Main techniques dating hominids
Several dating methods exist, depending on different criteria and techniques, and some very well known examples of disciplines using such techniques are, for example, history, archaeology, geology, paleontology, astronomy and even forensic science, since in the latter it is sometimes necessary to investigate the moment in the past in which the death of a cadaver occurred.
Relative dating methods are unable to determine the absolute age of an object or event, but can determine the impossibility of a particular event happening before or after another event of which the absolute date is well known.
Chronological dating, or simply dating, is the process of attributing to an object or event a date in the past, allowing such object or event to be located in a previously established chronology.
This usually requires what is commonly known as a "dating method".
(Any remnant of the past, not just bones, can be considered a fossil.) 3.6 million years ago, a volcano now called Sadiman puffed out a cloud of ash that blanketed the surrounding area.
A light rain then turned the ash into a sort of cement that recorded thousands of tracks of antelopes, rhinos, guinea fowl, and monkeys, as well as the footprints of our ancestors.
The same inductive mechanism is applied in archaeology, geology and paleontology, by many ways.
"Relative" dating involves comparing one object to others to build a chronology.
Scientists currently don't have a technique for dating fossils like Lucy directly, but they can assign these fossils relative dates based on the age of layers of volcanic ash found above and below them.
The ages assigned to these fossils have been obtained through radiometric dating of volcanic rocks interbedded with the fossiliferous sediments.
Such numerical calibrations are crucial to understanding rates and timing of evolutionary change.
K-Ar dating has played a key role in unraveling the temporal patterns of hominid evolution as far back as the first significant discovery of East African australopithecines at Olduvai Gorge in 1959.