Answers are grounded in this paper and cite their sources.
It is a startling experience to look down a microscope at a stone tool — a real Palaeolithic artefact, not a modern thing or a replicated copy — and see on its flint surface grubby brown-red stains that look the colour of old blood. Is a consensus emerging from the archaeological scientists as to just what traces of, especially, biological materials do survive on ancient stone surfaces, where they can be reliably characterized and identified?
No takes yet. Share an insight, caveat, or question.
Fullagar et al. (1996) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: