Evidence for two independent domestications of cattle.

Abstract

The oIIn and taxonomic status of domesticated cattle are controversial. Zebu and taurine breeds are differentiated primarily by the presence or absence of a hump and have been recognized as separate species (Bos ndicus and Bos taurus). However, the most widely held view is that both types of cattle derive from a single domestication event 8000-10,000 years ago. We have examined mtDNA sequences from representatives of six European (taurine) breeds, three Indian (zebu) breeds, and four African (three zebu, one taurine) breeds. Simila levels of average sequence divergence were observed among animals within each of the major continental groups: 0.41% (European), 0.38% (African), and 0.42% (Indian). However, the sequences fell into two very distinct geographic lineages that do not correspond with the taurinezebu dichotomy: all European and African breeds are in one lineage, and all Indian breeds are in the other. There was little indication ofbreed clustering within either lineage. Application of a molecular dock suggests that the two major mtDNA clades diverged at least 200,000, and possibly as much as 1 million, years ago. This relatively large divergence is interpreted most simply as evidence for two separate domestication events, presumably of different subspeces of the aurochs, Bos prmigenius. The clustering of all African zebu mtDNA sequences within the taurine lineage is attributed to ancestral crossbreeding with the earlier B. taurus inhabitants of the continent.Cattle have had a central role in the evolution of human cultures and are the most economically important of domesticated animal species (1). There are two major types, zebu (humped) and taurine (without humps), which are named as separate species (Bos indicus and Bos taurus), but which, due to complete interfertility, are more often considered as subspecies. Of the 800 breeds thought to exist, many are under threat of extinction, principally as a result of modem agricultural practices (2). An understanding of the extent and pattern of genetic variability among breeds may help in the development of more rational breeding programs (3) and is a prerequisite to the informed conservation of genetic resources (3, 4). Furthermore, determination of the genetic relationships among cattle breeds should complement and clarify archeological data on the origins of animal husbandry. Elucidation of the events surrounding bovine prehistory has proved quite difficult, since the distinction between wild and domesticated forms of a species is not always clear from the archeological record. In addition, data from sources such as rock paintings are often patchy and notoriously hard to date. These artifacts generally do not yield satisfactory information on the types or breeds of early domesticated cattle.To address some of these issues, we have examined mtDNA from representative breeds (listed in Table 1) of European, African, and Indian cattle. Sequences of =900 bp comprising the entire displacement loop (D loop), the most variable mtDNA region (5), were determi...

An Exploration of Diversity Among the Ostertagiinae (Nematoda: Trichostrongyloidea) in Ungulates from Sub-Saharan Africa with a Proposal for a New Genus

“…In Africa, structure of the fauna was likely to have been influenced by the differential timing of expansion events from Eurasia and periods of occupation for respective pecoran groups, including Antelopinae, Bovinae, Hippotraginae, Reduncinae, and others since the Miocene, in parallel to radiation among species of Haemonchus (Vrba 1985(Vrba , 1995Vrba and Schaller, 2000;Hoberg et al, 2004). Subsequently, domestication and later translocations during the Holocene for cattle and sheep (Ryder, 1984;Loftus et al, 1994) influenced distribution and diversity for trichostrongylid faunas (e.g., Daubney, 1933). Mosaic faunas among ungulate nematodes have now been demonstrated for all biogeographic regions (e.g., Hoberg et al, 1999Hoberg et al, , 2001Hoberg et al, , 2004Hoberg, 2005).…”

Multiple paternal origins of domestic cattle revealed by Y-specific interspersed multilocus microsatellites

“…Cattle history, inferred from mitochondrial DNA (mtDNA) markers (Bradley et al, 1996;Loftus et al, 1994Loftus et al, , 1999Troy et al, 2001;Edwards et al, 2007a;Achilli et al, 2008), suggests that cattle (Bos taurus and Bos indicus) domestication involved at least two genetically distinct auroch (Bos primigenius) species in the Near East and great Indus Valley. Most European cattle resulted from the expansion of a small cattle population from the Near East after domestication, with one (T3) of the four major haplogroups (T, T1, T2 and T3) identified in the Near East predominating in the mainland continent.…”

Hybridization of banteng (Bos javanicus) and zebu (Bos indicus) revealed by mitochondrial DNA, satellite DNA, AFLP and microsatellites

“…Several DNA markers are now available to analyse the genetic background of hybrid Bovini. Mitochondrial DNA (mtDNA) markers reveal introgression via the maternal lineage (Loftus et al, 1994a;Ward et al, 1999;Verkaar et al, 2003). The species origin of the nuclear genome can be inferred from species-specific microsatellite alleles (Frisch et al, 1997;MacHugh et al, 1997), AFLP patterns (Vos et al, 1995;Savelkoul et al, 1999;Buntjer et al, 2002) or mutations in satellite DNA.…”