Which biogeographic realm has been separated from the other landmasses for more than 85 million years? (a) Ethiopian (b) Palearctic (c) Nearctic (d) Oriental (e) Australian

Which of the following is characteristic of most terrestrialbiomes?(A) a distribution predicted almost entirely by rock and soilpatterns(B) clear boundaries between adjacent biomes(C) vegetation demonstrating vertical layering(D) cold winter months

Because new species will eventually evolve to replace those that humans are driving to extinction, why is declining biological diversity such a threat?

The Permian extinction, which was the second most recent mass extinction, occurred about 251 million years ago. What is the leading hypothesis to explain the Permian extenction?     An asteroid about 6 km in diameter collided with Earth, which vaporized the caribbean ocean, set fire to north and south America, and expelled enough dust into the atmosphere to block the sun enough to result in a winter like environment all across the globe for several years     The Indian sub-continent collided with the Asian techtonic plate, giving rise to the Hymalayan mountains which altered the jet stream and caused the planet to enter an ice age     Massive amounts of volcanic activity released tons of CO2, enough to significantly increase the temperature of the planet     A new group of predators evolved that were significantly better at capturing prey, to the point that they drove many species (including other predators and eventually themselves) to extinction