What do we really know about free living groups of dogs? Published work by the Swiss animal behaviourist, Rudolph Schenkel, of his wolf studies in the 1930s and 1940s gave rise to the idea of pack leaders and this idea is still referred to all too often today. His work was based on captive wolves in a zoo and has since been recognized, including by Schenkel, as not giving a picture of free-living wolves or dogs. More recently claims have been made that a “pack” consists of the mother and her pups and that only the “alpha female and alpha male breed”. This is then also picked up and claimed to be the same with free living dogs. Free living dogs do not have rules they follow and there has not been any long-term study of many dog groups, individuals or their movements done over several generations to give a clear picture and it is unlikely that one size fits all. From genetic studies we do know, however, that in general freeborn dogs have a lower coefficient of inbreeding (COI) than do human controlled breeds suggesting movement between groups is common. There is of course an occasional exception when a parent and sibling or 2 siblings have mated but his seems to be rare and may be a result of movements having been restricted when dogs find themselves caught in a built-up city area.
One of the dogs in the group initially tested, Aswad, was later shown by Embark to have a close relative, Ramy. On checking it was confirmed that they had both came into the same shelter together and that the size difference suggested they might be a father and son. From the genetics they share 28% similarity, so it seems they were half siblings from separate litters, with their haplotypes suggesting they probably had the same father but different mothers.
Genetic results of other dogs living in a group or close by groups show interesting connections as follows. Of the dogs tested none of the dogs in the same group as Pack leader, so named because of the role the people feeding these dogs observed him to be, showed as his pups. He was related to Figa, Hannah and Finn at a level of half siblings, aunts/uncles or grandparents, and to Jimmy and Jenny as first cousins and yet Hannah and Figa were living together in a separate area to Pack leader. Hannah and Figa shared their genetics (40%) at a level where they were probably half siblings or possibly aunts/uncles or grandparents. They have the same maternal haplotype so likely had the same mother. Hannah and Finn could also be half siblings of Pack leader but did not have the same mother as Pack leader since Pack leaders maternal haplotype was different. Jimmy and Jenny could be as related to Pack leader as first cousins and share 43% of their genetic makeup and have the same maternal haplotype that none of the other dogs had, so probably had the same mother. They were in a separate group.
Most closely related were Jenny and Jimmy at 43% and with the same mother as they both have the same maternal haplotype. Hannah and Figa at 40% and again with shared maternal haplotype so same mother but different to Jenny and Jimmy. Dasha and Dave with 31% and again the same mother as they have the same maternal haplotypes but different to the other siblings. Lara and Luna at 22% and again share the same maternal haplotypes so had the same mother that none of the others had. Figures shown are the percentage of DNA shared between connected dogs.
Hannah and Figa share 40% of their genes so are probably half siblings and share the same maternal haplotype A437 so probably the same mother.
Jenny and Jimmy share 43% of their genetic make up so are probably full siblings and share the same maternal haplotype C34 so probably the same mother. They were from a different group to Hannah Figa and Pack leader.
Lara and Luna share 22% of their genes as well as the same maternal haplotype so probably have the same mother but different fathers and were not family relatives of other dogs tested.
Savvy and Sandy from Dhahran were thought to be siblings or half siblings but only share 17% DNA, a level equivalent to first cousins. They do share the same maternal haplotype suggesting their mothers may have been siblings.
Complicating this in dogs is that in one litter it is possible that more than one male dog may have mated. On average, siblings who share the same parents are approximately 50% genetically related. But if more than one male fathers a litter, the half-siblings puppies are only ~25% genetically similar. This is known as superfecundation and while extremely rare in humans it can occur in twins.
