English

Todd

18 April, 18:06

Some scientists believe that the slow repositioning of Earth's

landmasses lead to the extinction of dinosaurs. Convection

currents within the Earth's mantle caused landmasses to drift,

collide, and eventually heave upward. Ocean currents were

redirected and sea levels throughout the planet dropped. For

example, the interior seaway, which once divided North America,

drained away as the Colorado Plateau rose thousands of feet into

the air. Without shallow seas like this one, climates became

cooler and drier. Such climatic change resulted in new

ecosystems that could not provide enough biomass to support

dinosaur life.

Which scenario leading to the extinction of the dinosaurs is NOT

discussed in the two passages which discuss possible theories?

A) a flood

B)

an asteroid

unstable earth

D)

erupting volcanoes