ASSESSMENT OF TECH NOTE ISSUED BY THE UNITED STATES DEPARTMENT OF AGRICULTURE ON APRIL 2016, REGARDING A NEW INTERPRETATION

OF THE CLASSIFICATION OF NEW GUINEA SINGING

DOGS AND AUSTRALIAN DINGOES

 

Prepared For: Maya Lopez Grasse, Alston & Bird LLP

Prepared By:   Susan Bowers

Date:               May 13, 2016

 

Dear Dr. Carter-Corker and Colleagues,

 

This past April, the USDA published an Animal Care Tech Note regarding a new interpretation on the status and handling of captive-bred New Guinea singing dogs and Australian dingoes. I have reviewed the note carefully, and would like to express my concerns about the technical soundness of this reclassification, and its possible repercussions. Thank you for being willing to revisit this issue!

 

Whether the dingo breeds are considered Canis familiaris, C. f. dingo, Canis lupus familiaris, C. l. dingo, or other subspecies seems to be a matter of uncertainty at this time. The preferred taxonomy of these dogs is likely to change again, probably more than once, in the very near future, as the currently accumulating DNA research becomes published. Given that, the most important factor from my perspective is that Australian and New Guinea's aboriginal dogs are grouped accurately with the rest of the genetically divergent basal breeds, with C. lupus dingo (and any future incarnations) being acknowledged as a synonym for Canis [lupus] familiaris, the domestic dog.

 

Current DNA-testing results, phenotypes, historical data, and ethology all consistently agree on the fact that the indigenous dingo "breeds" are previously-domesticated dogs, who migrated to Australia and New Guinea from southeast Asia. Their dog heritage is not in dispute. Upon returning to a free-living state, village dogs and dingoes reverted to the typical 'long-term pariah morph' type, tailored to their specific climate and environment, as dogs have done on every continent except Antarctica. They have retained their state of domestication, as evidenced by their domestic morphological traits and full array of human-centric inborn behaviours. Australian dingoes (AUD) and New Guinea singing dogs (NGSD) possess genetic signatures, physical traits, and behaviours that are well within the continuum of domestic dogs as a whole. Additionally, all of the similar breeds and village dogs also have East Asian genetic origins, population bottlenecks, and subsequent isolation that led to their distinct genetic signatures and pariah dog morphology.

 

Presently, available taxonomic registries list C. l. dingo as synonymous to the [domestic dog].  Here are current listings for the NGSD and Australian dingo, on various registries. (Screen captures for these listings are included in the attached files, along with all relevant documents from the bibliography.)

 

ITIS report[1] (official website):  Canis lupus dingo [domestic dog]

Mammal Species of the World[2] (official website):  Canis lupus dingo [domestic dog]

American Society of Mammalogists[3]: (official website)  Canis familiaris – Domestic Dog (Dingo)

Australian Faunal Directory[4]: (official website)  Species: Canis familiaris.  Common Dog, Dingo, Domestic Dog

 

The large assortment of available DNA studies clearly shows the descent of ancestral breeds (including the AUD and NGSD) from East Asian domestic dogs; there is no controversy over their lineage. I'd like to present a few of the most relevant genetic studies, along with a field research paper, to demonstrate that the Australian dingo and New Guinea singing dog—along with their counterparts in other geographic areas—are of domestic dog descent, and fall consistently within the genetic range of dogs. Their haplotypes are notably distinct from those of wild canids.  Please see the following papers:

 

Genome-wide SNP and haplotype analyses reveal a rich history underlying dog domestication.[5] (vonHoldt, 2010)

Neighbour-joining trees reveal that most of these breeds (basenji, Afghan hound, Samoyed, saluki, Canaan dog, New Guinea singing dog, dingo, chow chow, Chinese Shar Pei, Akita, Alaskan malamute, Siberian husky and American Eskimo dog) are highly divergent from other dog breeds.

