L5 Evolutionary Choices Sex and Life Histories Flashcards
(29 cards)
Life History Theory
Study of evolutionary strategies affecting reproduction and survival.
Sexual Reproduction
Reproduction involving the fusion of gametes from two parents.
Asexual Reproduction
Reproduction without the fusion of gametes, producing clones.
Genetic Variability
Diversity in gene frequencies within a population.
Darwinian Fitness
Reproductive success relative to others in the population.
Costs of Sex
Energy and risks associated with finding mates.
Benefits of Sex
Increased genetic diversity and adaptability of offspring.
Bdelloid Rotifers
Asexual organisms that utilize horizontal gene transfer.
Hermaphroditism
Organisms possessing both male and female reproductive organs.
Iteroparous
Species that reproduce multiple times throughout their life.
Semelparous
Species that reproduce only once before dying.
Survivorship Curves
Graphs showing survival rates at different ages.
Type I Survivorship
High survival in early life, rapid decline later.
Type II Survivorship
Constant mortality rate throughout life stages.
Type III Survivorship
High mortality early, low mortality for survivors.
Trade-offs
Balancing energy allocation between growth and reproduction.
Sex Determination
Mechanism by which an organism’s sex is established.
Chromosomal Sex Determination
Sex determined by specific combinations of sex chromosomes.
Temperature Sex Determination
Sex determined by environmental temperature during development.
Protandrous
Species where individuals start as males, can become females.
Protogynous
Species where individuals start as females, can become males.
Coho Salmon
Exhibit alternative reproductive strategies: jacks and hooknoses.
Atlantic Cod
Type III species, high fecundity, long lifespan.
Fecundity
Reproductive capacity of an organism, often measured by offspring number.
