The Caninae, known as canines, are one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct

Borophaginae The extinct Borophaginae form one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Hesperocyoninae and extant Caninae. Borophaginae, called "bone-crushing dogs", were endemic to North America dur ...

and

Hesperocyoninae The extinct Hesperocyoninae are one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Borophaginae and extant Caninae. Taxonomic history Hesperocyoninae are basal canids that gave rise to the o ...

. The Caninae includes all living canids and their most recent fossil relatives. Their fossils were first found in North America and dated to the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but t ...

era, then spreading to Asia at the end of the

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

era, some 7 million to 8 million years ago.

Taxonomy and lineage

The genus ''

Leptocyon The genus ''Leptocyon'' (Greek: ''leptos'' slender + ''cyon'' dog) includes 11 species and was the first canine Canine may refer to: Zoology and anatomy * a dog-like Canid animal in the subfamily Caninae ** ''Canis'', a genus including dogs, w ...

'' (Greek: ''leptos'' slender + ''cyon'' dog) includes 11 species and was the first primitive canine. They were small and weighed around 2 kg. They first appeared in Sioux County, Nebraska in the Orellan era 34-32 million years ago, which was the beginning of the

. This was the same time as the appearance of the Borophaginae with whom they share features, indicating that these were two sister groups. Borophaginae skull and dentition were designed for a powerful killing bite compared with the ''Leptocyon'' which were designed for snatching small, fast-moving prey. The species ''L. delicatus'' is the smallest canid to have existed. At the close of their genus 9 million years ago one ''Leptocyon'' lineage resembled the modern fox. The various species of ''Leptocyon'' branched 11.9 Mya into Vulpini (foxes) and Canini (canines). The canines spent two-thirds of their history in North America, before dispersing 7 million years ago into Asia, Europe, and Africa. One of the characteristics that distinguished them from the Borophaginae and Hesperocyoninae was their possession of less weight in their limbs and more length in their legs, which may have aided their dispersion. The first canine to arrive in Eurasia was the coyote-sized ''Canis cipio'', whose scant fossils were found in Spain. However, the assignment of ''C. cipio'' within the canines to the genus ''

Canis ''Canis'' is a genus of the Caninae which includes multiple extant species, such as wolves, dogs, coyotes, and golden jackals. Species of this genus are distinguished by their moderate to large size, their massive, well-developed skulls and de ...

'' or genus ''

Eucyon ''Eucyon'' (Greek: : good, true; : dog) is an extinct genus of medium omnivorous coyote-like canid that first appeared in the Western United States during the late Middle Miocene 10 million years ago. It was the size of a jackal and weighe ...

'' is not clear.

Phylogenetic relationships

MSU V2P1a - Vulpes, Nyctereutes, Cuon & Canis skulls

The results of

allozyme Alloenzymes (or also called allozymes) are variant forms of an enzyme which differ structurally but not functionally from other allozymes coded for by different alleles at the same locus. These are opposed to isozymes, which are enzymes that pe ...

and

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins ar ...

analyses have previously suggested several

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups ...

divisions: DNA analysis shows that the first three form

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gr ...

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...

s. The wolf-like canines and the South American canines together form the tribe Canini. Molecular data imply a North American origin of living Canidae some 10 Mya and an African origin of wolf-like canines (''Canis'', ''Cuon'', and ''Lycaon''), with the jackals being the most basal of this group. The South American clade is rooted by the maned wolf and bush dog, and the fox-like canines by the fennec fox and Blanford's fox. The gray fox and island fox are basal to the other clades; however, this topological difference is not strongly supported. The cladogram below is based on the phylogeny of Lindblad-Toh (2005) modified to incorporate recent findings on ''Canis'', ''Vulpes'', ''

Lycalopex The South American foxes (''Lycalopex''), commonly called ''raposa'' in Portuguese, or ''zorro'' in Spanish, are a genus from South America of the subfamily Caninae. Despite their name, they are not true foxes, but are a unique canid genus mo ...

'' species, and ''

Dusicyon ''Dusicyon'' is an extinct genus of South American canids. The type species is ''Dusicyon australis'', the Falkland Islands wolf. In 1914, Oldfield Thomas established this genus, in which he included the culpeo and other South American foxe ...

''.

References

External links

{{Taxonbar, from=Q2474088 Extant Miocene first appearances