Different studies often report substantial discrepancies between age estimates for groups of organisms implied by the fossil record and estimates generated by molecular clocks. (sciencedaily.com)
Radio - carbon dating is a method of obtaining age estimates on organic materials. (myintimcity.com)
The case involved a mentally disabled woman, in her early 20's, with a cognitive / social / emotional clinical age estimated to be equivalent to that of an 8 year old. (slaw.ca)