Specialist vs. Generalist Species
Smaller range of tolerance, or narrower ecological niche makes them more prone to extinction
What is a Specialist species?
Few offspring, heavy parental care to protect them
Usually reproduce many times
what is K-selected species?
High survivorship early in life due to high parental care
what is Type I survivorship curve species
when a population briefly exceeds carrying capacity
what is Overshoot?
Size, Density and Distribution.
what are population characteristics?
Broad food req.
High adaptability
What are Generalist Species characteristics?
Many offspring, little to no care
May reproduce only once
what are R-selected species?
High mortality (low survivorship) early in life due to little to no parental care
what is Type III survivorship curve species?
sharp decrease in pop. size when resource depletion (overshoot) leads to many individuals dying
Ex: many deer starve with too many new fawns feeding in spring
what is Die-off?
total # of individuals in a given area at a given time
Larger = safer from pop. decline
What is Size in populations?
Larger range of tolerance, broader niche makes them less prone to extinction & more likely to be invasive
What is a Generalist Species?
Long lifespan, long time to sexual maturity = low biotic potential = slow pop. growth rate
what are K-selected species?
High survivorship in mid life due to large size & defensive behavior
Rapid decrease in survivorship in late life as old age sets in
what is Type I survivorship curve species?
the max. Number of individuals in a pop. that an ecosystem can support (based on limiting resources)
what is Carrying Capacity (k)?
# of individuals/area
Ex: (12 panthers/km2)
High density = higher competition, possibility for disease outbreak, possibility of depleting food source
what is Density in populations?
Specific food requirements (bamboo)
Less ability to adapt to new conditions
What is an Specialist species characteristics?
Shorter lifespan, quick to sexual maturity = high biotic potential = high pop. growth rate
What are R-selected species?
Steadily decreasing survivorship throughout life
what is Type II survivorship curve species?
resource depletion ex: overgrazing in deer
what is the consequence of overshoot?
how individuals in pop. are spaced out compared to each other
Random (trees)
Uniform (territorial animals)
Clumped (herd/group animals)
What is Distribution in populations?
Pandas, Quetzales and Koalas.
What are specialist species?
examples of:
More likely to be invasive
Better suited for rapidly changing env. conditions
what are insects, fish and plants?
Few make it to midlife; slow, steady decline in survivorship in mid life
Even fewer make it to adulthood; slow decline in survivorship in old age
what is Type III survivorship curve species?
Hare pop. increase due to low predator pop. (lynx)
Lynx pop. increase due to increase in food (hare)
Increasing lynx pop. limits hare pop; leads to die-off
Hare die-off decreases lynx food source, leading to die-off
Hare pop. increase due to low predator pop. (lynx)
what are examples of a relationship between Predator-Prey?
Population Size =
(Immigrations + births) - (emigrations + deaths)
what is Calculating Population Change formula?