Chapter 8: Life histories

Question 1

Life history

Answer 1

schedule of organism’s growth, development, reproduction, survival
- combined effect of morphology, behavior, and anatomy and how they interact/are affect by the environment
- solution to the problem of allocating limited time and resources for maximum reproductive solution

Question 2

on average ___ offspring produced by an individual will live to reproduce

Answer 2

only 1

Question 3

2 variations in life history:

Answer 3

• Vary w/ respect to life form, habitat, or environment
• Vary w/ variation in other life histories

Question 4

Slow life history

Answer 4

require a long time to reach sexual maturity
- Long life span, low # of offspring, high parental investment

Question 5

Fast life history

Answer 5

short times to sexual maturity
- short life span, high # of offspring, little parental investment

Question 6

fecundity

Answer 6

number of offspring produced by an organism per reproductive episode

Question 7

parity

Answer 7

number of reproductive episodes an organisms experiences

Question 8

parental investment

Answer 8

amnt of time and energy given to offspring by parents

Question 9

longevity

Answer 9

life span; life expectancy

Question 10

vegetative reproduction

Answer 10

asexual reproduction in plants (grow off existing plants)

Question 11

Principle of allocation

Answer 11

observation when resources are devoted to 1 body structure, physiological function, or behavior, they can’t be allotted to another

Question 12

Number of offspring vs. size trade-off ex:

Answer 12

making more seeds/offspring makes the seeds smaller

Question 13

Number of offspring vs parental care trade-off ex:

Answer 13

more offspring at 1 event = less parental care available for each

Question 14

parents have the greatest fitness when their offspring are ____ size

Answer 14

small/intermediate size

Question 15

Determinate growth

Answer 15

growth pattern in which an individual doesn’t grow after beginning reproduction

Question 16

Indeterminate growth

Answer 16

growth pattern in which an individual continues to grow after beginning reproduction

Question 17

Fecundity

Answer 17

ability to produce abundance of offspring

Question 18

Senescence

Answer 18

gradual decreases in fecundity w/ increase in probability of mortality
- ex: humans

Question 19

Stimuli for change:

Answer 19

• seasonal changes
• risks of predation
• global warming

Question 20

k selected populations: humans (gorrillas, chimps, etc.):

Answer 20

stable environment, large, less offspring; survivor curve type 1
- high maturation rate
- long lifespan
- low pre-reproductive mortality
- low clutch size (1 baby at a time)
- low reproduction rates
- high parental/postnatal care

Question 21

R-selected (opportunistic) populations:

Answer 21

unstable environments, small; have lots of babies, not all survive; survivor curve type 3
- high maturation rate
- short lifespan
- high pre-reproductive mortality
- high clutch size (many babies at 1 time)
- high reproduction rates
- low parental care

Question 22

Reproductive strategy

Answer 22

ways in which a species ensures its offspring reach adulthood
- R strategy and K strategy
- All animals fall along continuum

Question 23

gonads

Answer 23

primary sexual organs in animals

Question 24

distribution of parental chromosomes into haploid cells is…

Answer 24

randomly distributed
- mixing results in new combinations

Question 25

self-fertilization vs out-crossing in hermaphrodites

Answer 25

self-fertilization: individuals male and female gametes fertilize each other (simultaneous)
out-crossing: individuals breed w/ each other w/ one or other; deduces inbreeding depression (sequential)