chapter 5

Question 1

Exponental growth model

Answer 1

Exponential growth
dN/dt=rN
Key:
N = population density
T = time
R = per capita growth rate

Question 2

logistic growth model

Answer 2

dN/dt=rN(K-N)/K

N = population density
T = time
R = per capita growth rate
K = carrying capacity

Question 3

Populations

Answer 3

A group of individuals of one species in an area

Question 4

Unitary organisms

Answer 4

Those that proceed by a determinate pathway of development of a tightly canalized adult form.

Question 5

Modular organisms

Answer 5

Those that grows by the repeated iteration of parts

Question 6

Genet

Answer 6

Genetic individual - The organism developed from a zygote.

Question 7

Module

Answer 7

An offshoot formed by vegetative growth in modular organisms that is actually or potentially independent physiologically

Question 8

Abundance

Answer 8

The number of individuals in a population may be obtained by
Census: counting all individuals
Complete
Sample plots
Sampling: counting an known fraction to arrive at an estimate of total number

Question 9

census examples

Answer 9

aerial photography
thermography
radar
Line transects/quadrat sampling: Involves observing (both sight and sound) individuals within an area of known or estimated size

Question 10

Mark-recapture method

Answer 10

On a first visit to a population of unknown total size N, a representative sample is caught (r individuals) and given a harmless mark

These are released back into the population, where they remix with the unknown number of unmarked individuals

On a second visit, a further representative sample (n) is caught, and the number of marked individuals (m) is counted
r/N=m/n, therefore N=r*n/m

Question 11

Life cycles

Answer 11

juvenile phase dominated by growth, onset of reproduction, end of reproduction/death or after that the postreproductive phase e.g. orcas then death

Question 12

Iteroparous species

Answer 12

repeated breeding cycles / continuous breeding.
resources are set aside for survival to further breeding episodes
e.g.
humans
birds
crickets

Question 13

Semelparous species

Answer 13

single reproductive episode after which they die.
All resources are devoted to breeding and none to survival
e.g
salmon

Question 14

Cohort life table, Monitoring birth and death

Answer 14

data are collected by following a cohort throughout its life

Question 15

Static life table, Monitoring birth and death

Answer 15

age-distribution data are collected from a cross-section of the population at one particular time

Question 16

Spatial distribution of organisms

Answer 16

Perception of pattern depends on the spatial scale
The density perception of individual organisms determines behaviour
e.g.
Urban white-tail deer in Illinois often reach extreme population levels
Reproduction in these deer is density-dependent (low density -> high reproduction)

Question 17

Intraspecific competition

Answer 17

Competition between individuals of the same species

Intraspecific competition reduces birth rate and increases mortality per individual
These effects are density-dependent
When birth rate = mortality, the population remains stable

Question 18

Interspecific competition

Answer 18

Competition between individuals of different species

Question 19

Carrying capacity (K), Intraspecific competition

Answer 19

The maximum population size that can be supported indefinitely by a given environment, at which intraspecific competition has reduced the per capita net rate of increase to zero.

Question 20

Life history patterns

Answer 20

For most organisms, there is a trade-off between growth and reproduction
e.g. butterflies females put energy/resources into parenting and males into mating

Question 21

Trade-off #1, life history patterns

Answer 21

Trade-off #1: An organism has to divide its energy between growth and reproduction

Question 22

Trade-off #2, life history patterns

Answer 22

Trade-off #2: Fitness of offspring is generally inversely related to number of offspring

Question 23

r-strategy, Life history patterns

Answer 23

resources assigned to reproduction
produce as much offspring as fast as possible
Most usefull in uncertain environment
Population far below carrying capacity

high mortality rate. Resources assigned to fast reproduction rate, without investing too much energy in developing a long-lived body that will in practice be killed long before the limit age

Question 24

K-strategy, Life history patterns

Answer 24

invest resources in a long term development and long life
Most usefull in stable environment
Population near carrying capacity
Competition and resource limitation

low mortality rate. Resources assigned to a defense mechanism (shell) and efficient repair mechanisms that allow it to live long

Question 25

Photoperiod

Answer 25

Length of the period of daylight each day

Question 26

Unitary

Answer 26

Unitary organisms are organisms that proceed by a determinate pathway of development of a tightly canalized adult form, e.g. all arthropods and vertebrates. The contrast is with modular organisms in which growth occurs by the indeterminate iteration of repeated units of structure (modules).

Question 27

Static

Answer 27

A static life table is a life table that is constructed from the age structure of a population at a single moment in time

Question 28

Ephemeral

Answer 28

Ephemeral organisms are organisms with a short life cycle, especially plants whose seeds germinate, grow to produce new seeds, and then die all in a short period, often less than 8 weeks.

Question 29

Ramet

Answer 29

An offshoot formed by vegetative growth in modular organisms that is actually or potentially physiologically independent.

Question 30

Stoloniferous

Answer 30

Stoloniferous organisms are modular organisms in which colonies spread laterally and remain joined by "stolons."

Question 31

Annual

Answer 31

A species with a life cycle which takes approximately 12 months or rather less to complete, whose life cycle is therefore directly related to the annual cycle of weather, and whose generations are therefore discrete.

Question 32

Survivorship curve

Answer 32

A survivorship curve is a plot of the declining size of a cohort, or presumed cohort, as the individuals die, usually with time on the horizontal axis and log₁₀ lₓ on the vertical axis (where lₓ is the proportion of the original cohort still alive)

Question 33

Cohort

Answer 33

All individuals born within a particular period

Question 34

Genet

Answer 34

The organism developed from a zygote. The term is used especially for modular organisms and members of a clone to define the genetic individual and to contrast with ‘ramet,’ the potentially physiologically independent part that may arise from the iterative process by which modular organisms grow

Question 35

Fledgling

Answer 35

A young bird which has just developed its flight feathers and is about to leave the nest.

Question 36

Perennial

Answer 36

An organism that lives for several years

Question 37

Intraspecific

Answer 37

Intraspecific competition is competition between members of the same species.

Question 38

Iteroparous

Answer 38

Iteroparous species are species that breed repeatedly, devoting some of their resources during a breeding period not to breeding itself, but to survival to further breeding episodes.

Question 39

Modular

Answer 39

Modular organisms are organisms that grow by the repeated production of "modules" such as leaves, coral polyps, etc.

Question 40

Dispersal

Answer 40

The spreading of individuals away from each other, e.g., of offspring from their parents and from regions of high density to regions of lower density.