Traditionally, Whales and Hippopotamuses Have Been Classified in Different Orders

question 25

Multiple Choice

Traditionally, whales and hippopotamuses have been classified in different orders, the Cetacea and the Artiodactyla, respectively. Recent molecular evidence, however, indicates that the whales' closest living relatives are the hippos. This has caused some zoologists to lump the two orders together into a single clade, the Cetartiodactyla. There is no consensus on whether the Cetartiodactyla should be accorded order status or superorder status. This is because it remains unclear whether the whale lineage diverged from the lineage leading to the hippos before or after the other members of the order Artiodactyla (pigs, camels, etc.) diverged (see Figure 20.2) .
Figure 20.2 contrasts the "Within the artiodactyls" origin of the whale lineage with the "Without the artiodactyls" origin of the whale lineage.
-What can be properly inferred from Figure 20.2?

• A) In the "Without" tree, pigs are more distantly related to hippos than is depicted in the "Within" tree.
• B) In the "Without" tree, pigs are more closely related to hippos than are whales.
• C) In the "Within" tree, pigs are more closely related to whales than they are to hippos.
• D) The "Without" tree is more consistent with molecular evidence than is the "Within" tree.
• E) In the "Within" tree, all artiodactyls, including hippos, are more closely related to each other than any are to the whales.

---

Definitions:

Young Adulthood

The time period from about 18 to 30 years that is often an extended period of transition involving exploration of potential adult identities.

Intimacy

A quality of interpersonal relating through which partners share personal thoughts, feelings, and other important aspects of themselves with each other. True intimacy is marked by openness, affection, and trust.

Generativity

A motive or need that can be filled through one’s vocation or avocations, through child rearing, or through community service. It includes productivity and creativity. Generativity also describes people who are contributing members of society.

Earned Secure

An attachment style characterizing adults who in Adult Attachment Interview transcripts reveal experiences of early adversity, describe their painful backgrounds truthfully, acknowledge the stressors their own parents faced, and come to terms with their early experiences. Their children are usually securely attached.