Sept. 1 (UPI) -- The New Guinea singing dog was thought to have disappeared from the wild some 50 years ago, but new research suggests the unusual species has been thriving all along in the New Guinea Highlands.
Genomic analysis, detailed this week in the journal Proceedings of the National Academy of Science, confirmed a group of wild dogs discovered in the New Guinea Highlands as the population from which New Guinea singing dogs were derived.
New Guinea singing dogs are noted for their distinct, melodious howls.
"Canids make all kinds of sounds, but the sound that New Guinea singing dogs make is different, it's unlike any dog sound you've heard," Elaine Ostrander told UPI on Tuesday.
"It has a harmonic, tonal quality that goes up and goes down in pitch," said Ostrander, lead investigator at the National Human Genome Research Institute of the National Institutes of Health.
Knowledge of the New Guinea singing dog can be traced back in the scientific literature to the 19th century, but by the 1970s, scientists reported the dog missing from the wild.
In an effort to conserve the species, a handful of dogs were brought from conservation centers in New Guinea to the United States. On the surface, the effort was a success, breeders turned eight or nine dogs into a population of nearly 300.
"The problem is that when you start with just eight or nine dogs and you breed them and breed them, you lose genetic diversity very quickly," Ostrander said.
In the mid-2000s, word spread of a group of dogs in the mountains of Indonesia that resembled New Guinea singing dogs. James McIntyre, president of the New Guinea Highland Wild Dog Foundation, led a pair of expeditions to find and document the wild dogs. On the second expedition, in 2018, McIntyre was able to obtain blood samples.
Back in the lab, scientists were able to isolate the nuclear genomes of three individual dogs from DNA in the blood samples.
"When we looked at the highland dogs' genome and compared it to all known dog breeds from everywhere in the world, as well as to dingoes and village dogs from New Guinea, it was clear that they were most closely related to New Guinea singing dogs," Ostrander said.
The findings also allowed researchers to measure the loss of genetic diversity the New Guinea singing dog experienced while in captivity, data that could help conservation biologists improve future captive breeding programs and protect species vulnerable to genetic bottlenecking.
Often, captive breeding programs start with only a small sample of a popualion's genetic diversity.
"Those eight or nine dogs were all taken from around the same area, so chances are that they were probably fairly closely related," Ostrander said. "By the time a species is a candidate for a captive breeding program, they are undergoing duress and have already lost some genetic diversity."
Researchers hope the wild dogs of the New Guinea Highlands can help conservationists restore the genetic diversity of the New Guinea singing dog.
Ostrander said he hopes a more complete picture of the New Guinea singing dog's genome could help her and her colleagues locate the genes responsible for the dog's unique singing ability.
"That's something I'm personally very interested in finding out," she said. "Then I'd like to know what these same genes are doing in humans. Nature is very clever about redundancy, it will often use the same genes for slightly different things."
The new findings could also have implications for the complex and still poorly understood story of dog domestication.
"When we build a tree of all the canids, we find that New Guinea Highland wild dogs, New Guinea singing dogs and dingoes all tie closely together on a branch, and that branch came off pretty early on, well before the emergence of all the other kinds of dog breeds we know today," Ostrander said. "But where [the New Guinea singing dog] falls into the story of domestication is something we can't say for certain. We need to do more research in order to better understand it."