Ecology, Conservation and Management of Wild Pigs and Peccaries

(Axel Boer) #1
Part I: Evolution, Taxonomy, and Domestication

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perhaps three, species of collared peccaries (Gongora et al. 2006;
Groves & Grubb 2011).
Suoidea likely emerged in the Middle–Late Eocene of China
and Thailand (Tong & Zao 1986; Ducrocq et al. 1998; Liu 2001)
and subsequently diversified into various families including
extant Suidae and Tayassuidae represented by a number of
primitive forms (Pickford 1993; Wright 1993a, 1993b, 1998;
Orliac et al. 2010a). Although a great deal of our understanding
of suoid evolutionary history is based on dental morphology,
taxonomic difficulties persist in differentiating early Suidae and
Tayassuidae, so that some of their evolutionary relationships
remain unresolved (Liu 2001, 2003; Harris & Liu 2007; Prothero
2009; Orliac et  al. 2010a; van der Made 2010; Pickford 2012).
For instance, morphological studies show that extinct Old
World Tayassuidae form a distinct clade whereas New World
Tayassuidae appear to be paraphyletic, showing an unresolved
relationship with other primitive suoids from the Old World
(Orliac et al. 2010a). This has given rise to the hypothesis that
there were at least two events of colonization by tayassuids
from Asia into the Americas (Frantz et al. 2016), although this
ambiguity could be the result of limited sampling and/or dif-
ferent cranial characters used in relation to previous studies by
Wright (1993a, 1993b, 1998) (D. Prothero, personal communi-
cation). This debate has not been an impediment to estimating
that Suidae and Tayassuidae diverged from a common ances-
tor sometime during the Late Eocene (37–34 Ma) in South East
Asia, based on both morphological and DNA data (Ducrocq
1995; Randi et al. 1996; Ducrocq et al. 1998; Wright 1998; Orliac
et al. 2010a; Gongora et al. 2011a), and that they subsequently
dispersed into the Old World with Tayassuidae also migrating

into the New World as early as the Late Eocene as attested by the
presence there of the genus Perchoerus (Ducrocq 1995; Wright
1998; Harris & Liu 2007; Prothero 2009).

Suidae


Diversification and Dispersal
The earliest known fossil suid, Hyotherium, occurred in Early
Oligocene deposits on the Indian subcontinent (Orliac et  al.
2010a, 2010b). Throughout the Neogene, Suidae diversified into
approximately 20 genera, representing up to seven subfamilies,
including Suinae, which may have originated towards the end of
the Middle Miocene (11–10 Ma) (Pickford 1993; Harris & Liu
2007; Orliac et al. 2010a). Many genera of Suinae had emerged
by the beginning of the Pliocene including Porcula and Sus
(Hodgson 1847; Pilgrim 1926; Thenius 1970; Liu 2003; van der
Made et al. 2006). By many authors, all of the extant suid spe-
cies are classed as representatives of Suinae (Grubb 2005; Harris
& Liu 2007), with some debate in relation to Babyrousa as dis-
cussed below.
Fossil biochronologies indicate that six subfamilies of
Suidae, including Suinae, colonized Africa from Eurasia at least
six times during the Plio-Pleistocene (Pickford 2006). Suinae
dispersed into Africa from the Middle Miocene and became
the predominant and only subfamily among Suidae in this con-
tinent (Cooke 1978; Cooke & Wilkinson 1978; Harris 1983;
Bender 1992; White 1995; Kullmer 1999; Geraads 2004; Pickford
2006). The first fossil evidence of the African Suinae is the
genus Kolpochoerus, around the Miocene–Pliocene boundary

Figure 1.1 World map showing the natural distribution of extant Suidae in Africa, Asia, and Europe and Tayassuidae in the Americas. This is based on data
extracted from various sources including the IUCN Red List of Threatened Species homepage (www.iucnredlist.org/). Designed by Daniele Baisero of the Global
Mammals Assessment, University ‘La Sapienza’, Rome (Source: IUCN).

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