World's Oldest Fossils Found In Australia 85
Dexter Herbivore sends this quote from the Washington Post:
"Scientists analyzing Australian rocks have discovered traces of bacteria that lived a record-breaking 3.49 billion years ago, a mere billion years after Earth formed. If the find withstands the scrutiny that inevitably faces claims of fossils this old, it could move scientists one step closer to understanding the first chapters of life on Earth. The discovery could also spur the search for ancient life on other planets. These traces of bacteria 'are the oldest fossils ever described. Those are our oldest ancestors,' said Nora Noffke, a biogeochemist at Old Dominion University in Norfolk who was part of the group that made the find and presented it last month at a meeting of the Geological Society of America."
Re:Not interesting (Score:5, Informative)
Re:Not interesting (Score:5, Informative)
Re:How Old? (Score:5, Informative)
The article doesn't actually say and the Washington Post just links to the article abstract, but C-14 dating isn't used except for recent material because of its small half-life. There are a wide variety of methods used for older rocks (see here [wikipedia.org]). For instance, rubidium-strontium dating might be used, since rubidium-87 has a half life of 50 billion years. Rubidium-strontium can be used for isochron dating [wikipedia.org] as well, which doesn't require any assumptions about the amount of the daughter nuclide in the sample.
Having said that, I don't have any details on the methods actually used to date rocks in this particular region.