Coywolf

Genomic studies indicate that nearly all North American gray wolf populations possess some degree of admixture with coyotes following a geographic cline, with the lowest levels occurring in Alaska, and the highest in Ontario and Quebec, as well as Atlantic Canada.

Executive Director Peggy Callahan at the facility states that the howls of these hybrids are said to start off much like regular gray wolves with a deep strong vocalization, but changes partway into a coyote-like high pitched yipping.

[12] Their range also occurs in the Canadian provinces of Ontario, Quebec, New Brunswick,[13] Nova Scotia,[14] Prince Edward Island and Newfoundland and Labrador.

The addition of domestic dog genes may have played a minor role in facilitating the eastern hybrids' adaptability to survive in human-developed areas.

[18] The four-in-one hybrid theory was further explored in 2014, when Monzón and his team reanalyzed the tissue and SNP samples taken from 425 eastern coyotes to determine the degree of wolf and dog introgressions involved in each geographic range.

Urban environments often favor coyote genes, while the ones in the rural and deep forest areas maintain higher levels of wolf content.

[25] In 2016, a whole-genome DNA study suggested that all of the North American canids, both wolves and coyotes, diverged from a common ancestor 6,000–117,000 years ago.

The experiment, which used artificial insemination, was intended to determine whether or not the sperm of the larger gray wolves in the west was capable of fertilizing the egg cells of western coyotes.

[3] In 2015, a research team from the cell and microbiology department of Anoka-Ramsey Community College revealed that an F2 litter of two pups had been produced from two of the original hybrids.

[30] The study also discovered through sequencing 16S ribosomal RNA encoding genes that the F1 hybrids all have an intestinal microbiome distinct from both parent species, but which was once reported to be present in some gray wolves.

Moreover, analysis of their complementary DNA and ribosomal RNA revealed that the hybrids have very differential gene expressions compared to those in gray wolf controls.

[32] Hence, coydogs are another biological sub-variation of hybrids between coyotes and gray wolves - the dog being considered a domesticated subspecies of Canis lupus.