population ecology

Question 1

what is ecology?

Answer 1

study levels of organization ranging from individuals organisms to the biosphere
study of the interactions between organisms and their environments

Question 2

what do the mathematical models do?

Answer 2

allow computer models to simulate natural events and large scale experiments

Question 3

what are the steps in Mark-Recapture study?

Answer 3

1. capture a random sample of individuals that are marked
2. release marked individuals back into population
3. capture a second random sample if individuals, some of whom are marked
4. calculate initial population size using the formula n1/x=n2m/n2

Question 4

what is geographical range?

Answer 4

overall spatial boundaries within which a population lives

Question 5

what is a habitat?

Answer 5

specific environment in which a population live as characterized by its biotic and abiotic features

Question 6

what is spatial distribution?

Answer 6

individuals within the geographical range
doesn’t tell the population

Question 7

what is dispersion patterns influenced by?

Answer 7

distribution of resources in environment/ landscape
habitat requirements of each individual
social structure of species
dispersal capacity of reproduction of species
presence of other species

Question 8

what is random distribution?

Answer 8

distance between individuals is random with respects to each other’s location
rarest type of destitution
found in homogeneous environments

Question 9

what is uniform distribution?

Answer 9

maximal distance between and two individuals
- found in many lants due to competition for resources
- also can result from territorial behaviour

Question 10

what is a clumped distribution?

Answer 10

most common form of distribution
- resources rare
- poor dispersal capacity
- benefits to group living

Question 11

what are population characteristics?

Answer 11

population age structure
sex ratio
proportion reproduction
generation time
can have dramatic effects on capacity for future growth

Question 12

what is demography?

Answer 12

statistical study of processes that change a population’s size and density through time

Question 13

what is a life table?

Answer 13

summarize demographics of a population

Question 14

what are the different types of survivorship curves?

Answer 14

type 1: high survivorship until late life
type 2: constant rate of mortality in all ages classes
type 3: high juvenile mortality, followed by low mortality after critical age and size

Question 15

what is life histories?

Answer 15

the schedule frequency and duration of events in an organisms’ lifetime

Question 16

what is the evolution of life histories?

Answer 16

influenced by organism’s physical and ecological environment
- development age
- age of sexual maturity
- number of offspring
- level of parenting investment
- senescence and death

Question 17

what is passive parental care?

Answer 17

before offspring born

Question 18

what is active parental care?

Answer 18

offspring is born
many young = little care
few young = more care

Question 19

what are the 2 types of breeding?

Answer 19

semelparity
iteroparity

Question 20

what is semelarity?

Answer 20

one reproductive episode
devotes all stored energy
maximal fecundity
death after reproduction

Question 21

what is iteroparity?

Answer 21

multiple reproductive episodes
only some energy devoted in each even

Question 22

what does early reproduction favor?

Answer 22

adult survival rates low
animals do not grow more fecund with age

Question 23

what does later reproduction?

Answer 23

if sexually mature adults likely to become older
if organisms grow larger with age
if larger organisms have higher fecundity
can have more offspring, natural selection favours this

Question 24

what is life history evolution?

Answer 24

trade offs reflect differences strategies to maximize fitness

Question 25

what is LH characteristic 1?

Answer 25

male displays probability of being predated increases brightness/ number of spots attractiveness vs survival tradeoff

Question 26

what is LH character 2?

Answer 26

body size probability of being predated decrease with body size effect on time for first reproduction

Question 27

what is LH character 3?

Answer 27

many stimuli offspring, produce more frequently vs. fewer better provisioned offspring produce more occasionally

Question 28

what is LH character 4?

Answer 28

trade-off for parasite tolerance

Question 28

life history traits and population?

Answer 28

the specific of a species life history characteristics can have important consequences for - population growth - population fluctuations - nature of interactions with other species

Question 29

what is population growth?

Answer 29

organisms often have the capacity to produce more offspring than are needed to replace themselves in the next generation the study of population growth is central to ecology

Question 30

what is the exponential growth model

Answer 30

by expressing per capita birth and death rates, education describes unlimited population growth when there is no limits on population growth, it follows exponential pattern

Question 31

what is rMAX?

Answer 31

intrinsic rate of increase (maximum per capita growth rate) fast maturation = high rMAX more offspring = high rMAX

Question 32

what is bacterial population growth?

Answer 32

bacteria reproduction by binary fission; their population in size each generation - short generation time - small body size - large rMAX

Question 33

what is the logistical growth model?

Answer 33

most population growth is not exponential - limited in some fashion carrying capacity (K): maximum population size that environment can sustain (theoretical but not fixed value) per capita population growth rate (r) decrease in N approached K

Question 34

what are the prediction effects of N on r?

Answer 34

when N < K, r > 0 when N = K, r = 0 when N > K, r < 0

Question 35

what is density dependent factor?

Answer 35

crowding decreases individual growth rates, adult size and survivorship

Question 36

what is fecundity is density dependent

Answer 36

more competition between species in same environment

Question 37

what are density dependent factors?

Answer 37

reduced population growth regardless of population size

Question 38

what are density independent factors?

Answer 38

may interact with density dependent factors - food shortage caused by high population density may lead - malnourished individual may be more likely to succumb to stress of extreme weather

Question 39

what is cyclic fluctuations?

Answer 39

some animal populations exhibit cyclic fluctuation in size

Question 40

what is intrinsic control?

Answer 40

hormonal and behavioural changes

Question 41

what is extrinsic control?

Answer 41

relationships between a cycling species and other factors (food or predators)