Question

Extinct vs. Modern Skulls



Scientists study fossils of animals that lived in the past. They look at the anatomical structures (features of the fossil) to better understand these ancient organisms. By looking at the anatomical structures, scientists can get a better understanding of the animal's diet, environment, and interactions with other animals. Scientists compare their findings to animals that are alive today. Similarities between ancient fossils and modern-day animals mean they may be related. Animals that are related also have differences, but these differences help explain how animals have changed over time.



The picture shows the skull of an extinct animal that lived about 10,000 years ago.



Scientists believe this animal was an herbivore. An herbivore is an animal that only eats plants. There are some key features that scientists see in this fossil:

It has front teeth on the lower jaw, but only a chewing pad in the front on the top jaw. This indicates that this animal grazed on plants.
It has eye sockets off to the sides of the skull. This allows the animal to see predators approaching.
It has horns. This allows the animal to defend itself against predators.
The drawings show four modern-day animals.

Drawing A shows the top and side view of a skull with horns, blunt teeth on the upper and lower jaws, and eye sockets on the sides of the skull. Drawing B shows the top and side view of a skull with no horns, sharp teeth on the upper and lower jaws, and eye sockets that face forward. Drawing C shows the top and side view of a skull with no horns, sharp teeth on the upper and lower jaws, and eye sockets that face forward. Drawing D shows the top and side view of a skull with no horns, blunt teeth on the upper and lower jaws, and eye sockets on the sides of the skull.



Why do scientists compare ancient fossils with modern organisms?


to conclude evolutionary relationships


to describe past environmental conditions


to predict future animal characteristics


to explain dietary needs of modern animals

Answer 1

to conclude evolutionary relationships

Scientists compare fossil anatomy with modern organisms because similarities can indicate relatedness and differences show how species have changed over time.