Parental Investment Flashcards
What is parental investment
All the costs that parents incur during the reproductive strategy and parental care of offspring
How do parents benefit their offspring
By using resources which results in increased numbers and survival which increases evolutionary fitness
Parental investment is greater for what sex
Female because of their investment in egg structure or uterus and gestation
Parental investment- egg cell
Has to have a large energy store which takes away from organism producing them
Parental investment- sperm
Cheap because they only pass on genetic information but needs to have no excess mass for quick movement
Life history
Organisms lifecycle
Different classifications for the trade of between quality and quantity of offspring
R selected, k selected
R selected means
Small species that produce many offspring with a low survivor rate
Reproduce earlier in life and have limited parental care
Suited in life history to rapid population growth
K selected means
Larger species and live longer, mature more slowly, produce few offspring but more than once in a lifetime, lots of parental care
Low fluctuations in population
Population curve for r selected
Exponential growth rate
Population curve for k selected
Carrying capacity
Internal fertilisation
Eggs are retained within reproductive tract of female until after they have been fertilised by sperm
External fertilisation
Both types of gametes are shed into water and the sperm swim or are carried by currents to eggs
Costs and benefits of external fertilisation
B- very large number of offspring
c- many gametes are predated or not fertilised, no or little parental care, few offspring survive
Costs and benefits of internal fertilisation
B- increase chance of successful fertilisation, less eggs needed, higher survival rate
C- mate must be located, needs direct transfer of gametes from one partner to another
