If you could time travel back to the last Ice Age, would you be able to speak with any of your distant ancestors? Well, you probably couldn't discuss the mysteries of the universe, but there might be a few words you could use to make yourself understood.
In research published by the Proceedings of the National Academy of Sciences, Mark Pagel, Quentin D. Atkinson, Andreea S. Calude and Andrew Meade attempt to identify words shared among Eurasia's major language families - implying that they may be relics of an older common tongue. Most words have a "half life," meaning there's 50 percent chance they'll be replaced by a new noncognate word every 2,000 to 4,000 words. But some words - particularly numerals, pronounds and adverbs - tend to last longer.
Using a database of hypothesized ancestor words, the authors looked for words related by sound within the language groups. (An example: The Latin pater is obviously related to the English father.) They found "188 word-meanings for which one or more proto-words had been reconstructued for at least three language families."
The following list of words had cognates within four of the language families:
For the most part, commonly used words seem to decay more slowly, though comparatively rare words like "spit," "bark" and "worm" seem to be exceptions. The authors say the connections among these words provide evidence of a Eurasian "linguistic superfamily that evolved from a common ancestor around 15,000 years ago - slightly before the beginning of the Holocene era.
So you may have some (limited) subjects to talk about with your ancient ancestors after all.