The giraffe and its cousin the okapai have a long history on our planet
Earth. Fossils of the Giraffidae family go all the way back to the Oligocene
(38-26 million years ago). In times past they ranged over a wider territory than
they do today. Giraffe fossils have been found in China that date to the Miocene
period (27-7 million years ago). Jie Ye mentions them in an article titled
Middle Miocene Artiodactyla from the Northern Junggar Basin. This article was
published in Vertebrata PalAsiatica. It is Volume 27, No. 1 of January, 1998.
The essay was translated by Will Downs of the Bilby Research Center of Northern
Arizona University in October of 1999.
In the Abstract of the article, Jie Ye says:

The text describes seven genera, seven species of artiodactyls (including
Eotragus halamagaiensis sp. nov.), in addition to recording three genera and
three species of perissodactyls from the Halamagai Formation, northern Junggar
Basin, Xingiang Autonomous region. This fauna contains elements that approach
the Tonggar fauna from eastern Inner Mongolia, although several more taxa are
more primitive.

In the Forward, Jie Ye states:

The Xingiang Paleontological Expedition mounted by the Institute of
Vertebrate Paleontology and Paleoanthropology was conducted twice in 1982 and
1984 to study Teriary sediments along the banks of the Ulungur He River where
abundant fossil vertebrates are produced from the Halamagai Fm.

Jie Ye goes on to say that most of the specimens are artiodactyls and that
they are the most diverse in terms of taxonomy. There are 5 families, 7 genera,
and 7 species of the order in the fossils found there.
In another section of the article Jie Ye discusses details concerning the
giraffe fossil specimen:

Giraffidae Gray, 1821
Palaeomeryx sp.


Material: A single left m2 (V8594.1) and a single left m1 (V8594.2)
[Note - m2 and m1 refer to molars.]

Locality and stratigraphic position: Buotomoyin, Middle Miocene lower member
of the Halamagai Fm.

Description and discussion: The m2 has a length of 22 mm and width of 18.5
mm, is brachydont, and has highly crenulated walls. The lingual wall undulates,
the paralophid conspicuously overlaps the metalophid, two ribs, a mesostylid,
and Palaeomeryx fold are well developed, the anterior wing of the protocone is
slightly thickened anteriolabially with its apex slightly anteriorly directed,
and a basal pillar is present. The m1 is small, has a length of 22 mm and
breadth of 17.2 mm, is more heavily worn than the m2, but is morphologically
similar.
In 1985, Qiu described more complete data of Palaeomeryxtricornis from
Shanwang, Shandong Province, and conducted a systematic discussion of the
diagnostic characters and their implications toward giraffid phylogeny. Three
apomorphies unite this genus with the long necked giraffids which make it the
most primitive member of the lineage and isolates it from the main stem of the
Ruminami. Its size also indicates the Shanwang fauna to correlate to MN4 or MN5.
Shanwang specimens also indicate that the male Palaeomeryx possesses
ossiones, which is a significant synapomorphy for the Giraffidae. The Xinjiang
specimens share fundamental morphological characters with the Shanwang
specimens, although they are distinctively larger, slightly more brachydont,
lingual walls are relatively more conversely rounded, and their basal pillar is
a projected inflation off the cingulum. The size of the Xinjiang specimen
approaches specimens from Sansan (MN6).

I will discuss some more aspects of giraffe paleontology in future postings.

Neal Robbins

P.S. These are definitions of terms used in the articles:

brachydont - This refers to teeth having short roots and crowns.

cingulum - ridge around the base of a tooth

mesostylid - pertains to the mesostyle, which is one of the stylar cusps along
the buccal margin of an upper molar. The mesostyle is in the middle.

protocone - mesiolingual cusp of an upper molar tooth.

metalophid - a cutting edge that generally runs along the distal side of the
trigonid on a lower lophodont molar.
[Note - Lophodont (also called selenodont) refers to dentition characterized by
lophs. A loph is a ridge of enamel in a dentine surface.]

mesiolingual - This relates to the mesial and lingual surfaces of a tooth. It
especially denotes the angle formed by the junction of these surfaces. The
mesial is the forward or front. The lingual surface is the tooth surface next to
the tongue.







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