Speciation has definitely occurred when two groups of related organisms

A) cannot interbreed successfully.

B) have drastically different behaviors.

C) have drastically different appearances.

D) become permanently isolated from each other.

How did the nuclear arm race cause tension toward the Cold War?

Compare the energy production of the Three Gorges Dam to the Hoover Dam. Although China believed the Dam would provide the nation with 10% of its power needs, what is the current amount of power it actually is supplying?

Explain what cools off faster, land or water and why?

How a hot spot create an island chain

What clues will tell you about the colonial history of a region? check all that apply look at the language spoken see if the people have citizenry in another country check out the names of towns and cities find out what kind of transportation system

In your own words, describe how a primary wave moves.

Based on studies of planetary systems around other stars, which of the following statements are currently believed to be true about how common or rare it is for stars to have planets in orbit around them?

The less mass in a given volume of air, the a. more the air weighs. b. greater the air pressure. c. more dense the air. d. less dense the air.

Which is the most destructive kind of mass movement

What immediately happens to rainwater when it falls to earth? What eventually happens to it?