Reptiles

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Soon a group of vertebrates called reptiles solved the problem of how to reproduce without water, and they did it in exactly the same way, as the insects. Fertilization occurred before the eggs were laid, by the male injecting sperm into the female's body.

She used it to fertilize her eggs which she then covered with a tough water-proof skin and laid on land. No surface water was needed for reproduction.

Reptiles had scaly skin. They probably could not keep themselves warm when the weather was cold or at night-time, and may have become slow and sleepy at these times, although there is some debate about this.