Question

individual elephants and arctic herbivores such as caribou tend to have fixed geographic ranges throughout their lifetimes, which had prompted some researchers to speculate that the arctic woolly mammoth, an extinct elephantid, might have exhibited similar behavior. mammoth tusks grew in sequential layers, incorporating ingested minerals and organics, and so each ivory stratum reflects the ratio of strontium isotopes (87sr/86sr) in the local environment; thus, the sequence of strata shows where the animal roamed during life. recent analysis of the strontium ratios in the strata of one arctic woolly mammoth tusk in relation to the geographic distribution of strontium ratios in the environment shows the animals range began to expand as it reached sexual maturity, only to contract again in its final 1.5 years. which choice best describes the function of the underlined statement in the text as a whole? a) it describes a similarity in the behavior of certain animals in order to show why a method described later in the text did not reveal whether another animal also showed that behavior. b) it discusses a characteristic shared by certain animals in order to explain why researchers raised a possibility that turned out not to be supported by data described later in the text. c) it illustrates a pattern of behavior among certain animals in order to present a theory about exceptions to that pattern that is weakened by a finding described later in the text. d) it introduces a trait shared by certain animals in order to contextualize a hypothesis about the origin of that trait that is advanced later in the text.

Explanation:

The text discusses the function of the underlined statement. The statement shows the geographic distribution of strontium ratios in the environment, which helps in understanding the movement and behavior of animals (like mammoths) as their tusks incorporate these ratios. This is a method (looking at strontium ratios in tusks related to the environment's strontium ratios) described later in the text to study animal behavior.

Answer:

A. It describes a similarity in the behavior of certain animals in order to show why a method described later in the text did not reveal whether another animal also showed that behavior.