lecture 21

Question 1

populations

Answer 1

groups of interbreeding individuals of the same species living in the same general area

Question 2

population ecology

Answer 2

the study of births deaths and dynamic forces that regulate a population

Question 3

what are the two ways to describe populations

Answer 3

spatial and temporal

Question 4

density

Answer 4

the number of individuals per unit area on volume

Question 5

dispersion

Answer 5

pattern of spacing within population boundaries

Question 6

how to measure density

Answer 6

you can count individuals in a small area or count the signs of individuals (tracks, feces)

Question 7

how to measure animals that move

Answer 7

mark recapture methods , 1. capture 2. mark. 3.recapture 4. do math

Question 8

formula for CMR

Answer 8

number of animals marked on day one times the number of animals captured at day two all divided by the number of marked found in the second capture

Question 9

question: captured 10 gerbils and second day you get 1000 and only five are marked , calculate

Answer 9

(10x1000)/5

Question 10

what are the three main dispersion patterns

Answer 10

clumped, random, uniform

Question 11

clumped

Answer 11

social patterns or resource distribution (common)

Question 12

random

Answer 12

wind dispersion (less common)

Question 13

uniform

Answer 13

allelopathy (plants secret toxins), competition, territoriality

Question 14

temporal populations

Answer 14

pop changes over time, birth and death rates

Question 15

demography

Answer 15

study of process that influence birth, death, population growth rates.

Question 16

life history

Answer 16

traits that make up schedule of reproduction (age at first reproduction, frequency and duration, total of offspring)

Question 17

life history trade offs

Answer 17

cannot invest in all traits simultaneously

Question 18

principal of allocation

Answer 18

resources need to be directed among competing life functions

Question 19

what resource has to be met first prior to everything else (in typical conditions, normal resources)

Answer 19

maintenance

Question 20

how are resources divided in typical conditions and abundant resources

Answer 20

more resources are gained and more are available after maintenance needs are met

Question 21

how are resources divided in stressful conditions and normal resources

Answer 21

this means more resources must be expended on maintenance and fewer are available for other purposes

Question 22

semelparous species

Answer 22

they expend their energy inn a single immense reproductive effort (many insects, and annual plants do this)

Question 23

iteroparous species

Answer 23

they exhibit repeated reproductive cycles

Question 24

what are the three main patterns of survivorship

Answer 24

type 1 (humans) type 2 (birds) type 3 (trees)

Question 25

type 1

Answer 25

they have more offspring surviving in the beginning of their lives but they decline as time pass by (they dont live over 90) graph is exponential but backwards

Question 26

type 2

Answer 26

they have decent survivorship and many grow old so graph is linear

Question 27

type 3

Answer 27

less off spring survive but they live til forever opposite of type 1 graph

Question 28

BD model

Answer 28

birth death model, population at future time depends on current population size plus births and deaths in that time interval

Question 29

BD equation

Answer 29

change in population size over change in time equals B-D

Question 30

per capita population growth is

Answer 30

expressed on a per individual basis

Question 31

per capita birth rate is

Answer 31

b= avg number of offspring produced

Question 32

per capita death rate is

Answer 32

d= avg individual chance of dying

Question 33

birth rate and death rate equation

Answer 33

B= b times N or b=B/N and D= d times N or d= D/N

Question 34

per capita rate of increase

Answer 34

r= b-d so r > 0 is increasing and r < 0 is decreasing

Question 35

the exponential model

Answer 35

describes population growth in an idealized environment (ex. unlimited resources, no competition)

Question 36

what term are we using when resources are unlimited

Answer 36

r max

Question 37

what shape does the exponential growth graph show

Answer 37

j shaped