This means that dates for the final Neanderthals and for the first human occupations of Europe have been unreliable, fomenting the debate.

Accurate dating is important for putting events and objects in sequence.

Ancient sites in England, Malta, and elsewhere turned out to be older than once thought.

Seriation is a relative dating method that is used to place types of artifacts (or sites with certain artifact types) into a chronological sequence.

This is especially significant when archaeologists have no other dating information.

This dating method is used to date obsidian, a kind of volcanic glass.

Obsidian makes a useful knife blade or cutting tool, and archaeologists have found these tools while excavating settlements such as those of the ancient Maya.The rise and fall of each style helps to date the sites.Any artifact that might reflect stylistic changes, such as pottery or tombstone art, can be dated using this relative method.With this new information, scientists were able to paint a more accurate picture of European prehistory. An absolute dating method tells the excavator the specific date of the material being studied (plus or minus a margin of error).Imagine an archaeologist needs to assign a date to a bone recovered during an excavation.The long overlap provided plenty of time for cultural exchange and interbreeding, he adds.