But scientists think it was either a comet or rock from space.

VOA: special.2009.08.25

Today,most scientists think the islands were always where they are now.

VOA: special.2009.12.16

Scientists think most Galapagos plants and animals floated to the islands.

VOA: special.2009.12.16

But scientists think the dinosaurs developed feathers first, and then wings.

VOA: special.2010.06.04

Now,a team of U.S.scientists think they're on track to developing a "universal" vaccine that will protect people against all kinds of influenza.

VOA: standard.2010.07.21

Scientists think that such unseasonal temperatures are the result of both global warming and natural climate variability.

VOA: standard.2009.09.03

Climate scientists think accumulated gases are contributing to global warming and weather changes.

VOA: standard.2009.12.16

Some climate scientists think the Australian continent is particularly susceptible to a shifting climate and predict a greater incidence of droughts, floods and storms as the Earth warms.

VOA: standard.2009.11.09

Scientists used to think that the islands were connected to the South American mainland and floated out to sea slowly.

VOA: special.2009.12.16

You would think that all the scientists who took part in a research study would be listed as authors.

VOA: special.2009.10.08

Not only that, but most of those genes are of a kind that scientists used to think of as molecular junk.

VOA: standard.2010.04.05

A long-standing drought, along with recent devastating bushfires and widespread floods have given some scientists more reason to think that the vast continent is likely to be one of the countries hardest hit by a shifting climate.

VOA: standard.2009.05.03