Question

Which of the following sets of features of Echidna/Platypus makes them form a link between reptiles and mammals?

• A. Produce milk for their offspring even though they lays eggs
• B. Eggs with yolk and hair on body
• C. Egg shell and presence of diaphragm
  
• D. All of the above

Answer 1

Answer: (D)

All of the above

Platypus and Echidna are warm-blooded animals. They belong to Mammalia because they have hair on their body and produce milk from mammary glands to feed their young ones. However, they lay eggs without giving birth to young ones. Laying eggs is characteristics of class Reptilia. Hence they form a link between reptiles and mammals.

So, the correct answer is 'All of the above'.