 

A detailed picture of the origin of the Australian dingo, obtained from the study of mitochondrial DNA.[6] (Savolainen, 2004)

To determine the origin and time of arrival to Australia of the dingo, 582 bp of the mtDNA control region were analyzed in 211 Australian dingoes sampled in all states of Australia, 676 dogs from all continents, and 38 Eurasian wolves, and 263 bp were analyzed in 19 pre-European archaeological dog samples from Polynesia. We found that all mtDNA sequences among dingoes were either identical to or differing by a single substitution from a single mtDNA type, A29. This mtDNA type, which was present in >50% of the dingoes, was found also among domestic dogs, but only in dogs from East Asia and Arctic America, whereas 18 of the 19 other types were unique to dingoes. The mean genetic distance to A29 among the dingo mtDNA sequences indicates an origin ≈5,000 years ago. From these results a detailed scenario of the origin and history of the dingo can be derived: dingoes have an origin from domesticated dogs coming from East Asia...

 

Mitochondrial DNA data indicate an introduction through Mainland Southeast Asia for Australian dingoes and Polynesian domestic dogs.[7] (Oskarsson, 2011)

...dogs were one of three domesticates brought with the colonization of Polynesia, but the introduction routes to this region remain unknown. This also relates to questions about human history, such as to what extent the Polynesian culture was introduced with the Austronesian expansion from Taiwan or adopted en route, and whether pre-Neolithic Australia was culturally influenced by the surrounding Neolithic world. We investigate these questions by mapping the distribution of the mtDNA founder haplotypes for dingoes (A29) and ancient Polynesian dogs (Arc1 and Arc2) in samples across Southern East Asia (n = 424) and Island Southeast Asia (n = 219). All three haplotypes were found in South China, Mainland Southeast Asia and Indonesia but absent in Taiwan and the Philippines, and the mtDNA diversity among dingoes indicates an introduction to Australia 4600–18 300 years BP.

 

Wild dogs and village dogs in New Guinea: Were they different?[8] (Dwyer, 2016)

In early reports from coastal lowland New Guinea, at Bosavi in 1966, at Gwaimasi in 1986-87 and to a lesser extent at Suabi in 2011-14 most village-based dogs corresponded in a number of morphological and behavioural attributes to features that have been highlighted in accounts of high altitude, purportedly wild-living, New Guinea dogs. These include size, colour and markings, the presence of a tail brush, tail flagging, climbing ability, howling and chorusing. None of these attributes distinguishes village dogs at any altitude of New Guinea from wild-living dogs....

Most recently, Jackson and Groves (2015: 288), urging 'caution about applying formal scientific names to introduced populations', consider that the trivial names dingo, papuensis and hallstromi should be treated as synonyms of familiaris. They argue, further, that subspecific labelling within C. familiaris is unwarranted on the grounds 'of a general acknowledgement that a domestic species cannot have subspecies because these could not be geographic segments of the species as they have no natural distribution'.

 

Narrow genetic basis for the Australian dingo confirmed through analysis of paternal ancestry.[9] (Ardalan, 2012)

Studies of mitochondrial DNA (mtDNA) imply that the current dingo population was founded by a small population of already tamed dogs from Southeast Asia. However, the maternal genetic data might give a unilateral picture, and the gene pool has yet to be screened for paternal ancestry. We sequenced 14,437 bp of the Y-chromosome (Y-chr) from two dingoes and one New Guinea Singing Dog (NGSD). This positioned dingo and NGSD within the domestic dog Y-chr phylogeny, and produced one haplotype not detected before. With this data, we characterized 47 male dingoes in 30 Y-chr single-nucleotide polymorphism sites using protease-mediated allele-specific extension technology. Only two haplotypes, H3 and H60, were found among the dingoes, at frequencies of 68.1 and 31.9 %, respectively, compared to 27 haplotypes previously established in the domestic dog. While H3is common among Southeast Asian dogs, H60 was specifically found in dingoes and the NGSD, but was related to Southeast Asian dog Y-chr haplotypes. H3 and H60 were observed exclusively in the western and eastern parts of Australia, respectively, but had a common range in South-east. Thus, the Y-chr diversity was very low, similar to previous observations for d-loop mtDNA. Overall genetic evidence suggests a very restricted introduction of the first dingoes into Australia, possibly from New Guinea. This study further confirms the dingo as an isolated feral dog.

