Exam 4: Populations and Communities

Some beetles escape from a ship and fly to a small island covered with grass but with no trees or beetle predators.As the beetles feed,they destroy all the grasses.But with abundant food,the beetle population soars,doubling in size every month.After about a year,the population crashes as thousands of beetles have destroyed almost all of the plants and there is little left to feed the large population.This scenario best illustrates

In a mature forest in a national park,maple trees grow very large and live more than 80 years.Over an average lifetime,a tree produces more than 100,000 seeds,of which only 2-3 sprout and grow to maturity.This maple tree is

-The species shown in photo (a)has

In short,different selective pressures in closely related species will produce

In general,K-strategists have a

-This photo best illustrates

Many strategies have been used to control leafy spurge,including the deliberate introduction of different species of flea beetles that feed on leafy spurge.Each flea beetle female may lay about 200 eggs in her only year of life.In places where flea beetle introductions have quickly established large populations that have grown and stabilized,the population growth of these beetles most likely looked like

Competitive exclusion is not as common as many biologists expected,in large part because

In its broadest sense,fitness reflects the ability to respond to

Newly formed species typically have experienced different

The introduction of invasive North American ctenophores into the Black Sea and the Sea of Azov has

If organisms are unable to generate enough genetic diversity to survive in a changing environment,they

Parasites

A group of frogs in a rain forest represents a population if the frogs

A grasshopper population in a prairie is limited in large part by the number of birds in the region.Following a terrible storm that killed many of the birds,the grasshopper population exhibits exponential growth.This happens because the grasshoppers experienced

A keystone species

The relationship between the moose and wolf populations on Isle Royale reveals

A squirrel population in an oak forest in Indiana is limited by hawk predators,the amount of acorns produced annually,nesting sites in the trees,and cold winter temperatures. -The many factors listed above that can affect the squirrel population represent

A population that is at equilibrium

-The separate feeding locations of these five warbler species on different portions of the same tree illustrates