Editing Common descent (section)

==History==
{{See also|History of evolutionary thought}}

The idea that all living things (including things considered non-living by science) are related is a recurring theme in many indigenous worldviews across the world.<ref>{{Cite news|last=Staff|first=I. C. T.|title=We Are All Related: Indigenous Knowledge Reaffirmed by Digitized Tree of Life|url=https://indiancountrytoday.com/archive/we-are-all-related-indigenous-knowledge-reaffirmed-by-digitized-tree-of-life|access-date=2021-05-05|newspaper=Ict News|date=13 September 2018 |language=en}}</ref>  Later on, in the 1740s, the French [[mathematician]] [[Pierre Louis Maupertuis]] arrived at the idea that all organisms had a common ancestor, and had diverged through random variation and [[natural selection]].<ref>{{harvnb |Crombie |Hoskin |1970 |pp=[https://books.google.com/books?id=OOgzAAAAIAAJ&dq=Maupertuis+%22for+the+first+time%22&pg=PA62 62–63]}}</ref><ref>{{harvnb |Treasure |1985 |p=142}}</ref>

In 1790, the philosopher [[Immanuel Kant]] wrote in ''Kritik der Urteilskraft'' (''[[Critique of Judgment]]'') that the similarity{{efn|Now called [[Homology (biology)|homology]].}} of animal forms implies a common original type, and thus a common parent.<ref>{{harvnb |Kant |1987 |p=[https://books.google.com/books?id=y5wQD-ioaUUC&dq=Critique+of+Judgment+%22original+mother%22&pg=PA304 304]}}: "Despite all the variety among these forms, they seem to have been produced according to a common archetype, and this analogy among them reinforces our suspicion that they are actually akin, produced by a common original mother."</ref>

In 1794, Charles Darwin's grandfather, [[Erasmus Darwin]] asked:
<blockquote>[W]ould it be too bold to imagine, that in the great length of time, since the earth began to exist, perhaps millions of ages before the commencement of the history of mankind, would it be too bold to imagine, that all warm-blooded animals have arisen from one living filament, which {{Smallcaps |the great First Cause}} endued with animality, with the power of acquiring new parts attended with new propensities, directed by irritations, sensations, volitions, and associations; and thus possessing the faculty of continuing to improve by its own inherent activity, and of delivering down those improvements by generation to its posterity, world without end?<ref>{{harvnb |Darwin |1818 |p=397 [§&nbsp;39.4.8]}}</ref></blockquote>

[[Charles Darwin]]'s views about common descent, as expressed in ''[[On the Origin of Species]]'', were that it was probable that there was only one progenitor for all life forms:

<blockquote>Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed.<ref>{{harvnb |Darwin |1859 |p=484}}</ref></blockquote>

But he precedes that remark by, "Analogy would lead me one step further, namely, to the belief that all animals and plants have descended from some one prototype. But analogy may be a deceitful guide." And in the subsequent edition,<ref>Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2nd edition, second issue, page 466</ref> he asserts rather, <blockquote>"We do not know all the possible transitional gradations between the simplest and the most perfect organs; it cannot be pretended that we know all the varied means of Distribution during the long lapse of years, or that we know how imperfect the Geological Record is. Grave as these several difficulties are, in my judgment they do not overthrow the theory of descent from a few created forms with subsequent modification". </blockquote>

Common descent was widely accepted amongst the [[scientific community]] after Darwin's publication.<ref>Krogh, David. (2005). ''Biology: A Guide to the Natural World''. Pearson/Prentice Hall. p. 323. {{ISBN|978-0321946768}} "Descent with modification was accepted by most scientists not long after publication of Darwin's ''On the Origin of Species by Means of Natural Selection'' in 1859. Scientists accepted it because it explained so many facets of the living world."</ref> In 1907, [[Vernon Lyman Kellogg|Vernon Kellogg]] commented that "practically no naturalists of position and recognized attainment doubt the theory of descent."<ref>[[Vernon Lyman Kellogg|Kellogg, Vernon L]]. (1907). [https://archive.org/stream/darwinismtodaydi00kell#page/3/mode/2up ''Darwinism To-Day'']. Henry Holt and Company. p. 3</ref>

In 2008, biologist [[T. Ryan Gregory]] noted that:

<blockquote>No reliable observation has ever been found to contradict the general notion of common descent. It should come as no surprise, then, that the scientific community at large has accepted evolutionary descent as a historical reality since Darwin's time and considers it among the most reliably established and fundamentally important facts in all of science.<ref>{{Cite journal | doi=10.1007/s12052-007-0001-z|title = Evolution as Fact, Theory, and Path| journal=Evolution: Education and Outreach| volume=1| pages=46–52|year = 2008|last1 = Gregory|first1 = T. Ryan|doi-access=free}}</ref></blockquote>