 

The study also notes that Australian dingoes most likely originated from a very small founder population of New Guinea singing dogs.

 

This extensive genetic sharing indicates an origin of dingoes via New Guinea. The fact that all dingoes share a single mtDNA founder haplotype while there are several mtDNA haplotypes present in today’s Indonesia and New Guinea also suggests that this was the only introduction route of dogs to Australia, since introductions of dogs from multiple regions into Australia should have brought several different mtDNA founder haplotypes.  (Ardalan, 2012)

 

Multiple and Ancient Origins of the Domestic Dog.[10] (Vila, 1997)

All analyses supported a grouping of dog haplotypes into four distinct clades, although the topology within and among clades differed among trees (13). As exemplified by the neighbor-joining analysis (Fig. 2A), three of the four monophyletic clades defined a larger clade containing all but three dog haplotypes and a subset of wolf haplotypes (W4 and W5). Clade I included 19 of the 26 dog haplotypes. This group contained representatives of many common breeds as well as ancient breeds such as the dingo, New Guinea singing dog, African basenji, and greyhound (14). Clade II included dog haplotype D8, from two Scandinavian breeds (elkhound and jämthund), and was closely related to two wolf haplotypes found in Italy, France, Romania, and Greece (W4 and W5). Clade III contained three dog haplotypes (D7, D19, and D21) found in a variety of breeds such as the German shepherd, Siberian husky, and Mexican hairless. Finally, clade IV contained three haplotypes (D6, D10, and D24) that were identical or very similar to a wolf haplotype (W6) found in Romania and western Russia, which suggests recent hybridization between dogs and wolves.

 

Genome Sequencing Highlights the Dynamic Early History of Dogs.[11] (Freedman, 2014)

To investigate dog origins, we sequence three wolf genomes from the putative centers of origin, two basal dog breeds (Basenji and Dingo), and a golden jackal as an outgroup. We find that none of the wolf lineages from the hypothesized domestication centers is supported as the source lineage for dogs, and that dogs and wolves diverged 11,000–16,000 years ago in a process involving extensive admixture and that was followed by a bottleneck in wolves. In addition, we investigate the amylase (AMY2B) gene family expansion in dogs, which has recently been suggested as being critical to domestication in response to increased dietary starch. We find standing variation in AMY2B copy number in wolves and show that some breeds, such as Dingo and Husky, lack the AMY2B expansion. This suggests that, at the beginning of the domestication process, dogs may have been characterized by a more carnivorous diet than their modern day counterparts, a diet held in common with early hunter-gatherers.

 

Rethinking dog domestication by integrating genetics, archeology, and biogeography.[12] (Larson, 2012)

To ascertain the value of modern genetic data to elucidate the origins of dog domestication, we analyzed 49,024 autosomal SNPs in 1,375 dogs (representing 35 breeds) and 19 wolves. After combining our data with previously published data, we contrasted the genetic signatures of 121 breeds with a worldwide archeological assessment of the earliest dog remains. Correlating the earliest archeological dogs with the geographic locations of 14 so-called “ancient” breeds (defined by their genetic differentiation) resulted in a counterintuitive pattern. First, none of the ancient breeds derive from regions where the oldest archeological remains have been found. Second, three of the ancient breeds (Basenjis, Dingoes, and New Guinea Singing Dogs) come from regions outside the natural range of Canis lupus (the dog’s wild ancestor) and where dogs were introduced more than 10,000 y after domestication. These results demonstrate that the unifying characteristic among all genetically distinct so-called ancient breeds is a lack of recent admixture with other breeds likely facilitated by geographic and cultural isolation. Furthermore, these genetically distinct ancient breeds only appear so because of their relative isolation, suggesting that studies of modern breeds have yet to shed light on dog origins.

