6.10. (9/30) Reproductive Strategies and Social Relations Flashcards
How do we define females in ecology?
they produce larger, energetically costly gametes
How do we define males in ecology?
they produce smaller, less costly, gametes
What are hermaphrodites?
combined male and female function in the same individual
what conditions favor hermaphrodism?
- low mobility: limits competition
- not using the same resources/ doing things at different times
- sharing costs for male and female function (common)
monoecious plants
when the plant has separate male and female flowers on its being
dioecious plants
the plant has one sex
sequential hermaphroditism
Can switch sex if need be
ex. clownfish
simultaneous hermaphroditism
- both sexes & both gametes
- at sexual maturity
ex snail, plants
what determines the sex of reptilian offspring?
temperature
How does polygynous breeding work?
one male with many females
How does polyandrous breeding work
one female with many males
promiscuous breeding
breeding with different individuals
monogamous breeding
breeding with one individual for a short period of time or lifetime
fecundity
how fast an individual can produce offspring
what does a female’s reproductive success depend on?
ability to make eggs
what does a male’s reproductive success depend on?
the number of eggs he can fertilize
what determines a female’s fecundity? what about a male’s
- her ability to gather resources
- his ability to mate with many females
sexual selection
when there are differences in reproductive rates because of mating success differences
sexual dimorphism
males and females look different
intrasexual selection
individuals of one sex compete among themselves for mates
intersexual selection
members of one sex consistently choose mates on the basis of a particular trait(s)
why does sexual selection act upon the male species?
energetic cost
intersexual selection: good health hypothesis
when the female is looking for a suit of traits that are related to a male’s health
intersexual selection: good genes hypothesis
stalked-eyed flies choose wide-eyes because the narrow eye is linked to a sperm defect
runaway sexual selection
females drive further elaboration of male traits
what might counterbalance runaway sexual selection?
natural selection
handicap hypothesis/principle
extravagant appearances occur because it shows an individual has high fitness and are good at obtaining energy from the environment to look pretty
*successful despite handicap is healthy
*probably incorrect
what is important to remember about evolutionary theory, reproductive success, and duration of life
reproductive success is more important than how long a species lives
sexual selection in guppies
- ## high predation = less pretty
o morph
b morph
y morph
rock-paper-scissor scenerio
why are pipefish the exception?
reversed roles
- colorful female
- female deposits gametes to male
- female competes for mates
social animals
- found in groups
- some fish for protection
- sophisticated
what are the advantages of group living?
- less time looking for predators
- less time eating food
what are the disadvantages of group living?
- spend more time looking for food
what is sentinel behavior?
what is altruistic behavior?
cooperative breeding: inclusive fitness and kin selection
- individual overall fitness not just a function of offspring directly produced
cooperative breeding:
what is hamilton’s rule?
what is cooperative breeding?
which species engage in cooperative breeding?
sub-saharan africa
woodhoopoes
why do woodhoopoes breed cooperatively?
- increase inclusive fitness: raise and protect close relatives
2.
How could cooperative breeding evolve?
