Stabilizing, Disruptive, or Directional?
A plant that is too short may not be able to compete with other plants for sunlight. However, extremely tall plants may be more susceptible to wind damage. Combined, these two selection pressures select to maintain plants of medium height. The number of plants of medium height will increase while the numbers of short and tall plants will decrease.
What is Stabilizing
stabilizing, disruptive, and directional selection.
Define Adaptation
Traits that allow a species to survive in its environment
Stabilizing, Disruptive, or Directional?
Using the familiar example of giraffe necks, there was a selection pressure against short necks, since individuals with short necks could not reach as many leaves on which to feed. As a result, the distribution of neck length shifted to favor individuals with long necks.
What is Directional
Define Tolerance Limit
are the upper and lower limits of environmental factors (like temperature, salinity, or sunlight) within which an organism can survive and reproduce
This defense adaptation releases a bad smell to scare predators.
What is chemical defense / skunk spray?
Stabilizing, Disruptive, or Directional?
A field contains black and white rocks. Grey rabbits cannot blend in behind the rocks while black and white rabbits can hide from predators.
What is disruptive
Define Ecological Niche.
is the role a species plays in its environment
and the conditions it needs to live and survive there.
Arctic animals often have this adaptation to blend in with the snow.
white coloration or camouflage
Stabilizing, Directional, or Disruptive?
Human babies that are born too early are often a light birth weight and can't survive outside of the womb. Human babies born late are usually large and tough for mom to deliver. Therefore, an average human birth weight is best.
What is stabilizing
Define Allopatric Speciation
new species arise due to geographic isolation.
When two species evolve together and each influences the other’s adaptations, this process is happening.
Coevolution.