Happy New Year!
This month’s blog
is about the beautiful Old World Monkeys
that occupy the Ethiopian Highlands,
the Geladas.
Geladas, Theropithecus gelada, are a
fascinating group of primates most
closely related to the baboons, drills
and mandrills.
Two sub-species have
been described:
-
The Northern Gelada, Theropithecus gelada gelada
-
Hueglin’s Gelada, Theropithecus gelada
obscurus.
Geladas live in large groups
in the mountains of Ethiopia. These
monkeys occupy some of the highest
altitudes of all the primates, reaching
heights of over 14,700 feet above sea
level!
Male and Female Gelada - notice the
differences in size
Photo Credit:
Ondřej
Žváček
Geladas are large bodied primates with
strong
sexual dimorphism:
males average
at 40 pounds, while females average
approximately 24 pounds.
Their fur is
coarse and dark with dark skinned faces
and pale eyelids. Adult males have
a long heavy cape of hair on their
backs.
Male Gelada
Photo Credit: Kolumbusjogger
One of the most notable physical attributes
of the Gelada is their crescent shaped
chest patch analogous to sexual
swellings in baboons and chimpanzees.
These chest patches are found on both
males and females. On males they are
bright red and surrounded by white hair.
On females they are less pronounced, however when in
estrus the female's patch becomes
brighter and
covered in blisters. This is most
likely an evolutionary adaptation as a
result of spending lots of time sitting
down to feed on grasses.
Female Gelada
Photo Credit: BluesyPete
Geladas are primarily
graminivores, feeding
on grasses. After humans, the Gelada is
known to have the most advanced
opposable thumb in the animal kingdom,
which is advantageous for their eating
habits.
Gelada Eating Grasses
Photo
Credit: Hulivili
Although their conservation status is
categorized as Least Concern by
the
IUCN, their
population has dropped from an estimated
440,000 in the 1970’s to 200,000 in
2008. Major threats to the gelada are
human encroachment on their range
resulting from agricultural expansion,
and being shot as crop pests. Previous
threats that no longer exist are
trapping for use as laboratory animals
and shooting to obtain their capes to
make clothing. As of 2008 there were
proposals for a new Blue Nile Gorges
National Park and Indeltu (Shebelle)
Gorges Reserve that would protect their
numbers.
This species is not only stunning, highly
adaptive and social, but also one of my
favorite primates!
What does that mean?
Gramnivore
- Herbivorous animal that feeds on
grasses. Latin roots of the word
include graminis ‘grass’ and vorare
‘to eat.’
Sexual
dimorphism
- The differences in appearance
between males and females of the
same species.
IUCN -
International Union for Conservation
of Nature
What you can do?
