Around 12,000 Years Ago, a Sudden Extinction Occurred on the Temperate

question 73

Multiple Choice

Around 12,000 years ago, a sudden extinction occurred on the temperate grasslands of North America, during which most of the diverse large mammal species died out. A corresponding extinction did not occur on the African savanna, also a temperate grassland, and today it still has diverse herds of large mammals. What possible, but controversial, explanation is thought by some people to explain the North American extinction?

• A) Declining habitat or food supply due to climate change
• B) Arrival of humans in North America
• C) Receding ice sheets, leading to a climate too warm to support megafauna
• D) Expanding ice sheets, leading to a climate too cold to support megafauna

---

Definitions:

Market Rate

The prevailing interest rate available in the marketplace on a particular debt instrument or the current price of goods, services, or securities.

Contract Rate

The agreed-upon interest rate specified in a contract, such as a loan or bond, which determines the periodic interest payments.

Premium

An amount paid in excess of the nominal or face value, often in relation to insurance policies, bonds, or shares.

Effective Interest Rate

The actual return on an investment, taking into account the effect of compounding interest as opposed to the nominal rate.