is behavior benefiting others at the cost of the lifetime production of offspring by the altruist
- argues that the origin of altruism leading to eusociality cannot be deduced by aprioristic reasoning based
on general models. - It can, however, be revealed by reconstructing actual histories with empirical data.
- Kin selection theory is not wrong; it is simply relatively
ineffective, even inapplicable in its present form to most empirical research. This basic weakness has a great deal to do with what its defenders also stress as its basic strength, its all- inclusiveness - Depending on definitions, group selection and individual direct selection are considered the key to the origin of eusocial evolution, with
pedigree kin selection playing a minor role at best
-> or on the opposite side, kin selection is considered the key to eusocial evolution
48
Q
Attractive Sons/ Fisher’s Runaway Sexual Selection in Female mate choice
A
- Fisher’s Runaway Sexual Selection
- A form of sexual selection that occurs when female mating preferences create a positive feedback loop favoring both males with these attributes and females that prefer them
- the connection to having good genes is lost
- genetic correlation between male trait and female preference
- differs from handicap principle because the trait is not an honest indicator of the male’s genetic quality
-> sons inherit the preferred trait and daughters inherit the preference
-> will keep developing the ridiculous trait as long as females have a preference for it
—> checked by natural selection, will gain trait until they can no longer survive
Ex: stalk eyed flies - female flies for some reason prefer males with eyes that are spread further apart on the end of stalks
- this in no way correlates to healthiness, it is just a random trait the females like
49
Q
Give an example of sexual dimorphism.
A
- Coloration in male and female lizards, mallard ducks, antlers in deer, size differences in males and females of many species.
50
Q
Evolutionary Stable Strategy (ESS)
A
- A genetically distinctive set of rules for behavior that when adopted by a certain proportion of the population cannot be replaced by any alternative strategy
51
Q
When should individuals discriminate kin from non-kin?
A
- if you can not discriminate kin from non-kin, natural selection will not favor you to be an altruist
- individuals should discriminate kin from non-kin when performing altruistic behaviors
- > for the indirect fitness
- to prevent inbreeding
- to avoid cannibalism of own relatives
52
Q
Games Theory
A
- An evolutionary approach to the study of adaptive value in which payoffs to individuals associated with one behavioral tactic are dependent upon what the other members of the group are doing
53
Q
Give an example of sexual selection
A
- Female elk will only mate with males that are big and strong and can hold their own in a showdown with an opposing male
