Sex and Behaviour Flashcards
Which sex gives more investment in gamete production?
Females.
What is the benefit of parental investment?
It increases the probability of production and survival of young.
What are the characteristics of r-selected species?
Smaller, short generation time, mature rapidly, reproduce early, produce large number of small offspring, limited parental care.
What are the characteristics of k-selected species?
Larger, live longer, mature slowly, reproduce many times, produce fewer large offspring, high level of parental care.
Where does r-selection occur?
In unstable environments where the species has not reached its reproductive capacity.
Where does k-selection occur?
In stable environments.
What are the benefits of external fertilisation?
There is a very large numbers of offspring
can be produced.
What are the costs of external fertilisation?
Many gametes are predated or not fertilised, no or limited parental care and few offspring survive.
What are the benefits of internal fertilisation?
Increased chance of fertilisation, fewer eggs needed, offspring retained internally for protection and development., higher offspring survival rate.
What are the costs of internal fertilisation?
A mate must be located which requires energy expenditure, requires direct transfer of gametes from one partner to another,
What is monogamy?
The mating of a pair of animals to the exclusion of all others.
What is polygamy?
Individuals of one sex have more than one mate.
What is polygyny?
One male mates exclusively with a group of females.
What is polyandry?
One female mates with a number of males in the same breeding season.
What does sexual selection select for?
Characteristics that have little survival benefit for the individual but increase their chance of mating.
