Fast tidal cycling and the origin of life |
| |
Authors: | Richard Lathe |
| |
Affiliation: | a Department of Biomedical Sciences, University of Edinburgh, George Square, Edinburgh EH8 9XD, UK b Pieta Research, PO Box 27069, Edinburgh EH10 5YW, UK |
| |
Abstract: | Replicating prebiotic polymers are thought to predate the emergence of true life-forms. The initial mode of replication, a prerequisite for Darwinian selection, is unknown, but demands an explanation based on local physicochemistry. Dual consideration of the conditions of the early terrestrial surface, with the unusual physicochemical properties of nucleic acids like DNA, could explain the emergence of nucleic acids as key biomolecules. The early impact that produced the Moon, and fast terrestrial rotation, subjected coastal areas 3.9 Ga ago to rapid tidal flooding (dilution) and drying (concentration), with a likely periodicity in the range of 2-6 h, and could have provided a driving force for cyclic replication of early biomolecules. Such a mechanism applies only to molecules capable of association/polymerization at high salt concentration, and of dissociation at low salinity. Nucleic acids meet these criteria. It is suggested that tidal cycling, resembling the polymerase chain reaction (PCR) mechanism, could only replicate and amplify DNA-like polymers. This mechanism suggests constraints on the evolution of extra-terrestrial life. |
| |
Keywords: | Origin Life DNA Nucleic acid PCR Moon Tide Cycling Salinity |
本文献已被 ScienceDirect 等数据库收录! |
|