For early humans, the biggest competitors for such prehistoric housing may have been an extinct species of bear larger than the grizzly that lived in Europe during the last glacial period.
Scientists know that Neandertals and cave bears (Ursus spelaeus) once used the same caves in southeastern France during the ice age (1.6 million to 10,000 years ago).
The question has been whether early humans and bears were challenging one another for food and shelter.
Now a new study of ancient bear bones and cave paintings shows that bears and Neandertals were not competing for caves, but instead were trading off with perhaps centuries-long gaps in between.
This seems significant with respect to other work possibly showing that humans may have had some responsibility in the extinction of bears. Need to do more research on this though.