Ice Age Explorer (Time Machine #7)

First, the author is the great Dougal Dixon. Second it is about the ice age and prehistoric man, which are both subjects I enjoy. Third, the plot happens to be interesting - your character has to find out what a certain one-horned animal found in cave paintings were - was it really a unicorn?
I took a point away only because of the idea that Neanderthals were cannibals! I happen to think that, even in 1985 when the book was published, that idea was already being dismissed.