Biology : Taxonomy Part-I

21. Which one is a mammal? [R.A.S./R.T.S. (Pre) 2010]

(a) Shark
(b) Squid
(c) Octopus
(d) Whale

Correct Answer: (d) Whale

Solution:Whales are the largest mammals ever known to have lived on earth. Whales range in size from the blue whale, the largest animal known to have ever existed at 33 m, and more than 180 tons to pygmy species such as the pygmy sperm whale at 3.5 m (11 ft).

22. Which of the following species is the largest of the ‘toothed-whales’? [U.P.P.C.S. (Pre) (Re. Exam) 2015]

(a) Finback whale
(b) Blue whale
(c) Sperm whale
(d) Humpback whale

Correct Answer: (c) Sperm whale

Solution:The sperm whale (Physeter macrocephalus) is the largest of the toothed whales with males growing up to 20 metres in length. The mass of sperm whales ranges between 35 to 45 tons; females only weigh about 1/3 of the males

23. Which among the following one lays eggs and does not produce young ones directly? [I.A.S. (Pre) 2008]

(a) Echidna
(b) Kangaroo
(c) Porcupine
(d) Whale

Correct Answer: (a) Echidna

Solution:Echidnas, sometimes known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species, together with the Platypus are the only surviving members of that order and are the only living mammals that lay eggs. Their diet consists of ants and termites but they are not closely related with the true anteaters of America. They live in Australia and New Guinea.

24. Which of the following mammals lays eggs? [U.P. P.C.S. (Pre) 2022]

(a) Loris
(b) Kangaroo
(c) Hedgehog
(d) Echidna

Correct Answer: (d) Echidna

Solution:Echidnas, sometimes known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species, together with the Platypus are the only surviving members of that order and are the only living mammals that lay eggs. Their diet consists of ants and termites but they are not closely related with the true anteaters of America. They live in Australia and New Guinea.

25. Mammal capable in flying is— [M.P.P.C.S. (Pre) 2010]

(a) Jaguar
(b) Ostrich
(c) Pelican
(d) Bat

Correct Answer: (d) Bat

Solution:Bats are the mammals of the order Chiroptera whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. Bat does not belong to the group aves (birds).

Key points about bats:

Wings: Bats have wings that are modified versions of their hands.
Echolocation: Bats use echolocation to navigate and hunt, which helps them fly in the dark.
Sustained flight: Bats can fly for long distances and maintain altitude, unlike gliding mammals.

26. Amongst the following flying organisms, which one does not belong to the group, Aves? [U.P.P.C.S. (Mains) 2011]

(a) Bat
(b) Crow
(c) Eagle
(d) Parrot

Correct Answer: (a) Bat

Solution:Bats are the mammals of the order Chiroptera whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. Bat does not belong to the group aves (birds).

27. Consider the following animals [I.A.S. (Pre) 2013]

Sea Cow/Dugong/Manatee: These are large, herbivorous marine mammals that primarily eat seagrass. They are unique among marine mammals for their exclusively herbivorous diet.
Seahorse: Seahorses are fish, belonging to the class Pisces. They are not mammals.
Sea Lion: Sea lions are mammals, belonging to the order Pinnipedia, which includes seals and walruses. They are not herbivorous.

Hence option (b) is correct.

(a) Only 1
(b) 1 and 3
(c) 2 and 3
(d) All of these

Correct Answer: (b) 1 and 3

Solution:Sea cow is a huge herbivorous sea mammal. Seahorse is a small species of Pisces. Sea lion is also a mammal. Hence option (b) is correct.

28. Dolphins are classified in – [40th B.P.S.C. (Pre) 1995]

(a) Fish
(b) Amphibians
(c) Reptile
(d) Mammals

Correct Answer: (d) Mammals

Solution:Dolphins are highly intelligent aquatic mammals and are part of the family of toothed whales. They are found worldwide, mostly in shallow seas off the continental shelves and are carnivores, mostly eating fish and squid. India has declared Ganga Dolphin as the national aquatic animal.

29. From the following option, seal is the species of— [Uttarakhand U.D.A./L.D.A. (Pre) 2003]

(a) fish
(b) bird
(c) reptiles
(d) mammal

Correct Answer: (d) mammal

Solution:Seals are semi-aquatic mammals, they are in a group called pinnipeds meaning fin-footed. All seals are carnivores. Their diet consists of mostly fish, crustaceans, and shellfish.

30. Amphibians are — [38th B.P.S.C. (Pre) 1992]

(a) Very fastly moving boats
(b) Animals living in water only
(c) Animals living on land only
(d) Animals living equally in water and on land both

Correct Answer: (d) Animals living equally in water and on land both

Solution:The word 'amphibian' is derived from the ancient Greek term amphibios, which means ‘both kinds of life’. The term was initially used as a general adjective for animals that could live on land or in water. They are ectotherms or cold-blooded animals, meaning they are unable to regulate their own body temperature.