Exam 9: From Populations to Communities

The tendency of a population to decrease in size when it is above a certain level,but to increase in size when it is below that level describes how abundance is _________________ ?

Which of the following might be considered primary succession:

When the order of colonization impacts competitive outcomes:

Which of the following terms is used to define a collection of subpopulations that can go extinct and appear again through recolonization?

In founder-controlled communities:

You review successional data,which show a subset of plants colonizing a gap in the following order: Common chickweed (annual)-> salvias (herbaceous perennial shrub)-> toyon (woody perennial shrub).Using these data,does it appear that plants are following a typical sequence of dominant vegetation? If so,which species might follow?

In what type of community are species approximately equivalent in their ability to invade gaps and hold those gaps against other species during their lifetime?

Which of the following is an example of a trophic cascade?

When one studies metapopulations the following can occur:

Which of the following might be best explained by a trophic cascade?

If the numbers of a predatory Orca whale can determine the abundances of an abalone despite the fact that Orcas don't prey on abalone we would call that a/an ________

In 1944,a researcher observes 710 ithomiine butterflies in a lek in a Central American rainforest.In 1945,1946,and 1947,the same researcher observed 722,711,744,and 702 individuals in a lek at the same location.In 2012,a different researcher revisited the same location and observed 694 ithomiine butterflies in the lek.What can you say about the stability of these ithomiine butterflies?

The connection between food web complexity and stability is more complex than once thought.Currently we think that populations are actually _________ stable when the web is complex and the aggregate whole community might be _________ stable when the web is complex.

What term describes structured analyses that use large numbers of data sets to discern consistent trends?

You have researched outbreaks of West Nile virus.You see a pattern whereby the numbers of incidences of outbreaks increases ten days after a period of precipitation in which daily temperature is below 20 degrees Celsius,soil moisture is between 50% to 65%,and relative humidity is above 60% over a continuous period of 5 days.What can you conclude from these data?

An island is newly formed by a volcanic eruption.You want to follow what happens with plant communities on the island.What type of succession is this?

All keystone species are predators.Is this accurate?

Any species that has a low abundance but exerts strong effects upon the community through multiple trophic levels would be considered which of the following?

If one were to plot species numbers in a community after a disturbance over a long time period

Beavers build dams that create flooding that creates abundant aquatic habitat.They might be considered ______________?