Question

In 2006, scientists discovered fossilized skeletons of an animal with several interesting features. Fossil evidence indicated that the animal not only had scales, fins, and gills, but also had lungs, a full set of ribs, and limb bones arranged to support the animal’s weight. The illustration below shows what the animal, called Tiktaalik, probably looked like based on the fossil evidence.Which of the following statements best explains why the Tiktaalik fossils are an important piece of evidence for evolution?

A. They include skeletons of both males and females.
B. They are complete skeletons of a carnivorous animal.
C. They allow scientists to estimate the animal’s lifespan.
D. They show a transitional form between fish and land-dwelling vertebrates.

Answer 1

The preferable statement will be - D.

D. They show a transitional form between fish and land-dwelling vertebrates.

Explanation:

From the given information we know that the fossil of that type of animal has scales, fins, gills, lungs, a full set of ribs, and limb bones.

This indicates some things such as,

• There is a high chance that the animal was capable of living in both land surface and water.

• Scales, fins, and gills indicate that they were like fish or water vertebrates.

• But lungs, a full set of ribs, and limb indicates that they are showing a transitional form between water and land-vertebrates.