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Chapter

4

A History of Pig Domestication: New Ways

of Exploring a Complex Process

Allowen Evin, Keith Dobney, and Thomas Cucchi

The domestic pig is among the first animal to have been domes-
ticated. Its domestication dates from the beginning of the
Holocene – when so-called Neolithic cultures across the Old
World began to farm and a period that saw the domestication
of the principal farmyard animals (i.e. sheep, goat and cattle).
Domestic pigs have a peculiar place among domestic animals.
First, its wild ancestor, the wild boar (Sus scrofa), possesses a
very large natural range from Island South East Asia (where
genetic evidence shows it first originated) to western Europe –
contrary to the wild ancestors of sheep and goat that live in a
very restricted area. Second, wild boar still exist in abundance
in the wild – unlike, for example, the wild ancestor of cattle (the
aurochs), the last of which was killed in Poland in 1627. Today,
the history of pig domestication is certainly one of the most
studied of all domestic animals. They are without doubt one
of the most important global food sources – their meat being
the most consumed of all terrestrial animals (www.fao.org/ag/
againfo/themes/en/pigs/home.html, accessed 9 March 2016).
Evidence from the archaeozoological record shows the pres-
ence of at least two independent pig domestication centres: one
in western Asia, at the eastern fringe of Anatolia dated around
8500 BC ( Ervynck et al. 2001; Conolly et al. 2011); the second
in China, along the Yellow River valley around 6500 BC (Jing &
Flad 2002; Cucchi et al. 2011b). More recent genetic studies of
modern wild and domestic populations suggested several addi-
tional geographical regions where pig domestication could have
also occurred (Larson et al. 2005). This study, based on analysis of
a neutral genetic marker, mitochondrial DNA (mtDNA, which
is maternally inherited), found a strong phylogeographic signal
for both wild and domestic Sus initially suggesting several wild
boar populations must have contributed to the genetic make-up
of modern domestic pig stocks. Surprisingly, it appeared that all
modern European and Near Eastern domestic pigs possessed
a genetic signature similar to those of modern European wild
boar, and not similar to those found in Near Eastern wild boar
where the archaeological evidence suggested early pig domes-
tication had occurred. These data in fact appeared to indicate
a European and not a Near Eastern domestication scenario.
Subsequent analysis of ancient Sus scrofa DNA reconciled the
modern DNA and archaeozoological evidence by showing that
sometime between the sixth and the fourth millennium BC,
domestic pigs carrying a Near Eastern mitochondrial signa-
ture were in fact introduced into Europe by Neolithic farmers
(Larson et al. 2007a). This Near Eastern genetic lineage, how-
ever, did not persist over time, and by the fourth millennium

BC, all European archaeological specimens analysed possessed

a local European genetic signature. This result can be explained

either by admixture between the local wild boar and the intro-

duced domestic Near Eastern pigs (a cross between a female

European wild boar and a male domestic pig will result in only

a European mitochondrial signature present in the offspring),

or a local domestication of European wild boar (genetically

independent but not necessarily culturally independent from

the Neolithic introduction of the domestic pigs of Near Eastern

origin). Thereafter, during the Bronze Age, European domestic

pigs were present in Asia Minor, and by the fifth century AD the

European genetic signature appears to have completely replaced

the local south-western Asian lineages – possibly the result of

human migration or trade and exchange during the Anatolian

Bronze and Iron Ages (Ottoni et al. 2013).

In East Asia it seems that multiple modern wild boar pop-

ulations were involved in domestication (Larson et al. 2005)

with the archaeological evidence pointing principally to

China (Cucchi et  al. 2011b). Interestingly, the natural range

of Sus scrofa does not include any islands east of the Wallace

Line, and the presence of extant pigs (and their bones and

teeth recovered from ancient archaeological sites) in this area

has clearly resulted from human introduction (Groves 1983).

Ancient DNA analyses (Larson et al. 2007b) appeared to show

two separate past human-mediated dispersals of domestic pigs

through Island South East Asia (ISEA) and Oceania: a first

likely associated with the Neolithic Austronesian migrations

that left a unique mtDNA signature (called the ‘Pacific clade’)

from South East Asia, along the lesser Sunda islands in ISEA

and throughout remote Oceania, suggesting that this dis-

tinctive lineage may have a peninsular South East Asian wild

boar origin. A second (and later) dispersal links specimens

from East Asia, the Philippines, Taiwan, and the Micronesian

islands of Guam and Rota. A third human-mediated pig dis-

persal, likely earlier than the two previously described, was

also identified for another endemic Sus species from ISEA (Sus

celebensis; see Chapter 19) and involved human translocation

of specimens from Sulawesi to the island of Flores (Larson

et al. 2007b).

Domestication is a complex evolutionary process, during

which animals and plants are moved from the natural envi-

ronment to a new one controlled by man. Over the millennia,

domestication has also led to profound morphological changes

to achieve the variety of observable modern pig breeds and

their differentiation from wild boar. Although genetic studies

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