We conclude by assessing the limitations of past studies and how next-generation sequencing of modern and ancient individuals may unravel the history of dog domestication.

 

As discussed above, many basal breeds have also experienced severe bottlenecks that have exaggerated their unique genetic signatures. The extant captive population of the New Guinea Singing Dog is descended from only eight individuals... (Larson, 2012)

 

The most predictive factor in determining whether a breed retains a basal signature is a lack of gene flow, or at least a lack of introgression with breeds that do not possess basal signatures. Thus, the unifying characteristic among the 14 basal dog lineages (Table 1) is geographic or cultural isolation from the primary center of dog breeding in Europe that began in the 19th century. (Larson, 2012)

 

Village dogs have also been tested, and found to be “genetically distinct”.

 

Phylogenetic Distinctiveness of Middle Eastern and Southeast Asian Village Dog Y Chromosomes Illuminates Dog Origins.[13] (Brown, 2011)

We sampled 9 wild canids and 633 dogs for this study, including 480 village dogs (300 males) from the Middle East and Southeast Asia, 15 Australian dingoes (5 males), 45 desert-bred Salukis (31 males), and 93 male breed dogs from 35 additional breeds or mixtures of breeds. Blood, tissue, or buccal swabs were obtained from the wild canids, including gray wolves from Iran (n= 3), China (n =1), and the Yukon, Canada (n= 3), along with a blackbacked jackal (Canis mesomelas) and a dhole (Cuon alpinus) from captivity. Buccal swabs were collected from dogs. Most village dogs (mainland and Island Southeast Asia) were captured in the course of spay-neuter programs (Figure S1). Middle Eastern village dogs were sampled from Iran (Shiraz, n = 180; Kerman, n= 31; Kazerun, n= 22) along with desert-bred Salukis from Israel

(n= 45). Roughly a quarter of the Southeast Asian village dogs were from the mainland (i.e., Thailand, n= 57), directly south of where Pang et al. [14] hypothesized dogs were domesticated. The remainder were from Islands in Southeast Asia: Taiwan (n= 40), Brunei (n= 27), Bali (n= 97), and the Philippines (n= 26), along with 15 dingoes from Fraser Island, Australia....

 

Please see attached graphics [brown 2011 clades.png] and [brown 2011 clades2.png] which show dingo DNA results clustering with dogs from Southeast Asia, and separate from wild canids.

 

Genetic structure in village dogs reveals a Central Asian domestication origin.[14] (Shannon, 2015)

We also see indigenous Mt haplotypes segregating in Carolina dogs and Xoloitzcuintlis, but no unique Y haplotypes indicative of indigenous ancestry were found in American dogs outside of the Arctic. Alaskan village dogs and Arctic breeds form a cluster based on nuclear markers, whereas other American dogs show little, if any, non-European ancestry, except for Carolina dogs, which contain between 10% and 35% pre-Columbian ancestry based on clustering with East Asia (SI Appendix, Fig. S12). Fijian and French Polynesian dogs also retain little indigenous ancestry (Fig. 4) and contain only universal Y and Mt haplotypes. Nevertheless, these dogs are clearly genetically distinct (Fst = 0.01–0.04 between island groups), with additional genetic structure within both countries (SI Appendix, Table S8), suggesting genetic drift has occurred on these islands since the introduction of European dogs. In contrast, Papua New Guinea and Solomon Island dogs retain a mix of European and indigenous ancestry (68–78% and 78–86% European ancestry, respectively; SI Appendix, Table S6), whereas Borneo dogs have no detectable European ancestry and are only moderately differentiated from Vietnamese dogs (Fst =0.05). African dogs have indigenous ancestry components and European admixture. African ancestry components reflect geography,with Basenjis containing two components reflecting Benin and Democratic Republic of Congo (DRC) imports...

 

In a nutshell, the driving force behind all of the basal dog lineages is geographic isolation from the influx of modern European dogs.  Many of those breeds also experienced population bottlenecks that concentrated their genetic signature. (The process is actually very similar to modern dog breeding, except that dogs were selected by the environment for survival traits, rather than for traits appealing to humans, such as size, color, or an enhanced ability to point or retrieve.)

