Biogenesis, << `by` oh JEHN uh sihs, >> is a term in biology that is derived from two Greek words meaning life and birth. According to the theory of biogenesis, living things descend only from living things. They cannot develop spontaneously from nonliving materials. Until the mid-1800’s, scientists believed that certain forms of life arose spontaneously from nonliving substances. By actual experimentation, the great French scientist Louis Pasteur disproved this false theory of spontaneous generation, also known as abiogenesis. Today, however, scientists are examining the theory that the first forms of life gradually came into being from lifeless matter millions of years ago.
The term biogenesis has also been used in reference to the biogenetic (or recapitulation) theory. This theory, which was popular during the late 1800’s, stated that “ontogeny recapitulates phylogeny.” This statement means that during its ontogeny–that is, during its development in the embryonic stage–each organism recapitulates (repeats) various stages in its species’ phylogeny (evolutionary history). Scientists disproved this theory in the early 1900’s.
