Chapter 10 Life History Flashcards
Life history
llifetime pattern of growth, development and reproduction
Costs and benefits of reproduction
there is a tradeoff between the resource allocation for personal growth and resources for reproduction!
Costs and benefits associated with age at maturity
- the primary fitness advantage of delaying maturity is the larger initial body size obtained by individuals when they first reproduce.
- The primary cost of delaying reproduction (late maturity) is the increased risk of death prior to reproduction
How patterns of adult and juvenile mortality can influence evolution of age at maturity
Decreases in the ratio of adult/juvenile survival (low survival for adults relative to juveniles) appear to favor reductions in age at maturity
Reproductive allocation
tradeoff between current and future reproduction
Monogamy
formation of a pair between one male and one female
Polygamy
the acquisition by an individual of two or more mates
Polygyny
individual male, pairs with two or more females
Polyandry
individual female, pairs with two or more males
Sexual dimorphism
2 DISTINCT SEXES! MALE AND FEMALE.. NOT ONE
Intrasexual selection
- competition for the opportunity to mate (HIGH PRESSURE)
- intra is inside sex
Intersexual selection (mate selection)
differential attractiveness of one sex to another (LOW PRESSURE LOTS OF
CHOICE)
-inter is between sex
Tradeoff in Size and Number of offspring
more quanity small offspring…
or less quanitity bigger offspring
R strategy animal
small body size, short-lived, fast growth rate, early reproductive development, large number of offspring (but low survival rate), and minimal parental care.
K strategy animal
larger body size, longer-lived, slower growth rate, delayed reproduction, fewer offspring, and developed parental care
Semeloparous NEED TO KNOW
an organism that sacrifices all its prospects by expending all its energy in one suicidal act of reproduction
Iteroparous need to know
organisms that produce more than once over their lifetime
S plant strategy
STRESS TOLERANT, delayed maturity, longterm energy storage and low growth
Darwinian Demon
reproduces as soon as possible after birth, reproducing continuously, producing LLARGE numbers of LARGE offspring that it will nurture and protect
Asexual vs sexual pros and cons
Asexual pro: all organisms are well adapted to local environment
Asexual con: if environmental factors change, the whole population can easily be whiped out due to lack of diversity in the population for handle different situations
sexual pro: more likely to survivie environmental changes
sexual con: much more costtly in energy to be sexual cuz of LOTS OF PROCESSES
Relaltionship between body size and fecundity?
Direct Correlation. Bigger adults will produce more … at risk of death for being alive longer tho
Fecundity
of offspring produced per unit of time
In wet environment, which is smarter to have bigger seeds or smaller seeds?
Smaller + MORE SEEDS, because all the seeds are able to be germinated cuz of abundance of water.
IN DRYNESS, BIGGER SEADS AND LESS SEEDS ARE BETTER DUE TO RETENTION OF WATER
ideal is LOTS of big seeds but that takes more energy
Which strategist is closest to carrying capacity?
K … meaning they are poor colonizers of new habitants because their rate of growth is sloooww
