Some scientists fear it could be underwater by 2050 or 2100.

What scientists fear most is a pandemic like one in 1918.

That's what scientists fear is happening to this year's migration.

Scientists fear that this could lead to a catastrophic warming of the earth in the 21st century.

Although no new urban cycle has yet been established, scientists fear that this could happen again at any point.

Scientists fear the release may have led to the ultimate extinction of at least five fish species.

Scientists fear major climatic changes as a result of the greenhouse effect.

Some scientists fear that will never happen if their habitat keeps shrinking.

The scientists who examined the skeleton, and their supporters, still fear that a political move could cut off future study.

Unfortunately, scientists fear that even this bird might have gone extinct.