The latter is most likely produced by anatomically modern humans.
However, two-thirds of dates from the south are radiocarbon dates, a technique that is particularly sensitive to carbon contaminants of a younger age that can be difficult to remove using routine pretreatment protocols.
Only two, Jarama VI and Zafarraya, were found to contain material that could be reliably dated.
At archaeological sites, identification of charcoal and wood can provide information concerning trees and shrubs growing at or near a particular site, as well as types of wood burned as fuel or used as building materials.
Charcoal also is commonly submitted for radiocarbon analysis.
The dating process is always designed to try to extract the carbon from a sample which is most representative of the original organism.
In general it is always better to date a properly identified single entity (such as a cereal grain or an identified bone) rather than a mixture of unidentified organic remains.