 

The process of domestication produces lasting physical change. Dogs that revert to feral do not turn back into the wolf. The process of speciation generally takes hundreds of thousands of years to accomplish; certainly the few thousand years that dogs have been inbreeding amongst themselves is nowhere near enough to create a new animal. In the meantime, those dogs have lived alongside humans; the Australian dingo is documented as being bred in captivity as companion dogs for more than 100 years, and probably far longer. According to in-depth research by experts:

 

Dingoes and Aboriginal social organization in Holocene Australia.[15] (Balme, 2015)

Dogs are perhaps the most widespread domesticated animal and the species that forms the closest bonds with humans. Placental dogs (dingoes) appear in the Australian record in the mid to late Holocene and, at European contact just over 200 years ago, tamed dingoes were observed to be living with Aboriginal people. These dingoes were used as companions, protectors and as hunting dogs.

 

Singing dogs and village dogs have been documented as hunting aids in New Guinea as well.  The practice continues to this day. The NGSD has been bred in the US for approximately as long as the Basenji, Canaan, and Japanese Shikoku dogs, and longer than the Korean Jindo or Carolina Dog.  Both NGSD and AUD are routinely kept successfully as household companions; in fact, research suggests that there are more Singers kept as pets, than are maintained in zoos!  (Anecdotally, they are often easier to live with than many of the pedigreed Asian dogs.) Several dog registries still list the NGSD. The Australian national kennel club registers AUD [see attached pdf file], and there are records of AUD shown at English dog shows over a century ago.

 

Any behaviours assumed to be specific to the dingo breeds, such as seasonal estrus, male parental involvement, lack of barking, the ability to climb trees, independence, high intelligence, and so forth have also been demonstrated in other domestic dogs. Likewise, both feral and domestic dogs are known to regurgitate food for their pups, when solicited by mouth-licking. (To keep the size of this correspondence down, I have not included documentation on these behaviours, but the data is readily available in publications and videos online.)

 

The official taxon of various canids will continue to change with the latest research, especially with the canine genome now being mapped at an accelerating rate.  Rather than re-examine the status and care standards with every reclassification, I propose that all landraces (including dogs like the dingo breeds, Indian Native dogs, African village dogs, Thai street dogs, and indigenous Chinese breeds) continue to be included with the rest of the ancient/basal breeds, such as the Basenji, husky, Canaan dog, Saluki, and so on, with whom they share the same genetic code. These animals thrive as human companions, and even in facilities it does them a disservice to be treated as wild animals and deprived of walks, offsite adventures and extensive human contact. Furthermore, restrictive labeling could cause serious and unwarranted problems for dogs currently living in homes.

 

Please don't misunderstand my intent; I do not wish to send the message that geographically distinct strains of dog are not scientifically and historically valuable!  However, these ancestral dogs that are largely unmodified by admixture with European cultured breeds are, in every way, still domestic dogs...and their classification should be interpreted as such. As someone who has worked extensively with both the Australian and New Guinea dingo, along with numerous wolves, wolf-dog crosses, coyote crosses, foxes, and many different breeds of dog over the last 16 years, I am well versed in the differences between primitive dogs and their wild counterparts, and feel confident that any further research will support the “domestic companion dog” designation. AUDs and NGSDs are gentle and inhibited dogs who exhibit no behaviours not commonly found in other dogs, and pose no singular risk to the public. The currently existing dog regulations are more than sufficient to manage them.

 

As we ride the ever-changing tide of reclassifications, it would be very beneficial for research, companionship, and the well-being of the dogs themselves, if your organisation would formally modify its interpretation to acknowledge that, regardless of prevalent taxonomic preference, all indigenous dogs are clearly still "dogs" and do not warrant subspecies-specific regulation by the USDA or any similar agency.

 

If I can be of any further use, please don't hesitate to contact me at solowolf_93@yahoo.com or (336) 501-8752.

