Clay Hypothesis
A model for the origin of life based on clay was forwarded by A. Graham Cairns-Smith of the University of Glasgow in 1985 and explored as a plausible illustration by several scientists. The Clay hypothesis postulates that complex organic molecules arose gradually on a pre-existing, non-organic replication platform of silicate crystals in solution.
Cairns-Smith is a trenchant critic of other models of chemical evolution. However, he admits that like many models of the origin of life, his own also has its shortcomings.
In 2007, Kahr and colleagues reported their experiments that tested the idea that crystals can act as a source of transferable information, using crystals of potassium hydrogen phthalate. "Mother" crystals with imperfections were cleaved and used as seeds to grow "daughter" crystals from solution. They then examined the distribution of imperfections in the new crystals and found that the imperfections in the mother crystals were reproduced in the daughters, but the daughter crystals also had many additional imperfections. For gene-like behavior to be observed, the quantity of inheritance of these imperfections should have exceeded that of the mutations in the successive generations, but it did not. Thus Kahr concluded that the crystals, "were not faithful enough to store and transfer information from one generation to the next".
Read more about this topic: Abiogenesis, Other Models
Famous quotes containing the words clay and/or hypothesis:
“Archaeologists have uncovered six-thousand-year-old clay tablets from southern Babylonia that describe in great detail how the adults of that community found the younger generation to be insolent and disobedient.”
—Lawrence Kutner (20th century)
“The hypothesis I wish to advance is that ... the language of morality is in ... grave disorder.... What we possess, if this is true, are the fragments of a conceptual scheme, parts of which now lack those contexts from which their significance derived. We possess indeed simulacra of morality, we continue to use many of the key expressions. But we have—very largely if not entirely—lost our comprehension, both theoretical and practical, of morality.”
—Alasdair Chalmers MacIntyre (b. 1929)