Law of biogenesis

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Law of biogenesis

-->recapitulation theory

The theory formulated by E.H. Haeckel that individuals in their embryonic development pass through stages similar in general structural plan to the stages their species passed through in its evolution; more technically phrased, the theory that ontogeny is an abbreviated recapitulation of phylogeny. The theory has been discredited in the light of the modern science of genetics. even at the time, there was much reason to doubt its validity. Especially as Haeckel himself was ordered to appear before a university court in Jena were he was accused of faking the evidence for recapitulation. He finally admitted that his evidence had been 'doctored'.Synonym: biogenetic law, haeckels theory, embryonic recapitulation.

Law of biogenesis The law which states, life arises only from existing life. Formulated after many years of extensive observation and experimentation. The early greeks believed that living things could originate from nonliving matter (abiogenesis) and that the goddess Gea could make life arise spontaneously from stones. aristotle disagreed, but still believed that creatures could arise from dissimilar organisms or from soil (an early form of evolution theory). variations of this concept of spontaneous generation still existed as late as the 17th century, but towards the end of the 17th century a series of observations, experiments, and arguments began that eventually discredited such ideas. This advance in scientific understanding was met with much opposition, with personal beliefs and individual predjudices often obscuring the facts. Francesco Redi, an Italian physician, proved as early as 1668 that higher forms of life could not originate spontaneously, but proponents of abiogenesis claimed that this did not apply to microbes and continued to hold that these could arise spontaneously. attempts to disprove the spontaneous generation of life from non-life continued in the early 1800s with observations and experiments by Franz Schulze and Theodor Schwann.

In 1864 louis pasteur finally announced the results of his scientific experiments. In a series of neat experiments, pasteur proved conclusively that only pre-existing microbes could give rise to other microbes (biogenesis). thus dr. louis pasteur finally overcame the longstanding belief in spontaneous generation of life. even so (regardless of the evidence) the belief that life could spontaneously arise from non-life (abiogenesis) was still stubbornly held on to by some, including thomas Huxley ('Darwin's Bulldog').

however, the law of biogenesis is now well established and it is generally accepted by scientists that abiogenesis has no scientific validity. The medical profession and food industry rely totally on the validity of the law of biogenesis for hygiene, sterilisation and food preservation.