Question

Which of the following mammals does not have a Pinna , nipple and uterus but has an abdominal testis .
A.Spiny anteater
B.Scaly anteater
C.Two eyed anteater
D.Banded anteater

Answer 1

Hint:Prototherians are primitive egg laying mammals. They have mammary glands but do not have nipples. They also do not have a pinna.In males the testes are situated inside the abdominal cavity .

Complete step by step answer: -Spiny anteater is the mammal that does not have a Pinna , nipple and uterus but has an abdominal testis .
-Spiny anteater is an egg laying mammal also known as prototherian.
-Scaly anteater is eutherian or placental mammal.
-Two eyed anteater is also known as giant anteater . Two eyed anteater is also an eutherian or placental mammal.
-Banded anteater is also known as marsupial anteater .

Sothe correct option is ( A )

Some additional information:
-Prototherians are mostly extinct . They were the primitive mammals. Prototheria means first breasts.
-Prototherians are the egg laying mammals. They also had abdominal testis.
-Prototherians are the subclass , which are the most ancestral forms in the class mammalia -There are only three extinct species grouped into two families in a single order the monotremata .
-It is not clear how they are linked with marsupial mammals ( Metatheria ) and placental mammals ( Eutheria ).
-Marsupial mammals give rise to partially developed young ones. And placental mammals give birth to well developed young ones.


Note: -Similarities between prototherians , Metatherians and eutherians all belong to Kingdom animalia , phylum Chordata and class Mammalia.
-They all are vertebrate animals.
-All prototherians are carnivorous.