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This family includes only two living species, the giraffe and the okapi. These two very different animals are restricted to subSaharan Africa.
Giraffids are large (okapis) to huge (giraffes); weights range from around 250 kg to over 1500 kg. They have long and narrow heads, thin lips, and long, seemingly prehensile tongues. Okapis lack, however, the extraordinary long neck and legs of giraffes. Both species have long, narrow, fully
unguligrade
feet that lack lateral digits. Third and fourth
metapodials
fuse to form
cannon bones
. The
tarsals
of giraffes consist of only four bones:
calcaneum
,
astragulus
, fused navicular and cuboid, fused cuneiforms. Okapi tarsals are even more specialized, consisting of just three bones.
Giraffids have short
horns
that project from the 
parietals
and
frontals
. These are unique among mammals, consisting of bony cores (
ossicones
) covered by furred skin.
In addition to having unusual horns, giraffid skulls lack
sagittal crests
, and they may have rough, thickened areas near the junction of the
nasals
and frontals which in some populations develops into a third horn. A
postorbital bar
is present. The
mandibles
are very long and slender. The skull of the giraffe contains extensive pneumatized areas and is remarkably light for its size. These pneumatized areas are much less well developed in the okapi.
The cheekteeth of giraffids are
selenodont
and
brachydont
. Upper
incisors
and
canines
are absent. The lower
incisors
and incisor-like
canines
are separated from the
cheek teeth
by a very long
diastema
. The
dental formula
is 0/3, 0/1, 3/3, 3/3 = 32.
Giraffids have a complex four-chambered, ruminating stomach.
Okapis and giraffes are very different in their ecology and behavior. Okapis inhabit the deep forests of central Africa. They are solitary animals with relatively small home ranges. Their diet includes mostly browse, but they also graze on grasses. Giraffes are gregarious, living in herds of up to 25 animals, which occupy large home ranges usually in relatively open savannahs. Their eyesight is excellent (in contrast to that of okapis). They are exclusively browsers, using their long necks to reach into the crowns of trees to feed.
Giraffids first appeared in the fossil record in the early Miocene.
Technical characters
:
References and literature cited:
Feldhamer, G. A., L. C. Drickamer, S. H. Vessey, and J. F. Merritt. 1999. Mammalogy. Adaptation, Diversity, and Ecology. WCB McGraw-Hill, Boston. xii+563pp.
Nowak, R.M. and J.L. Paradiso. 1983. Walker's Mammals of the World, 4th edition . John Hopkins University Press, Baltimore, MD.
Savage, R. J. G. and M. R. Long. 1986. Mammal Evolution: An Illustrated Guide. Facts on File Publications, UK. 251 pp.
Simpson, C. D. 1984. Artiodactyls. Pp. 563-587 in Anderson, S. and J. K. Jones, Jr. (eds). Orders and Families of Recent Mammals of the World. John Wiley and Sons, N.Y. xii+686 pp.
Vaughan, T. A. 1986. Mammalogy. Third Edition. Saunders College Publishing, N.Y. vii+576 pp.
Vaughan, T. A., J. M. Ryan, N. J. Czaplewski. 2000. Mammalogy. Fourth Edition. Saunders College Publishing, Philadelphia. vii+565pp.
Wilson, D. E., and D. M. Reeder. 1993. Mammal Species of the World, A Taxonomic and Geographic Reference. 2nd edition. Smithsonian Institution Press, Washington. xviii+1206 pp.&160;
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