Into the mind of a Neanderthal

Its just a quick little blurb, but think for a moment. What would you look for that would indicate marriage in a society long since gone, and with no historical record?

Many Neanderthal sites have rare pieces of high-quality stone from more distant sources (more than 100 kilometres), but not enough to indicate trade or even regular contact with other communities. A more likely scenario is that an adolescent boy or girl carried the material with them when they attached themselves to a new community. The small size of Neanderthal territories would have made some form of "marrying out" essential.

We can also assume that Neanderthals had some form of marriage because pair-bonding between men and women, and joint provisioning for their offspring, had been a feature of hominin social life for over a million years.

From this article.