A new study published in Nature Communications reveals that Chihuahuas carry a small but distinct sliver of coyote DNA, likely inherited from ancient interbreeding with wild canines in pre-Columbian Mexico. Researchers at Stanford University, led by geneticist Alexander Ioannidis, discovered these genetic fragments while testing a new software algorithm for analyzing genomic ancestry. The findings suggest that the Chihuahua lineage, traced back to the extinct Techichi dog of the Toltec civilization, includes hybridization events with coyotes long before European contact.
Contemporary Chihuahuas retain roughly 4% of their ancestry from these pre-contact dogs, with the coyote DNA embedded deep within that fraction. The precision of this discovery marks the first time such mixed genetic segments have been pinpointed in modern New World dogs. Identical fragments were also found in the Chinese crested breed, confirming a close evolutionary link between the two.
While the size difference between coyotes and Techichis makes natural mating unlikely, historical records suggest intentional breeding programs in ancient Mexico may have facilitated these unions. Despite the genetic insight, traits like the Chihuahua’s fearless demeanor cannot be solely attributed to coyote blood, as physical and behavioral characteristics are governed by complex genetic interactions.
Source: New York Times Top Stories · Summarized by HeadlinesBriefing