Question

acidna is
1- connecting link
2- vestigial organ
3- extinct link
4- none of these

Answer 1

I think it is not Acidna it is Echidna.

Echidna is a connecting link between mammals and reptiles.

• Echidns is a spiny anteater. These are the egg-laying mammals.

• Echidna's belongs to the family Tachyglossidae.

• The echidna is a subspecies of monotremes. These are having a connecting link between reptiles and mammals.

• The echidna has both mammal and reptile characteristics, they lay eggs like reptiles and they have memory glands like mammals.

Answer 2

Acidna is extinct link.

Explanation:  

• Echidna is one of the spiny anteater mammal which is found in Africa and Australia.

• chidna can be considered as an extinct link between mammals and other types of chordates.  

• Vestigial organ is one of the organ which is not used by the animal but it is a type of organ which is still found in the animal.  

• However echidna is not fully and extinct organ but it is an example of an endangered species.

Learn more about Acidna

Explain how pinna is a vestigial organ.

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Examples of vestigial organs in plant Atleast 5​

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