Mammals were not contemporaries of the dinosaurs. select the best answer from the choices provided t f

False

Explanation:

There were several mammals during the age of dinosaurs that were contemporaries of  dinosaurs.  

For example –  

a)Megazostrodon – Megazostrodon were the first mammal that emerged some 220 million years ago. They resembled to rats of present time, had hairy body , feed upon insects and reptiles, produce milk for their young ones and also has three kinds of teeth just like mammals.  

b)Didelphodon – These mammals resembled the  size of present day cat and possesses characteristics of both dinosaurs and mammals ( milk production, three kind of teeth, body hair).

they are known to reach a speed of 21 miles per hour

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