Chapter 51-Pop Ecology

Question 1

population

Answer 1

group of individuals from the same species that live in the same area at the same time

Question 2

Distribution and abundance

ex:Zootoca vivipara lizard

Answer 2

common resident from Ireland in western Europe to Japan in eastern Asia, but can live in many habitats and is cold adapted
Zooming into a local scale, the lizard’s distribution is clumped according to where there is suitable habitat

Question 3

Population density

Answer 3

number of individuals per unit area - varies throughout the range

Question 4

Random Distributions

Answer 4

if the position of each individual is independent of the others

Question 5

Clumped Distributions

Answer 5

patchy habitat or the organisms are social

Question 6

Uniform Distributions

Answer 6

if organisms have negative interactions that space them evenly

Question 7

If a species range is small…

Answer 7

it may consist of a single population of interbreeding individuals

Question 8

If a range is large….

Answer 8

may consist of many populations—sometimes contiguous, and sometimes isolated in space

Question 9

metapopulation

Answer 9

population of populations connected by migration

-when suitable environments are scattered

Question 10

Mark–recapture

Answer 10

1: catch individuals and mark them (leg bands, ear tags, etc)
2: release marked animals and allow them to mix well with the unmarked ones in the population
3: catch individuals again - the percentage of marked individuals that were recaptured is recorded
4: marked/total?= marked recaptured/recaptured total

Question 11

Mark–Recapture assumption (5)

Answer 11

–Individuals are not moving in and out of the study area.
–Individuals mix between captures.
–No bias exists regarding which individuals are caught in each recapture.
–Individuals do not learn to avoid or seek out traps after being caught once.
–Individuals do not change their behaviour, attract and/or deter predators or mates, or die from being handled

Question 12

Age structure

Answer 12

number of individuals of each age

Question 13

To predict the future size of a population, you need to know:

Answer 13

–Age structure
–Number of individuals of each age likely to survive to the following year
–Number of offspring produced by females of each age
–How many individuals of different ages immigrate and emigrate each generation
–The average time between a mother’s first offspring and that of her daughter (generation length)

Question 14

If a population consists of mostly young individuals with high survival and reproductive rates….

Answer 14

should increase

Question 15

If a population consists of mostly old individuals with low survival and reproductive rates

Answer 15

should decrease

Question 16

life table

Answer 16

probability that an individual will survive and reproduce in any given time interval over the course of its lifetime

Question 17

Age class

Answer 17

individuals of a specific age

Question 18

cohort

Answer 18

group of individuals of the same age that can be followed through time

Question 19

Survivorship

Answer 19

proportion of offspring that survive, on average, to a particular age

Question 20

Survivorship curve

Answer 20

plot of the logarithm of the number of survivors versus age

Question 21

EX: Tyrannosaur Albertosaurus sarcophagus

Answer 21

Had a modified Type II survivorship curve, with low juvenile mortality and increased mortality at reproductive maturity

Question 22

per capita rate of increase (r)

Answer 22

The difference between the birthrate and death rate per individual

Question 23

Intrinsic rate of increase, rmax

Answer 23

r is at a maximum when b (birth) is at a maximum and d (death) is at the minimum

Question 24

Exp growth occurs when…

Answer 24

r is constant

Question 25

Exp growth is density dependent. Why?

Answer 25

Because population size does not limit growth rate. Exponential growth cannot continue indefinitely, resources are finite and will eventually run out

Question 26

carrying capacity, K

Answer 26

A population hits its upper limit and switches to logistic growth pattern

Question 27

Logistic growth is dependent on

Answer 27

pop size

Question 28

What factors limit population size?

Answer 28

Density-independent factors: weather patterns, are usually abiotic; they change birthrates and death rates irrespective of population size

Density-dependent factors: depend on population size and decrease fecundity or survivorship

Question 29

metapopulation

Answer 29

collection of populations interacting via dispersal

Question 30

Pop momentum

Answer 30

• In developing countries, overall population size will increase dramatically over the course of your lifetime
• Part of this increase will be due to increased survivorship
• A paradox – although an average fecundity has decreased, these populations also now have more young women and thus higher m

Question 31

zero population growth (ZPG)

Answer 31

When fertility at the replacement rate is sustained for a generation
(each woman producing exactly enough offspring to replace herself and her offspring’s father)

Question 32

The role of fertility rates on pop

Answer 32

Influenced by:
–How much access women have to education and reliable birth control methods
–Overall economic development
–Access to quality health care

Question 33

Endangered Species survivorship and fecundity

Answer 33

high juvenile mortality, low adult mortality, and low fecundity

–In these species, the fate of a population is sensitive to increases in adult mortality.
–Conservationists can then focus resources on protecting adults rather than eggs or juveniles

Question 34

The populations within a larger metapopulation are most likely to survive when:

Answer 34

1. Have larger population size
2. Occupy larger geographical areas
3. Are closer to neighbouring populations
4. Have higher genetically diversity

Question 35

Fecundity

Answer 35

# of female offspring produced by each female in pop 
OR age specific fecundity: specific to each age class of females

Question 36

Factors that limit pop size:

Answer 36

Density-independent: weather, hurricanes, drought, etc.

Density-dependent: survivorship, fecundity

Question 37

K varies…

Answer 37

• for different species because some habitats better due to food availability, space, etc
• in time because conditions may be better depending on the season/year