Final Flashcards
direct parental care
taking care of offspring
ex. care of fertilized eggs, feeding, protecting
indirect parental care
investing in offspring before fertilization
ex. invest in gamete production, prepare natal environment, acquire and defend resources
when does parental care evolve?
benefits of care (lifetime reproductive success) outweigh costs of providing care
Costs of parental care examples
- increased predation risk
- reduced foraging time
- reduced future fecundity
- reduced opportunities to seek additional mates
Female parental care reasons
more likely to provide care due to anisogamy
- more to loose if offspring survive bc they’ve already invested more into producing gametes
male reasons for parental care
trade-off between parental effort and mating effort
evidence for trade-off between parental effort and mating effort
male fairy martins spend less time incubating eggs when there are more mating opportunities
evidence against male trade off between parental and mating effort
male sand gobies fan eggs to oxygenate them and females prefer males that spend more time fanning eggs
- no trade off when females prefer good fathers
Certainty of parentage
parents should only invest in care for offspring that are their own
certainty of parentage depends on mode of fertilization
internal - low male certainty
external - both male and female have high certainty
Paternity and parental effort example
male bluegills less likely to provide parental care to eggs when perceived possibility they might not be the father
Association with offspring and parental care
sex that fails to desert first is the one that cares
- also fertilization dependent
parental care and fecundity
related to body size
- males: good fecundity even if small
- females: larger = more gametes
- investment in care = time not spent getting resources to grow larger
female only care in mammals
predisposed to gestation and lactation
egg-feeding in frogs
associated w/ breeding in very small nutrient poor pools
Biparental Care
- common in
birds
Biparental care occurs when
- both parents can provide care
- care by both is essential for survival
- low food availability and high metabolic demand
How to make sure you provide for your own offspring?
- rule of thumb
- recognize your offspring
Rule of thumb
if there is a begging chick in your nest, it must be your chick, you should feed it
Learn to recognize your offspring
- individually distinct communication signals and the ability to learn them
ex. Cliff swallows
should parents reject unrelated young?
- mafia behavior of parasites
- not easy to discriminate “own” and “other”
- errors costly and unavoidable
group selection theory by wynne-edwards
selection acts at the level of the group, population, or species
what does group selection produce (wynne-edwards)
individuals that exercise restraint in reproduction/resource use for good of population
criticism of group selection by Williams and Dawkins
fitness is relative and genes that increase individual fitness will increase in frequency in population
benefits of group living
- improved foraging efficiency
- resource defense
- help and assistance
- more efficient locomotion
- reduced predation risk
cooperative breeding
non-parents, non-dependent offspring, and unrelated individuals help raise offspring
benefits of group living on predation
- dilution effect
- selfish herd effect
- improved detection
- confusion effects
- mobbing behavior
costs of group living
- increased competition for food
- reproductive interference
- opportunity costs
- increased disease transmission
- greater conspicuousness
altruism
cooperation benefits the recipient at a cost to the actor
reciprocity
one organism provides benefit to another, unrelated individual w/ expectation of future reciprocation
- only evolutionarily stable with repeated interactions
tit-for-tat may evolve in nature if
- benefit to recipient greater than cost to the actor
- opportunity for repayment likely to occur
- individuals able to recognize each other
kin selection
animals help relatives reproduce at a potential cost to their own reproduction
- hinges on inclusive fitness
inclusive fitness = direct + indirect
direct - things that maximize own survival and reproduction
indirect - things that max survival of non-descendent kin that share genetics
coefficient of relatedness
full siblings = 1/2
first cousins = 1/8
Hamilton’s Rule
genes promoting altruistic behavior will only spread is rB > C
r = coefficient of relatedness between actor and recipient
B - benefit (extra offspring produced
C = cost (offspring not produced)
Eusociality
cooperation by individuals other than parents in caring for offspring
- usually reproductive division of labor (sterile worker castes)
Eusociality and Haploid Sex Determination
R value for full sisters (.75) is greater than mother-offspring (.5)
- females incr inclusive fitness by helping mom raise full sisters (indirect)
other factors that influence eusociality
- increased r due to high rates of inbreeding
- extreme difficulty in establishing new colonies
How do animals decide where to live?
where is more resources
- frequency dependent - are there competitors
Ideal Free Distribution
as population density increases, avg fitness of being in patch decreases
- choose best patch first, reach equilibrium where individuals experience same fitness in all patches
assumptions of ideal free distribution
ideal - individuals can accurately assess payoffs
free - individuals can move with no cost
individuals have equal competitive ability
fitness decreases as density increases bc of increased competition
Conspecific Attraction
cue of habitat quality
- males attracted to sound of same species males in wood frogs because that’s where the females will be
general definition of communication
exchange of info from signaler to receiver in form of signal that passes thru some medium
functional definition of communication for signaler
increase chance that receiver chooses and action that is beneficial to the signaler
functional definition of communication for the receiver
increase chances of choosing the best action
- emphasis on info gathering
evidence of some innate quality of song in songbirds
deafened chicks raised in lab still vocalize even if it looks noting like normal song
development of birdsong
“sensory phase” - perceptual learning (learn template)
“sensory-motor phase” - procedural learning (match template)
Neural basis of song
sexual dimorphism in “song nuclei” created by organizational effects, increased by activational effects
function of song in male attraction
females prefer good copies of conspecific male songs
- size of nuclei correlated with accuracy of song learning
- depends on nutrition
HONEST INDICATOR OF DEVELOPMENTAL RESISTANCE TO NUTRITIONAL STRESS
meme
unit of cultural evolution passed from individual to individual via imitation
benefits of pest control using pheremones
- decrease use of more costly pesticides
- increase crop yields
hypothesis for stereotypic behavior in zoo animals
- natural foraging modes
- natural activity levels
- natural ranging
reducing stereotypic behaviors
- enrichment
- increased activity levels
- social enrichment (pheromones and natural sounds)
