Biogenesis

Biogenesis is the process of lifeforms producing other lifeforms, e.g. a spider lays eggs, which form into spiders.

The term is also used for the assertion that life can only be passed on by living things, in contrast to abiogenesis, which holds that life can arise from non-life under suitable circumstances.

Until the 19th century, it was commonly believed that life arose from non-life under certain circumstances, a process known as spontaneous generation. This belief was due to the common observation that maggots or mold appeared to arise spontaneously when organic matter was left exposed. However, with the advent of modern biology, it was discovered that life could only arise from life, a principle summarized in the phrase, Omne vivum ex vivo, Latin for "all life [is] from life."

Law of biogenesis

The concept that life can only come from life, summarized in Pasteur's famous aphorism that "La génération spontanée est une chimère," rests on an empirical basis. "Life has never been observed arising from non-life under any circumstances," so the argument goes, "and it is therefore unreasonable to believe it ever did."

In biology, an entity has traditionally been considered to be alive if it exhibits all the following phenomena at least once during its existence:

1. Growth
2. Metabolism, consuming, transforming and storing energy/mass; growing by absorbing and reorganizing mass; excreting waste
3. Motion, either moving itself, or having internal motion
4. Reproduction, the ability to create entities that are similar to itself
5. Response to stimuli - the ability to measure properties of its surrounding environment, and act upon certain conditions.

A number of efforts have been made to bring life from non-life, but none has yet succeeded. J. B. Burke attempted to produce small living cells from inorganic matter by means of radium were unsuccessful; the radiobes produced were merely bursting gas bubbles of microscopic size. Pflüger produced cyanic acid, which he compared to half-living molecules, but it was merely a dead chemical compound. The Miller-Urey experiment produced some of the organic components of life, but failed to produce a living, reproducing organism.

Biogenesis is the basis of Creation biology, which holds that since life cannot arise spontaneously from non-life, life must, of necessity, have been created by God.

See also

• Origin of life
• Omne vivum ex ovo