BIO 320 ECOLOGY EXAM 3 CURRENTLY TESTING QUESTIONS WITH COMPLETE
SOLUTIONS
What is age structure?
the proportion of individuals that occurs in different age classes
What do age structure pyramids with broad bases reflect?
Growing populations
What do age structure pyramids with straight sides represent?
Stable population
What do age structure pyramids with narrow bases reflect?
Declining population
What is a type I survivorship curve? and examples.
-Depicts a population with low mortality in early life and high mortality in later life
-humans, elephants, whales
What is a type II survivorship curve? and examples
- a population experience relatively constant mortality through its life
,- Squirrels, coral, and some species of songbirds
What is a type III survivorship curve? and examples..
- Depicts a population with high mortality rate in early and high survival in later life
- insects and plants
In reality which 2 types of survivor curves are most population modeled after?
Type I and Type III combined. High mortality in early and later life
What are life tables?
determine how size, age, or life history classes affect the growth of a population which
compile class-specific survival and fecundity data
What are life table typically based on?
females and fecundity (number of offspring per reproductive cycle)
What are cohort tables?
Tables are readily applied to population of plant and sessile animals in which marked
individuals can be continually tracked other the course of their entire life
What types of animals do NOT work well with cohort tables?
, Highly mobile and species with long life spans
What is an example of a problem with the cohort table?
Change in the environment during one year can affect survival and fecundity, which makes
it hard to disentangle the effects of ages vs. effects of the environment
What is a static life table?
Tables allow us to look at the survival and fecundity of all individuals during a snapshot of
time
What can static table do that cohort tables cant?
Looking at species that are highly mobile and species with long life spans
What is a major concern with using static tables? example...
Age-specific data on survival and fecundity only apply to the environmental conditions that
existed at the time the data was collected
Life table may not be representative of years where environmental conditions are ever
changing, it is help to create several maps
What is net reproductive rate?
total number of female offspring that we expect an average female to produce over the
course of her life
SOLUTIONS
What is age structure?
the proportion of individuals that occurs in different age classes
What do age structure pyramids with broad bases reflect?
Growing populations
What do age structure pyramids with straight sides represent?
Stable population
What do age structure pyramids with narrow bases reflect?
Declining population
What is a type I survivorship curve? and examples.
-Depicts a population with low mortality in early life and high mortality in later life
-humans, elephants, whales
What is a type II survivorship curve? and examples
- a population experience relatively constant mortality through its life
,- Squirrels, coral, and some species of songbirds
What is a type III survivorship curve? and examples..
- Depicts a population with high mortality rate in early and high survival in later life
- insects and plants
In reality which 2 types of survivor curves are most population modeled after?
Type I and Type III combined. High mortality in early and later life
What are life tables?
determine how size, age, or life history classes affect the growth of a population which
compile class-specific survival and fecundity data
What are life table typically based on?
females and fecundity (number of offspring per reproductive cycle)
What are cohort tables?
Tables are readily applied to population of plant and sessile animals in which marked
individuals can be continually tracked other the course of their entire life
What types of animals do NOT work well with cohort tables?
, Highly mobile and species with long life spans
What is an example of a problem with the cohort table?
Change in the environment during one year can affect survival and fecundity, which makes
it hard to disentangle the effects of ages vs. effects of the environment
What is a static life table?
Tables allow us to look at the survival and fecundity of all individuals during a snapshot of
time
What can static table do that cohort tables cant?
Looking at species that are highly mobile and species with long life spans
What is a major concern with using static tables? example...
Age-specific data on survival and fecundity only apply to the environmental conditions that
existed at the time the data was collected
Life table may not be representative of years where environmental conditions are ever
changing, it is help to create several maps
What is net reproductive rate?
total number of female offspring that we expect an average female to produce over the
course of her life
