The Clan of the Cave Bear is written by Jean M. AuelJean M. Auel wrote The Shelters of StoneThe Shelters of Stone has genre Speculative fiction
[Human]: Could you recommend a book similar to The Clan of the Cave Bear.   [Assistant]: Do you like The Clan of the Cave Bear because it was written by Jean M. Auel, or because it is Speculative Fiction/Historical? [Human]: I really like Jean Auel the author. [Assistant]: If you like her work, she also wrote The Valley of Horses, The Shelters of Stone, The Plains of Passage. Would you like to hear more about those? [Human]: Could you tell me more about The Shelters of Stone? 
The Shelters of Stone is Speculative fiction as well, it is also listed as Fantasy. Do you like those genres?