Please use the following information to answer the questions below.
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 20.5).
Figure 20.5
-What can be properly inferred from Figure 20.5?
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.

Question

Please use the following information to answer the questions below.
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 20.5).
  Figure 20.5
-What can be properly inferred from Figure 20.5?
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.

Quizplus · Accepted Answer

In the "without" tree, the branch length between pigs and hippopotamuses is shorter than in the "within" tree, indicating a closer relationship. However, in both trees, the branch length between whales and hippos is shorter than the branch length between pigs and hippos, indicating a closer relationship between whales and hippos than between pigs and hippos. This supports the molecular evidence that whales and hippos are more closely related than previously thought, and that they may be grouped together in a single clade.

Please Use the Following Information to Answer the Questions Below