 

Thank you for your time and effort!

Sue Bowers

 

Works Cited

Ardalan. (2012). Narrow genetic basis for the Australian dingo confirmed through analysis of paternal ancestry. Genetica .

Balme. (2015). Dingoes and Aboriginal social organization in Holocene Australia. Journal of Archaeological Science: Reports .

Brown. (2011). Phylogenetic Distinctiveness of Middle Eastern and Southeast Asian Village Dog Y Chromosomes Illuminates Dog Origins. PLoS ONE.

Dwyer. (2016). Wild dogs and village dogs in New Guinea: Were they different? Australian Mammology.

Freedman. (2014). Genome Sequencing Highlights the Dynamic Early History of Dogs. PLOS Genetics .

Larson. (2012). Rethinking dog domestication by integrating genetics, archeology, and biogeography. Proceedings of the National Academy of Sciences .

official website. (n.d.). Retrieved from http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=726820

official website. (n.d.). Retrieved from http://vertebrates.si.edu/msw/mswcfapp/msw/taxon_browser.cfm?msw_id=11387&CFID=5084850&CFTOKEN=14410530&jsessionid=7e30a142117d66d6620c6f747113647cb1b2

official website. (n.d.). Retrieved from http://www.mammalsociety.org/uploads/LIST%20OF%20IMAGES%20IN%20MAMMAL%20IMAGES%20LIBRARY%2001-31-2016.pdf

official website. (n.d.). Retrieved from http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/afd/taxa/Canis_familiaris

Oskarsson. (2011). Mitochondrial DNA data indicate an introduction through Mainland Southeast Asia for Australian dingoes and Polynesian domestic dogs. . Proceedings of the Royal Society .

Savolainen. (2004). A detailed picture of the origin of the Australian dingo, obtained from the study of mitochondrial DNA. Proceedings of the National Academy of Sciences .

Shannon. (2015). Genetic structure in village dogs reveals a Central Asian domestication origin. Proceedings of the National Academy of Sciences .

Vila. (1997). Multiple and Ancient Origins of the Domestic Dog. Science .

vonHoldt, (. (2010). Genome-wide SNP and haplotype analyses reveal a rich history underlying dog domestication. Nature .

 



[1] http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=726820

[2]http://vertebrates.si.edu/msw/mswcfapp/msw/taxon_browser.cfm?msw_id=11387&CFID=5084850&CFTOKEN=14410530&jsessionid=7e30a142117d66d6620c6f747113647cb1b2

[3]http://www.mammalsociety.org/uploads/LIST%20OF%20IMAGES%20IN%20MAMMAL%20IMAGES%20LIBRARY%2001-31-2016.pdf

[4] http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/afd/taxa/Canis_familiaris

[5] Wayne. 2010. Genome-wide SNP and haplotype analyses reveal a rich history underlying dog domestication

[6] Savolainen. 2004. A detailed picture of the origin of the Australian dingo, obtained from the study of mitochondrial DNA

[7] Oskarsson. 2011. Mitochondrial DNA data indicate an introduction through Mainland Southeast Asia for Australian dingoes and Polynesian domestic dogs

[8] Dwyer. 2015. Wild dogs and village dogs in New Guinea: Were they different?

[9] Ardalan. 2012. Narrow genetic basis for the Australian dingo confirmed through analysis of paternal ancestry.

[10] Vila. 1997. Multiple and Ancient Origins of the Domestic Dog

[11] Freedman. 2012. Genome Sequencing Highlights the Dynamic Early History of Dogs

[12] Larson. 2012. Rethinking dog domestication by integrating genetics, archeology, and biogeography

[13] Brown. 2011. Phylogenetic Distinctiveness of Middle Eastern and Southeast Asian Village Dog Y Chromosomes Illuminates Dog Origins

[14] Shannon. 2015. Genetic structure in village dogs reveals a Central Asian domestication origin

[15] Balme. 2015. Dingoes and Aboriginal social organization in Holocene Australia