life histories

Question 1

3 goals of every individual in life

Answer 1

1. consumer resources and grow to maturity
2. avoid being killed
3. reproduce (successful offspring)

Question 2

fecundity

Answer 2

the number of offspring produced by an organism per reproductive episode

Question 3

parity

Answer 3

the number of reproductive episodes an organism experiences

Question 4

parental investment

Answer 4

the time and energy given to an offspring by its parents

Question 5

longevity (life expectancy)

Answer 5

the life span of an organism

Question 6

“slow” life history

Answer 6

-long time to sexual maturity
-long life spans
-low numbers of offspring
-high parental investment
(elephants, oak trees)

Question 7

“fast” life history

Answer 7

-short time to sexual maturity
-short life spans
-high numbers of offspring
-little parental investment
(fruit flies, weeds)

Question 8

stress tolerators

Answer 8

typically small herbs with a long life span, slow growth, and a long time to sexual maturity

Question 9

competitors

Answer 9

grow fast, achieve early sexual maturity, and devote little energy to seed production

Question 10

ruderals

Answer 10

grow fast and devote a high proportion of their energy to reproduction

Question 11

principle of allocation

Answer 11

the observation that when resources are devoted to one body structure, physiological function, or behavior, they cannot be allotted to another
-natural selection will favor individuals that allocate resources optimally (maximum fitness)

Question 12

as the number of offspring increases

Answer 12

the amount of parental care per offspring will decrease
-reduces chance of offspring survival

Question 13

having more offspring makes parents work hard to feed more young which results in

Answer 13

decreased parental survival

Question 14

determinate growth

Answer 14

a growth pattern in which an individual does not grow any more once it initiates reproduction
-occurs in many species of birds and mammals

Question 15

indeterminate growth

Answer 15

a growth pattern in which an individual continues to grow after it initiates reproduction
-occurs in many species of plants, invertebrates, fish, reptiles, and amphibians

Question 16

organisms with a long life span favor

Answer 16

determinate growth
-allows them to grow first and reproduce later

Question 17

organisms with a short life span favor

Answer 17

indeterminate growth
-allows them to quickly reproduce before death

Question 18

low predation

Answer 18

-higher adult size
-higher embryo weight
-fewer offspring

Question 19

high predation

Answer 19

-lower adult size
-lower embryo weight
-more offspring

Question 20

semelparous

Answer 20

-breed once in lifetime
-store resources for one reproduction
-programmed death after reproduction
-arises when there is a massive amount of energy required for reproduction
-common in insects and plants

Question 21

iteroparous

Answer 21

-breed multiple times
-more common
-common among birds, reptiles, mammals, and amphibians

Question 22

annual

Answer 22

an organism that has a life span of one year

Question 23

perennial

Answer 23

an organism that has a life span of more than one year

Question 24

senescence

Answer 24

a gradual decrease in fecundity and an increase in the probability of mortality
-inevitable consequence of natural wear and tear

Question 25

photoperiod

Answer 25

the amount of light that occurs each day
-provides a cue for many events in the life histories of virtually all organisms

Question 26

often determines the timing of life history events

Answer 26

-fluctuations in resource ability
-predation
-global warming
-human activity

Question 27

low food

Answer 27

-later age of metamorphosis
-smaller adult frogs

Question 28

high food

Answer 28

-earlier age of metamorphosis
-larger adult frogs

Question 29

problems can arise when a species depend on

Answer 29

the environment to provide the necessary resources with an altered breeding season