Silhouette of the artist's hand - often found repeated a number of times.

A form of 'signature' or other expression of an independent ego? This may be so, but more archeologists theorize prehistoric culture had no real sense of individual identity, certainly not as we understand the concept.

Some dismembered hands appear to be part of a ritual of some sort, but most appear to be victims of frostbite in this, the end of the glacial period.
Notice how the silhouette is created in a 'niche' area of this outcropping of rock - certain 'areas' seemed to be particularly inviting for the artist, perhaps for some symbolic or suggested artistic reason.