Question

Vestigial pelvic girdle and bone remnants of hind limbs are the characteristics of
A. Whale
B. Dolphin
C. Shark
D. Seal

Answer 1

Hint: This animal is a fully aquatic mammal.
They have evolved from land- living mammals.
They have blowholes on their heads for exchange of air.

Complete answer:
Vestigial pelvic girdle means the pelvic bone is present but they do not perform any function that’s why it is known as vestigial pelvic girdle.
Whales are large mammals.
It is a tetrapod with flippers.
The flippers are the forelimbs of the whale.
It has no hind limbs in the course of evolution.
When the bone structure of the whale is noticed it is seen that girdles allow the bones of the limbs to attach to the whole axial skeleton.
In the case of whales the hindlimbs are not required due to their permanent adaptation to aquatic life.
So these girdles are not of use in the whale.
These bones are a part of a whale but they are rudimentary and ill conditioned.
They are of no function.
Hence these are called vestigial.
Dolphins have two stomachs.
They dive upto 1000 feet.
They live upto 50 years.
They never chew their food.
Sharks have a covering of dermal denticles that protects their skin from damage and parasites in addition to improving their fluid dynamics.
Seals are an aquatic mammal that lives chiefly in cold seas and whose body shape, round at the middle and tapered at the ends, is adapted to swift and graceful swimming.
They have numerous sets of replaceable teeth.

So, the correct option is option A. Whale.

Note: Whales have a torpedo shape of the body.
Their neck is not flexible.
They have small eye orbits.
They are warm blooded animals.
Whales are fast swimmers due to flippers.