Old oceans too hot and salty for evolution, according to an article in New Scientist,, 5 February 2005, p17. Paul Knauth of Arizona State University claims to have calculated the temperature and salinity of the early earth’s oceans and claims that the oceans were warmer than 55 degrees Celsius until 2.5 million years ago when they started to cool down until the oceans were completely frozen over approximately 700 million years ago. In the meantime the salt level of the oceans was about twice as much as the present level until about 600 million years ago. Knauth believes that these hot salty oceans would not have been able to maintain enough dissolved oxygen for sea animals to live in. He believes that animals originally evolved in freshwater ponds and lakes and moved into the oceans after they became more habitable and this migration led to the Cambrian explosion, believed to have occurred about 570 million years ago. Knauth is now searching for freshwater fossils that would support his ideas, but has not found any yet.

Editorial Comment: Even if the water in the early Earth’s oceans was the right temperature with the right amount of salt, life would not spontaneously arise from it. The complex molecules in living cells can be made from the common chemicals in the environment, but only if there is complex cellular machinery and instructions from genetic code already in existence. Darwin also suggested that life originated in a “warm little pond” and he also noted that lack of fossil evidence was one of the greatest difficulties for his theory. Perhaps it is time they admitted defeat? (Ref. environment, chemical evolution, oceans)