Despite their long history of domestication, cats, unlike domestic dogs, are still quite able to resort to a self-reliant lifestyle if needed. This is believed to be primarily due to the fact that cats, which are solitary animals in nature, have never been subjugated to the extent of canine species, which are pack animals that naturally defer to a leader. Dogs have also been domesticated for a much longer period of time than cats, their relationship with man beginning as many as 50,000 years ago.