lecture 14

Question 1

what can age structure in a population influence?

Answer 1

per capita rates (i, e, b, d)

Question 2

what can stage structure influence in a population?

Answer 2

individuals in different stages can have different vital rates

Question 3

how does the sex structure influence populations?

Answer 3

males and females may have different per capita rates

Question 4

what is demography?

Answer 4

the branch of population biology dealing with population projections for age-structured populations

Question 5

what are the two important factors when examining age, structure, populations?

Answer 5

1. survivorship
2. reproduction

Question 6

what is survivorship?

Answer 6

the pattern of survival for individuals in a population as a function of age

Question 7

what are the three patterns of survivorship curves?

Answer 7

1. type I - decreasing survival
2. type 2 - constant survival
3. type 3 - low initial survival

Question 8

what is the type 1 survivorship pattern?

Answer 8

juvenile survival rate is high and most mortality occurs among older individuals

Question 9

what is the type 2 survivalship pattern?

Answer 9

individuals die at equal rates, regardless of age

Question 10

what is the type 3 survivorship pattern?

Answer 10

individuals die at a high rate as juveniles and then at much lower rates later in life

Question 11

whats a fecundity schedule?

Answer 11

the avergae number of offspring produced for each age per female

Question 12

what are life tables?

Answer 12

tables that combine the survivorship and fecundity schedules and can be used to estimate the next reproductive rate

Question 13

if a life table is using a species with 2 sexes which do we follow?

Answer 13

the female

Question 14

what is a stable age distribution?

Answer 14

the proportion of individuals in each age class is constant

Question 15

how is a stable age distribution reached?

Answer 15

if the life table values are fixed

Question 16

why do we use stage structured populations?

Answer 16

• sometimes we dont need to consider each age because a series of ages are similar in their vitao rates
• so stage is more important for population growth rates

Question 17

what are stage structured models used for?

Answer 17

conservation/management

Question 18

how are stage structured models depicted?

Answer 18

with a life cycle diagram

Question 19

how can a stage structured life table be used?

Answer 19

to identify which stage if an organisms life cycle is most important