In 1991, scientist James Estes and his team observed a new trend of orcas preying on sea otters. Orcas normally prey on great whales, but those populations had been dramatically reduced by industrial whaling. Estes hypothesized that the decrease in the great whale population had caused orcas to turn to smaller prey -- sea otters. If this hypothesis is correct, predict what might happen to sea otter numbers if great whale population numbers increase.

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

What is the farthest destination to date for a human spaceflight mission?

Speed is the ratio of the distance of an object moves to