Part I: Evolution, Taxonomy, and Domestication12
or S. ahoenobarbus. Pelage black, generally with a pale snout
band and red patches in the long mane. Young males have a ‘tou-
pee’. The inferior surface of the male’s lower canine is broader
than any other species, the index of the inferior to the poste-
rior surface being 142.1–177.8. Luzon, Mindanao and offshore
islands. Those from Mindanao are larger on average than those
from Luzon. Pigs from Jolo and Tawitawi, in far southwestern
Philippines, seem different from those from elsewhere, and
probably represent one or two further distinct species.
Sus oliveri Groves 1997. Mindoro wild pig. Resembles
S. philippensis, for example in its black colour, but falling well
outside the variation of the latter, with very long palate, wide
across zygomatic arches, broad cheekteeth and large third pre-
molars. Skull length 334–351 mm in male. Mindoro.
Groves (1981) argued that the easiest way to explain the odd,
scattered distribution of S. celebensis is that it was domesticated
prior to the introduction to Indonesia of domestic scrofic pigs,
which later largely replaced it. The pigs of New Guinea, which are
essentially a continuum of domestic and wild, have characters
intermediate between those of S. vittatus and S. celebensis; thus, it
has scrofic canines, but intact males (i.e. not castrated) have small
facial warts. As their mtDNA is like that of S. vittatus (Larson
et al. 2007a), presumably the hybridization was asymmetrical,
the paternal component being the Sulawesi warty pig. Cucchi
et al. (2009) studied the morphology of the posterior mandibular
molar of South East Asian pigs, finding it distinctive in differ-
ent OTUs (S. celebensis and S. philippensis form a group separate
from S. verrucosus, S. barbatus, S. vittatus and S. taevanus); their
sample of pigs from New Guinea formed a group apart from any
other while to an extent intermediate. This may be taken as pos-
sible support for the original hybrid hypotheses, or it may imply
that the mixture was more complex. An interesting addendum is
that the third lower molars of presumed domestic pigs from a site
in Sarawak, Lobang Kudih, dating from the thirteenth to the fif-
teenth century AD, are metrically most like those of New Guinea
pigs, suggesting much movement of domestic stock across the
islands in historic times (Cucchi et al. 2009).
Some wild boar (scrofic) populations were used by humans
for domestication. A Middle Eastern centre of domesticationhas long been recognized, and zooarchaeological records now
demonstrate clearly that pigs were also domesticated indepen-
dently in China ~8000–8300 years ago (Hongo & Meadow 1998;
Ervynck et al. 2001; Yuan & Flad 2002; Flad et al. 2007; Cucchi
et al. 2011). Larson et al. (2005) revealed that wild boar retain
a strong phylogeographic signal, and there are clear mtDNA
affinities between some of these populations and their domestic
counterparts across Europe, Asia, India and peninsular South
East Asia (Larson et al. 2005). The authors interpreted this as
multiple and independent domestication events of wild boar,
despite the absence of zooarchaeological records in some of these
regions. These views have recently been revisited, reinterpreting
the mtDNA affinities between wild and domestic populations
as more likely to be the result of admixture and introgression
after the original domestication episode took place (Larson et al.
2007b; Larson & Burger 2013); it has now been recommended
that the word ‘domestication’ should be referred to the original
episode in which the wild animals underwent a process of early
domestication, while subsequent admixture between intro-
duced domestic populations and local wild populations outside
of the areas where the original domestication took place should
be referred to as ‘introgressive capture’ (Larson & Fuller 2014).
Given the elevation of various wild boar subspecies to species
(Groves & Grubb 2011; Meijaard & Rawson 2015), as further
described below, it is possible to consider that wild boar from
other species may have also contributed to the genetics of those
domesticated from S. scrofa through hybridization between
wild boar species. Alternatively, it could be surmised that direct
domestication from different wild boar species occurred in
these regions. However, the absence of archaeological evidence
does not support the latter scenario.
Domestic forms of pig have run wild in many places, and
these feral populations (in Sardinia, Sudan, the Andaman
Islands, Nusatenggara and elsewhere) can be very difficult to dis-
tinguish from genuine wild pigs, although the brain size seems
to remain small, like a domestic animal, in feral populations.
Sus spreads naturally through vast territories, covering most
of Europe and Asia. Wild boar and domestic pigs have been
introduced in numerous in parts of the world (Figure 1.7), some
of which were deliberately released or escaped to establish feral
populations including in the USA, Australia and New Zealand
(Pullar 1953; Tisdell 1982; Clarke & Dzieciolowski 1991; Mayer
& Brisibin 2014). The deliberate release of these animals was an
attempt to naturalize them and provide food for explorers, seal-
ers, and whalers (Tisdell 1982; Oliver & Brisbin 1993). However,
feral pigs have become an environmental and agricultural
pest and, for instance, in Australia the estimated population is
between 13 and 23 million (Choquenot et al. 1996). The origin of
many of these feral pigs is uncertain in many locations because
they were poorly documented or not recorded when they were
introduced. Genetic studies have been useful to understand the
origins and genetic diversity of some of these feral populations
(Gongora et al. 2004; Fan et al. 2005; Lopez et al. 2014; Aravena
et al. 2015; Bianco et al. 2015). For instance, genetic studies have
shown that both European and Asian domestic pigs have con-
tributed to the origins of Australian and New Zealand feral pigs
(Gongora et al. 2004). In addition, it has revealed that some feralFigure 1.11 Visayan warty pig (Sus cebifrons), Los Angeles Zoo, USA. Photo by
Roland Wirth..00312:27:47