Biogenesis and Abiogenesis

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Commonly Misunderstood

Dictionary.com lists biogenesis and abiogenesis as commonly confused terms here. Its definitions as of 13 June 2023 are:

  • biogenesis
  1. "the production of living organisms from other living organisms"
  • abiogenesis
  1. "the theory that the earliest life forms on earth developed from nonliving matter"
  2. "the now discredited theory that living organisms can arise spontaneously from inanimate matter" (Spontaneous Generation)

Origin and derivation of the words

Biogenesis and Abiogenesis were neologisms introduced to the world by T. H. Huxley in 1870, in his Presidential Address to the Meeting of the British Association for the Advancement of Science at Liverpool. The full text of this address is reproduced in this wiki at Biogenesis and Abiogenesis - Huxley 1870 BAAS Presidential Address.

The two modes of Biogenesis

Thomas H. Huxley, who first proposed using the words "Abiogenesis" and "Biogenesis", credited Francesco Redi with describing two "modes" of Biogenesis, which Huxley termed homogenesis and xenogenesis.

Unlike Huxley, Redi hypothesised universal biogenesis: life begets life, all life comes from life.

 ● Homogenesis

"Like gives rise to like": offspring have the same life cycle as the parent.

 ● Xenogenesis

"Like gives rise to unlike, different": the series of states that offspring pass through is different from the parent's life cycle, which does not return in subsequent offspring

(As Huxley said, "Heterogenesis" would have been a better term, but was already used for something else.)

See here in Huxley's 1870 Address to the BAAS.

Significance with respect to Theism
In passing we may note that Redi's two modes of Biogenesis cover all that is required for a coherent concept of Theistic Evolution with "life first breathed into one or few forms". — Bruce

The quest for evidence of Abiogenesis

Abiogenesis, or emergence of life from non-life was also called spontaneous generation and archeobiosis (e.g. by H. Charlton Bastian) or archebiosis (e.g. by Darwin reviewing Bastian's Beginnings of Life in a letter to Wallace sent 28 August 1872.)

Darwin had written frankly about his own thoughts comparing creation preordained by God and "spontaneous generation" of life in an earlier letter to J. D. Hooker:

Your conclusion that all speculation about preordination is idle waste of time is the only wise one: but how difficult it is not to speculate. My theology is a simple muddle: I cannot look at the Universe as the result of blind chance, yet I can see no evidence of beneficent design, or indeed of design of any kind in the details.— As for each variation that has ever occurred having been preordained for a special end, I can no [more] believe in it, than that the spot on which each drop of rain falls has been specially ordained.—

Spontaneous generations seems almost as great a puzzle as preordination; I cannot persuade myself that such a multiplicity of organisms can have been produced, like crystals, in Bastian’s solutions of the same kind.— I am astonished that as yet I have met with no allusion to Wyman’s positive statement that if the solutions are boiled for 5 hours, no organisms appear; yet, if my memory serves me, the solutions when opened to air, immediately became stocked. Against all evidence I cannot avoid suspecting that organic particles (my gemmules from the separate cells of the lower creatures!) will keep alive & afterwards multiply under proper conditions. What an interesting problem it is.—

The Miller-Urey experiment, a famous 20th Century experiment by Stanley Miller and Harold Urey at the University of Chicago made abiogenesis more plausible, especially when the experiment was revisited nearly 70 years later; note, however that Darwin had anticipated such discoveries in his "simple muddle" of theology, with his focus on "preordination": the concept that the universe was created ready for abiogenesis to occur, not "as the result of blind chance". This, as always, left the question of a Creator as a search for evidence of "beneficence" — the same "problem of suffering" that many modern believers have — and an equally modern search for detailed evidence of design.

A paper published in August 2019 in the Proceedings of the [USA] National Academy of Sciences explains newly demonstrated mechanisms by which amino acids "could have" come together to form membranes, proteins and RNA. It was reported here with the overblown headline "Researchers Solve Puzzle of Origin of Life on Earth".

Relevance to Modern Discussion

Generally speaking, biogenesis as originally defined is irrelevant to the origin of life. Evolution of species is accounted for in its "xenogenesis" mode; ongoing creation of individuals is accounted for as "homogenesis". In every case, life comes from previously existing life.

Some modern authorities, however, use the term to mean simply "origin of life" and apply it to the concept of life arising from non-living material, thus synonymous with abiogenesis. This confusion masks the lack of evidence for abiogenesis — conveniently for militant atheists.

This, in turn, can be confusing for theistic evolutionists, who accept biogenesis in both of Redi and Huxley's "modes" but reject abiogenesis in favour of belief in the creation of the universe, and life within it, by the "one God and Father of all" (Ephesians 4:6).

Examples of confusion

  • As of 13 June 2023 the Wikipedia page for Biogenesis redirects to the "Pasteur and Tyndall" section of the Spontaneous generation page! There is a huge "Talk" page with a lot of argument, but no reference to original or subsequent definitions of Biogenesis which would exclude "spontaneous generation"!
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