You are given a sentence and your task is to generate another sentence that supports the given input.

Placental mammals give birth to a relatively large and mature fetus.
Placental mammals give birth to relatively large fetuses.

Viral vectors are a tool commonly used by molecular biologists to deliver genetic material into cells.
A viral vector is the name for a tool commonly used by molecular biologists to place genetic material into cells.

Birds evolved from reptiles some 60 million years ago, and in that time the humble scales of the lizard-like ancestor of the bird (archaeopteryx) have been transformed into the staggering diversity and beauty that we now know as the plumage of modern birds.

Birds evolved from reptile ancestors.

