Common descent
A group of organisms is said to have common descent if they have a common ancestor. In biology, the theory of universal common descent proposes that all organisms on Earth are descended from a common ancestor or ancestral gene pool.¹A theory of universal common descent based on evolutionary principles was proposed by Charles Darwin in his book The Origin of Species (1859), and later in The Descent of Man (1871). This theory is now generally accepted by biologists, and the last universal common ancestor (LUCA), that is, the most recent common ancestor of all organisms, is believed to have appeared about 3.5 billion years ago.
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2 Evidence for common descent 3 Relevance to Creationism 4 Footnote |
The first suggestion that all organisms may have had a common ancestor
seems to have been made in 1745 by the French mathematician and scientist
Pierre-Louis Moreau de Maupertuis (1698-1759) in his work Vénus physique.
In 1790, Immanuel Kant (Königsberg (Kaliningrad) 1724 - 1804), in his Kritik der Urtheilskraft, states that the analogy of animal forms implies a common original type and thus a common parent.
In 1795, Charles Darwin's grandfather, Erasmus Darwin, hypothesized that all warm-blooded animals were descended from a single "living filament":
The universality of the genetic code is generally regarded by biologists as definitive evidence in favor of the theory of universal common descent for all bacteria, archaea, and prokaryotes (see Three domain system). A tree showing the paths of descent from a common ancestor is depicted in the article on Phylogenetic trees.
Exactly how viruses fit into the picture is still uncertain, especially since some are based on RNA rather than DNA. However, viruses are not usually regarded as organisms.
Some Creationists do not accept the theory of universal common descent, arguing that humanity was created by God in a distinct act of creation, whereas the rest of life evolved.History
Evidence for common descent
Relevance to Creationism
