Extinct Dire Wolf (Canus dirus) Fact Sheet: Behavior & Ecology

Because direct observation of a fossil animal's behavior isn't possible, paleontologists use comparison and contrast with living animals for guidance. Tracks can sometimes reveal further clues to behavior. At a fossil site, the mix of plant and animal species gives clues to the ecosystem of that time and place.

(Van Valkenburgh & Sacco 2002)

• Large numbers of dire wolves preserved at La Brea suggest they lived in large groups.
  • Probably the deposits didn't represent solitary individuals feeding successively
  • More than 3,000 individuals represented in several tar pits.
• Probably monogamous, living in packs like modern gray wolves
  • Male and females' teeth and skeletons are similar (little dimorphism)
  • In modern animals, amount of sexual dimorphism correlates with the animal's breeding system
    • When males' canine teeth much larger, males compete strongly for females and breeding system may be polygamous
    • When both sexes have similar canine teeth, typically have low level of male-male competition and pair-bonded breeding system as in African wild dogs, dholes, gray wolves. 

• Many other species of dog-like carnivores found in fossil sites with dire wolves. (Hodnett et al 2009)
  • Coyotes, timber wolves, Asiatic wild dogs at San Jacinto Cave (Nuevo Leon, Mexico)
  • Coyotes, domestic dogs, gray foxes, and timber wolves at La Brea asphalt deposits
• Lack of tooth wear scratches on Smilodon suggests they many have left large portions of their kills (Van Valkenburgh et al 1990)
  • A co-evolutionary relationship with dire wolves (who could finish eating the kills) proposed by researchers.
• Between 15,000 and 12,000 years ago dire wolves may have undergone changes in feeding habits (Van Valkenburgh & Hertel 1003) (Binder et al 2002)
  • Earlier fossils show more tooth breakage, perhaps signifying more bone-chewing of kills
  • Later fossils (at 12,000) years ago show less bone consumption and less breakage.
  • Less bone consumption most likely reflects less competition with other predators for kills as numbers of all these large animals declined.

Binder et al. (2002)
Hodnett et al. (2009)
Van Valkenburgh et al. (1990)
Van Valkenburgh & Hertel (1993)
Van Valkenburgh & Sacco (2002)