PATHOLOGY

Detailed explanation-1: -These structures are important for carrying the weight of animals that walk on land. Finding this body part in animals that don’t walk on land is best explained how? Whales have evolved this structure because it might be useful in the future. Whales are able to interbreed with other animals that have hips.

Detailed explanation-2: -Comparing the embryos of different animals can show relationships that can’t be seen when comparing the fully formed animals. Why is this the case? Each embryo is unique; even embryos of animals of the same species can be different. When observing embryos, microscopes can be used to reveal more detail.

Detailed explanation-3: -Whales, lizards, humans, and birds all have the same basic limb layout. But how did such different animals wind up with the same sort of limb? The answer is that they inherited it from a common ancestor, just as cousins might inherit the same trait from their grandfather.

Detailed explanation-4: -This fossil snake and this living rat both have a structure in their skull called the quadrate bone. What best explains why both species have a quadrate bone? a The snake and rat are different species, so they must not be related. They inherited the quadrate bone structure from separate ancestor populations.

Detailed explanation-5: -The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time.