| the seas and atmosphere on earth before the existence of life, primarily containing a mixture of water, hydrogen, methane, ammonia, and carbon dioxide |
| variation in traits such as body weight or height in which a series of types are distributed on a continuum, not grouped into discrete categories |
allotype al·lo·type (āl'ə-tīp')
n.
Any of the genetically determined antigenic differences within a given class of immunoglobulin that occur among members of the same species.