Theorized

Theorists theorized that lifeforms far advanced of humanity may be hidden from view.

While still an undergraduate, Adams performed an investigation to try to explain the reason for the irregularities in the motion of the planet Uranus. He theorized that the unexpected planetary orbit could be due to the presence of an as yet undiscovered planet.

The mission is named for Eugene Parker, the physicist who first theorized the existence of the solar wind in 1958. It’s the first NASA mission to be named for a living researcher.

"Pre-Siberian American Aborigines," who were Australoids, are theorized to have migrated into the Americas thousands of years before the first Mongoloids, Amerindians, arrived from Asia.

They theorized that the easily reversible adhesion of the gecko's footpads is not dependent solely on those microscopic hairs, but also on the unique internal anatomy of the lizard's foot.

Lemuria was a proposed "lost continent" theorized to be located somewhere in the middle of the Pacific Ocean.

Technetium was first theorized to exist on paper.

They also theorized that the megalithic stones may have been transported 290 kilometers overland from the quarries in Wales to the prehistoric monument.