书城外语课外英语-动物亮丽风景线(双语版)
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第81章 生活周期

Females crocodilians lay from 20to 90eggs.They lay their eggs in nests made of sand,mud,or rotting plant parts.Baby crocodilians hatch from the eggs.

Most female crocodilians watch over their young.Alligator mothers may help the babies break out of the egg.They sometimes carry the newborn alligators in their mouths.They put the babies into the water.Some mothers stay near their young for at least a year.If the young alligator gets in trouble,its mother is there to help.

No one is really sure how long alligators and crocodiles live.Scientists estimate that smaller species can live from 30to 50years,while larger crocodilian species can live to be 70or even 80years old.

Threats to Crocodilians