11.   Scientists long assumed that humans evolved melanin, the main determinant of skin color, to absorb or disperse ultraviolet light.

12.   Scientists assume that great numbers of neutrinos constantly stream through human beings and everything else on Earth, causing neither sensation nor discernible injury.

13.   Scientists generally assume that lightning provided the energy for converting chemicals into molecules that led to life on Earth some four billion years ago.

14.   Scientists have assumed that the cosmic particles must originate nearby the Solar system, because they would lose their high energy on significantly longer journeys.

15.   Scientists have long assumed, though, that we must see shape in the same way at all sizes.

16.   Space probes showed that the polar caps of Mars contain water, not simply carbon dioxide, as many scientists had assumed.

17.   The finding was such a challenge to conventional theories that most scientists assumed they would quickly discredit the theory.

18.   These deer appear in specific geographic pockets, and scientists assume that this is because of inbreeding in areas of sparse population.

19.   Until recently, many scientists assumed that nest temperatures determined the sex of dinosaurs, as it still does for many surviving reptiles.

20.   Until now, Fauci said, scientists had assumed virus particles remaining in cells after treatment with the drug combinations were dead and incapable of returning to activity.