Modern whales lack hind limbs, and have tail flukes and ears specialized for hearing underwater. Which of the following is the correct order for the evolution of these whale characteristics? A) Loss of hind limbs followed by tail flukes and underwater ears

B) Loss of hind limbs followed by underwater ears and tail flukes

C) Tail flukes followed by loss of hind limbs and underwater ears

D) Underwater ears followed by tail flukes and loss of hind limbs

The correct answer is B) Loss of hind limbs followed by underwater ears and tail flukes.

Explanation:

Scientists estimate that the evolution of the Whale in the form which it now takes started approximately 50 Million years ago.

The most likely land animal to have taken the step to move back into the ocean is said to be the Bear. Even today, bears are known to be excellent swimmers and can swim and hunt in water and underneath it.

Other animals that have been suspected to have made this move, hence being the animal that evolved is the Hippopotamus.

Their transition is estimated to have taken only 10 million years. According to some scientists, this is the shortest time ever taken for any evolutionary transition to occur.

Why would a successful land animal transit into the sea? The answer is attributed to opportunity. Opportunity to feed even better and hence survive.

This is why the teeth is reported to have evolved first.

The next most immediate need for the transiting mammal was the ability to maneuver in its new environment - the waters. Hence the next evolutionary step was modified or specialized ears which helped them to hear properly and navigate underwater.

After this was the changes that occurred to their limbs.

nScientists refer to the Ambulocetus as the species that connects the dots on this one. It is said to have had specialized teeth for hunting, limbs that were already adapted for underwater swimming and hunting but whose tail was still intact as that of a land animal.

Cheers

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