Hypothetical life forms

most recent common ancestor of all current life on Earth

hypothesis about human evolution

thought experiment in philosophy

thumb|Structures found on meteorite fragment Allan Hills 84001

orange-yellow to black coating found on exposed rock surfaces in arid environments

thumb|upright=1.5| Structures found in the Allan Hills 84001|ALH84001 meteorite are similar to the structures found in nanobes

The humanzee (sometimes chuman, manpanzee or chumanzee) is a hypothetical hybrid of chimpanzee and human, thus a form of human–animal hybrid. Serious attempts to create such a hybrid were made by Soviet biologist Ilya Ivanovich Ivanov in the 1920s, and possibly by researchers in China in the 1960s; however, neither succeeded.

hypothetical form of life with mirror-reflected molecular building blocks (proteins, nucleic acids, etc.)

hypothetical microbial biosphere of Earth that would use radically different biochemical and molecular processes from that of currently known life

possible earliest ancestor of the LUCA ancestral cell

phenomenon and topic of discourse in evolutionary biology and biomechanics

hypothetical fossil that would falsify evolution

book by J.-H. Rosny aîné