Lecture 10 Flashcards
3 most common life history strategies:
- equilibrium life history:high parental care , low fecundity, late maturation (ex: spiny dog fish)
2.Periodic life history: high fecundity, low parental care, late maturation (ex: sturgeon) - Opportunistic life history: early maturation, low parental care, low fecundity (ex: killifish)
Life history and environment
Equilibrium LF: high numbers in stable + predictable environment
Periodic LF: unstable + predictable environment
Opportunistic LF: unstable + unstable
Number of breeding opportunities
- Semelparous: spawn once then die
- Iteraparous: multiple breeding seasons
Type of spawning
- total spawners (synchronous spawners, ex: salmon)
- batch spawners (asynchronous spawners, ex: zebrafish)
Mating systems
- promiscuous/polygynandrous: both males and females have multiple matings (in one season)
- polygamous (includes monogamy)
i) polygyny: one male, multiple females
ii) polyandry:one female, multiple males
Gender system
- gonochoristic: fixed sex at maturation
- Hermaphroditic: sex may change
Secondary sexual characteristics
- monomorphic: no external difference between male and females
- sexual dimorphism: differences between male and females
Spawning site preparation
1.no prep
2. prep and defend site
Place of fertilization
- external
- internal
Embryonic Development
- Oviparity: develops externally
2.Ovoviviparity: birth live young, nourished by yolk sac - viviparity: birth live young, receives nourishment while in womb
Sex determination
-Major genetic factors
-Minor genetic factors
-Environmental factors
Dioecious
reproductive organs are in separate individuals
Hermaphroditism
- serial: multiple sex changes
-sequential
i) protogyny: female then male
ii) protoandry: male then female
-simultaneous: selfing and outcrossing
Functional Hermaphroditism
Monogyny:
i) monochromatic: mature females same color as juveniles
ii) dichromatic: mature females change body color to brighten terminal colors as she approaches transition to male
