Question

Q12. Why certain organisms that once lived on earth have completely disappeared.

Answer 1

Answer:

because by the evolution process the organisms that once lived is completely disappeared

Answer 2

The animals that once lived on earth have completely disappeared bcz the environment of earth is being changed .Due to it temeprature rises in some region ,habitats of certain animals have also been destroyed by formation of mountains,etc. Humans have also been destroying the habitats of animals and killing the animals too.The species which can not tackle these situations get died and their species also endanger.

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