A related hypothesis involves the natural chemiluminescence of phosphine.

Another hypothesis involves climate change.

The tidal or gaseous hypothesis of the earth involves an original sun that had a close encounter with a passing star.

Two linguistic hypotheses for the etymology of xian involve the Arabic language and Sino-Tibetan languages.

One recent computational hypothesis involves cascades of plasticity that allow synapses to function at multiple time scales.

Another hypothesis involves ocean venting of hydrogen sulfide gas.

Current hypotheses about the causes of this behavior involve diet, social interaction, and altitude.

It is unclear how chitosan does this, but the currently favored hypotheses involve the increase of intestinal viscosity or bile acid-binding capacity.

Another hypothesis could involve the radiator.

A leading hypothesis involves calcium, crucial to maintaining cell integrity, among other functions.