Late Pleistocene Predators.

The following is speculation pure and simple, but based on narrow science discoveries with a lot of help from the speculations of Jon Franklin in The Wolf in the Parlor .
Neanderthals were well adapted as European top predators in the late Pleistocene strong, large brained, robust and skillful hunters of large game.  They may even have preyed on Homo Sapiens, at least they toyed with Homo sapiens women.  Neanderthal DNA in the main H. Sap. genome with no mitochondrial DNA from Neanderthals would indicate that the preying was all one way.  It would seem that Homo sapiens mostly stayed out of their way where the ranges overlapped.

The other major top predator, particularly of smaller game that was probably the primary meat source of H. Sap was the wolf.    Wolves were skillful pack hunters and based on the ancient stories of wolf predation on humans may have been the primary predator of humans.   But some of the wolves apparently lost the pack hunting skills/instincts of other wolves and began to hang around human habitations.  Living on the abundant garbage of the frequently moving humans.  These "follower wolves" presumably also prey of wolf packs developed a herd type organization with a bark instead of a howl to warn of predators.  This predator warning was also useful to the humans who could respond intelligently to threats.  Over time Franklin speculates that the more docile of the follower wolves were co-opted as herd protectors, and most important as baby sitters and companions for the elderly and infirm.  An instinct/skill retained from the pack wolves.

The combined skills of the human-dog symbiote as Franklin speculates were critical in becoming the top predator in the Late Pleistocene.  I  suspect the extinction of the big game for whatever reason either over hunting by Neanderthals or climate change eliminated them from the comfortable niche they dominated, but the wolves remained as a major contender for the top spot.