My old Smithsonian buddy and fellow traveler Carl Hansen sent me this photo of a pot-bellied green-eyed dog, which he camera-trapped in West Virginia.
This ain't no good-old boy's hound, and if I met it in the woods you wouldn't catch me calling "Nice puppy, c'mon boy".
There's a good chance this is a dog-coyote cross, or a coydog.
It's an unusual find considering that only one of 24 West Virginia coyotes (4.2%) were found to have dog ancestry as indicated by the la24
haplotype.
A haplotype is a genetic sequence of DNA that is inherited as a unit, and is thus easily identified as a genetic marker.
A few pioneers of the American West mentioned Indian dogs that resembled coyotes, but commingling of coyotes and dogs was probably rare during the first 15,000 years of their coexistence in North America.
Coydogs don't pop up in the literature until the 1930s, when the great northwoodsman-naturalist Olaus Murie bred a tame female coyote with a dog.
The coyote aborted the fetus which raised a question about the viability of dog-coyote crosses.
In the 1940s academic naturalists started to notice strange looking coyotes.
In 1941 for example the late mammalogist E. Raymond Hall and his wife saw a strange looking canid at the zoo in Custer State Park.
It had a reddish ruff on its chest and lower neck.
As Hall was pondering the animal a 10-year old boy pedaled up on a bike.
Evidently with no small measure of pride he announced that it was a cross between his wire-haired fox terrier and a captive female coyote.
When Hall got back to UC Berkeley he wrote to the zoo's director and requested the hybrid animal's skull, and 9 months later it arrived in the mail.
He compared the zoo specimen with skulls of a coyote and a dog and concluded that "the resemblance to the coyote are about twice as pronounced as to the dog".
Hall questioned the viability of the crosses, and noted that red wolves were also intermediate between the wolf and coyote "in morphological characters and in geographic range..."
Actually, the ecologist-geneticist Lee R. Dice had already hybridized domestic mongrels and hounds with coyotes at the University of Michigan's George Reserve.
His male coyote halfheartedly mounted estrous dogs, and Dice conceded that bears in a nearby pen might have dampened his coyote's ardor.
The dogs however showed no such inhibitions to a coyote bitch in heat, and 3 pups issued from the union.
They grew into big-footed, lop-eared and short-haired animals that resembled dog or coyote to varying degrees.
Two of them yipped like coyotes and the other barked like a dog, but all three lacked the "quick, agile movements of the coyote. . . , and were rather quarrelsome".
The premature death of two of the pups and the abnormal development of the male's testes nurtured the notion that dog-coyote hybrids were sterile.
In December 1948, however, Mr Edward Revey shot three wild canids on the Graybill pasture in Franklin County, Kansas.
Since they were big and had reddish coats, Revey thought they were hybrids.
Mrs Iva Hunzicker, who lived down the road thought her "red dog" was their daddy.
Old Red, a German shepherd-black and tan coon hound cross, was prone to cavort with coyotes.
Revey delivered the bodies of red dog's presumptive progeny to the University of Kansas's Museum of Natural History, where they were processed for the mammal collection.
In due course Professors James Bee and E. Raymond Hall examined the skulls and skeletons, and compared them with domestic dogs, coyote, gray wolf, and red wolf.
They sorted the canids on a continuum based on the average of 4 measures -- three skull indices and the angle of the eye socket.
The domestic dog and coyote were at opposite ends of the continuum, while Old Red's presumptive offspring and the red and gray wolves were intermediate.
They concluded that the three red dogs "were indeed hybrids between the domestic dog and the coyote", but they bowed to Dice's surmise that male hybrids are infertile, noting as supportive evidence that F2 offspring of coyote-dog crosses were unknown.
It took another 12 years for someone to look into the F2 question.
That's when Robert Mengel started a coyote and dog breeding project at the University of Kansas.
The progeny of a mongrel terrier bitch and a hand-reared coyote named Jose produced offspring that looked like "short-haired, short-legged melanistic coyotes with white-trimmed chins, feet, tail tips, and a white blaze on the chest".
The outlier was a longer-haired bitch that had a vizor of hair over its eyes like the mother.
Brother-sister matings produced an even more variable-looking F2 generation. They were aggressive and killed a visiting pet coyote.
The hybrids acquired the seasonal breeding pattern of coyotes but oddly they were 3 months out of phase -- coming into season from October to December rather than January-March as in coyotes.
This has a serious consequence for perpetuating further crosses between coyotes and coydogs.
It simply isn't possible unless the odd coydog inherits the normal coyote reproductive cycle.
Coydogs face another obstacle to survival -- they aren't as tough as coyotes when it comes to weathering subfreezing temperatures.
Despite the ominous odds, reports and specimens of suspected coydogs continued to accumulate over the next two decades.
In Nebraska for example, they emanated mainly from centers of human and domestic dog populations.
Awareness of strange looking wild canids continued to spread to the eastern US.
The most recent generation of investigators have tackled the problem with more decisive tools -- DNA analysis.
The crossing of coyotes, wolves and domestic dogs is an evolutionary work in progress, and the pot-bellied green-eyed West Virginian is part of the story.
Carol Kaesuk Yoon covers the rest of the hybridization story in
Mysteries that Howl and Hunt.
Be sure to read it.
References
Adams, J.R., J.A. Leonard, and L.P.Waits. 2003. Widespread occurrence of a domestic dog mitochondrial DNA haplotype in southeastern coyotes.
Molecular Ecology, 12, 541-546.
Bee, J.W. and E.R. Hall. An instance of coyote-dog hybridization.
Transactions of the Kansas Academy of Sciences, 54(1):73-77.
Dice, L.R. 1942. A family of Dog-Coyote hybrids.
Journal of Mammalogy, 23(2):186-182.
Hall, E.R. 1943. Cranial characteristics of a Dog-Coyote hybrid.
American Midland Naturalist, 29(2):371-374.
Kays, R., A. Curtis, and J.J. Kirchman. 2010. Rapid adaptive evolution of northeastern coyotes via hybridization with wolves.
Biology Letters, 6:89-93.
Mahan, B.R., P.S. Gipson, and R.M. Case. Characteristics and distrIbution of Coyote X Dog Hybrids collected in Nebraska.
American Midland Naturalist, 100(2):408-415.
Mengel, R.M. 1971. A study of dog coyote hybrids and implications concerning hybridization in Canis.
Journal of Mammalogy, 52:316-336.
Murie, O.J. 1936. Dog skulls from St. Lawrence Island, Alaska. Misc. Publ. Univ. Alaska, 2:347-357.
