MCQ
Q.
From the point of view of evolution of living organisms, which one of the following is the correct sequence of evolution ?
Correct Answer: B
The correct answer is Shark — Tortoise — Otter.
Key Points
- Shark - Scientists believe that sharks came into existence around 400 million years ago. It is believed that they descended from a small leaf-shaped fish that had no eyes, bones on fins.
- These fish then evolved into two main groups of fish that are found today.
- Bony fish and cartilaginous fish which include shark and Chimaira.
- Sharks are on the top of the marine food chain and are the only huge marine reptiles that exist today.
- Tortoise is believed to have existed for 250 million years.
- They belong to the reptile species of the family Testudinidae.
- Tortoise has a hard shell to protect from the outside environment. They are believed to have evolved from very large body sizes of around 100 kgs. They are among the longest-living land animals in the world.
- Otters are believed to have existed on earth for the past 23 million years.
- They have evolved significantly and have gone through many adaptations to survive till this time.
Additional Information
- They have the ability to move both on water and land except sea otters. The rest of the otters have webbed feet which help them to move in the water.
- They have five toes which help them to move on land as well. It is believed that they were once land animals only but they ended up going in the water to be safe from predators.
- It is also believed that the food sources were available in limited quantities on land so they started hunting in water to survive.
