What Role Was Played by Fossils of the One-Toed Horse

question 72

Multiple Choice

What role was played by fossils of the one-toed horse when paleoanthropologists tried to assign firm dates to hominid-fossil-bearing layers at the eastern African site of Koobi Fora?

• A) The presence the fossils of one-toed horses confirmed that the horses appeared at Koobi Fora over half a million years earlier than they appeared in the Lower Omo Valley, a nearby site.
• B) The presence of the fossils at Koobi Fora, but not at Omo, convinced paleoanthropologists that previous biostratigraphy at the two sites was mistaken.
• C) The discrepancy between the one-toed horse fossil dates and the potassium-argon date caused paleoanthropologists to reexamine the potassium-argon date for Koobi Fora.
• D) The discrepancy between the one-toed horse fossil dates and the potassium-argon date caused paleaoanthropologists to realize that the hominid fossils at Koobi Fora were older than the Omo fossils.

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Definitions:

Poisson Distribution

A probability distribution that expresses the probability of a given number of events happening in a fixed interval of time or space, assuming these events happen with a known constant rate and independently of the time since the last event.

Probability Of Occurrence

The likelihood of an event happening, measured on a scale from 0 (impossibility) to 1 (certainty).

Span Of Time

The duration or extent between two points in time.

Poisson Random Variable

A type of random variable that represents the number of events occurring in a fixed interval of time or space, under the condition that these events happen with a known constant mean rate and independently of the time since the last event.