The evolution of parental care, Lecture 9 Flashcards
Reproduction is costly
two costs:
- mating effort
2. parental effort
Mating effort includes
6
- terroritory defence
- mate attraction
- female defence
- flower production
- nuptial gifts
- mate guarding effort
Parental effort includes
2
- investment in gametes
2. parental care
The allocation of costs is a …
trade off
Can the balance of parental care vs mating effort vary within species?
yes, eg: between males and females
Trade off:
no. of young vs….
effort of care
Investement in gametes
there tends to be few large offspring or many small ones
Parental care
2 aspects
- variety of parental care
2. costs of parental care
Two costs of parental care
environmental effects
individual differences
Parental investment
Resources allocated from parent to offspring which increase offspring viability at a cost to the parent
Two more costs of parental care
direct costs - energy and resources
lost future reproductive opportunities
Is parental care hard labour?
yes,
How much effort is ‘hard labour’
takes up energy of 4x basal metabolic rate
Costs of incubation
can’t feed whilst incubating which leads to weight loss,
use extra body heat to the egg
Which birds lay one egg per day are an example that other resources aren’t always limiting?
wrynecks,
they lay on egg per day and stop when they feel a full clutch
removals can induce them to lay up to 76 eggs - so materials aren’t limiting in this case
