Refer to the figure. The diversification of multicellular lineages associated with the Cambrian explosion lasted about _______ percent of the span of time during which life existed before the Cambrian explosion.

Question

Refer to the figure.  The diversification of multicellular lineages associated with the Cambrian explosion lasted about _______ percent of the span of time during which life existed before the Cambrian explosion.

Quizplus · Accepted Answer

According to the figure, the Cambrian explosion occurred about 542 million years ago, and the total span of time during which life existed before the Cambrian explosion was about 3 billion years. Therefore, the diversification of multicellular lineages associated with the Cambrian explosion lasted about 20 million years (542-522 million years ago) out of a total of 3 billion years, which is approximately 2% (20/1000) of the total time span. Thus, the best choice is C).

Refer to the Figure