Origin of the domestic dog or the result of natural introgression as the dog expanded across Eurasia. In 2018, a study found a small amount of dog ancestry in 62% of Eurasian wolf specimens looked at, that hybridization had occurred across a wide number of timescales and not just recently, however in contrast there was almost no admixture detected in the North American specimens. There was introgression of the male dog into the wolf, but also one hybrid detected which was the result of a male wolf crossed with a female dog. Wolves have maintained their phenotype differences from the dog, which indicates low-frequency hybridization.
Dog type the written standard and awards are based on how closely the dog resembles the standard. Note 2. Many modern breeds of dogs still use the names of early types, although they may or may not resemble the old types. Note 3. Early attempts to categorize dogs as species of "Canis" are described by Carl Linnaeus in Systema naturae, 1758, Gmelin in 1788, Kerr in 1792. Dog type Dog types are broad categories of dogs based on form, function or style of work, lineage, or appearance. In contrast, modern "dog breeds" are particular breed standards, sharing a common set of heritable