Lecture 6: Evolution of Life History Strategies Flashcards
1
Q
Life history evolution
A
quantifying & explaining traits related to survival and reproduction
2
Q
Life history is comprised of:
A
- size @ birth
- age & sex at first reproduction
- frequency of reproduction
- # & size of offspring
- mortality rates & life span
3
Q
Life history strategies
A
- Links together:
1) development & growth
2) life span
3) timing & quality of reproduction - do not evolve in isolation & linked via energy trade-offs
4
Q
Survivorship curves
A
1) Type I (human, elephant)
2) Type II (robin, starling
3) Type III (barnacle, white oak)
5
Q
Intra-specific variation occurs via
A
- difference by habitat quality
- difference between sexes
6
Q
Effect on offspring fitness
A
reproductive effort influences the resource provisioning for each offspring
(ex. mean body weight per litter size & weaning/birth stage)
7
Q
Cost of reproduction for parent survival (lizard eggs example)
A
- egg removal increased survival of next reproductive event
- mediated through higher stamina & sprint speed (catching prey, avoiding predation)
- current reproduction comes at cost of future reproduction)
8
Q
Albatross example (bet hedging on jvenile survival)
A
- South GA Island: highly variable
- Kerguelen Islands: more stable environment
Which population invests more in adult survivorship/longevity?
* S. GA Island: fewer chicks/season –> adults live longer –> more opportunities for successful clutch
9
Q
Quantifying survivorship
A
- Life tables: survivorship rates
- Cohort life tables: follows individuals born same year/season from birth-death
- Static life tables: cross-section of population in a single year/season (individuals/age class)
