Lecture 13- Parental care and investment

Question 1

parental care

Answer 1

parental traits which enhance the fitness of their offspring, which is likely to exist predominantly for this function

Question 2

parental expenditure

Answer 2

expenditure of resources for the care of offspring

Question 2

parental investment

Answer 2

any investment that increases the chance of future offspring’s survival at the cost of investing in other offspring

Question 3

parental effort

Answer 3

combined fitness costs incurred due to the production and care of offspring in a particular period, such as a breeding season

Question 4

parental effect

Answer 4

causal effects of a parent’s phenotype on the offspring’s phenotype (above inherited traits)

Question 5

example of preparatory investment

Answer 5

nests produced during reproduction

Question 6

2 examples of pre-birth provisioning

Answer 6

producing large eggs, e.g. kiwi birds, or seeds, e.g. daffodil bulbs
viviparity- producing well-developed offspring, e.g. giraffes being able to walk quickly after birth

Question 7

example of parental care without provisioning

Answer 7

lacebugs- protection of young from predation, can see quite strong ‘instincts’ e.g. returning to nest from up to 30m

Question 8

mass vs continuous provisioning

Answer 8

mass- bringing back food in big chunks, often seen in smaller animals
continuous- e.g. birds- repeatedly bringing food back to young

Question 9

examples of some contributing factor to parental care

Answer 9

life history traits
environmental conditions
ability to provide care
extent of fitness benefits
ability of parental care mutant genes to spread

Question 10

example of biparental care in frogs

Answer 10

male watching over tadpoles, females respond to calls that they are hungry

Question 11

examples of shifting costs/benefits of parental care

Answer 11

male desertion seems to happen more when there is a female bias in a species of fish, as investment is more beneficial elsewhere

Question 12

example of how parental care differs between taxa

Answer 12

uncommon in invertebrates, biparental and male-only care even more uncommon
90% biparental care in birds
female care in all species- nature of mammals- some cases of biparental care
more male-only in fish

Question 13

why is it hypothesised that there is so much male-only care in fish

Answer 13

possibly less opportunity cost of male care compared to female

Question 14

example of ‘bad care’ in fish

Answer 14

eating of eggs, possibly if they are perceived as ‘bad’ to avoid investing in unviable offspring

Question 15

‘bad care’ in birds

Answer 15

tits abandoning offspring, hiding eggs, pretending to have more eggs etc to get partners to stay
favouritism, especially in unpredictable environments where optimism may lead to more eggs than are viable being produced