A giraffe is a giraffe. Is it?

Until yesterday I knew that a giraffe is a long-necked mammal with brown patches of fur on white, which walked gracefully through east African savannas, delicately picking leaves off the tops of trees. Now, while idly surfing for information on giraffes online, I find that there are more species of giraffes than I could hope to see in one trip. Web sites called Giraffe Conservation Foundation and Giraffe Worlds list out the four main species of giraffes: the northern, the southern, the Masai and the Reticulated. IUCN, meanwhile counts only one species, but concedes that these four are subspecies, each deserving of individual conservation effort. When I tried to access original literature on giraffes I was stunned to find how little they have been studied.

The Masai giraffe (Giraffa camelopardalis tippelskirchi) ranges over large parts of Kenya and Tanzania, with an isolated population in Zambia. Even with the intense conservation effort that Kenya and Tanzania are known for, the population of the Masai giraffe has halved over the last decades, and now stands at about 35,000 individuals. This year it has been moved from a classification of Vulnerable to Endangered. It is such a pity that the tallest animal on earth, the 6 meter high adult Masai giraffe, is in danger of becoming extinct.

The reticulated giraffe (Giraffa camelopardalis reticulata) can be found in northern Kenya and southern Ethiopia (and probably inside Somalia as well). Most counts place their population at about 15,000. This has also been moved into the class of endangered species.

Distribution of giraffe species

The northern giraffe (Giraffa camelopardalis camelopardalis) has extremely fragmented habitat, and therefore has been reclassified this year as Critically Endangered. The northern giraffe contains populations called the Nubian, Kordofan and West African giraffes. The Nubian giraffe can be seen in north-western Kenya, South Sudan, and Uganda. The Kordofan giraffe can be seen in Central African Republic, Chad, and Cameroon. To see the West African giraffe you need to travel to the extreme west of Niger. This population has only about 600 individuals left. Some add the Rothschild’s giraffe, from the Baringo area of Kenya, as a separate population to this species. This can be seen in the breeding center in Nairobi.

The southern giraffe (Giraffa camelopardalis giraffa) has two sub-populations: the Angolan and South African. Fortunately, the conservation effort for this species has paid off, and both populations are on the increase. I understand that this holds out hope for giraffe conservation across the continent, although populations like the West African and Rothschild’s giraffes will have to pass through a really narrow genetic bottleneck. I understand that giraffes evolved in the Miocene era, about when apes were diverging from monkeys, and so evolved along with us in the East African Rift Valley geography which is our ur-homeland.

For a mere traveler like me, Kenya seems to be the most giraffe-diverse country. One should be able to see the Masai, reticulated, Rothschild’s, and Nubian giraffes in this one country.

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The rift where man was born

While planning a visit to the East African savanna, I thought I would read up on how old this landscape was. This led me down an exciting path of discovery through articles which connected geology, weather, and human evolution, and told me about how much more there is to see than just the Big Five. In the featured map you can see a long valley down the center of Ethiopia, ending somewhere a little south of Nairobi. Equally visible is a line of lakes along the border of Uganda and Tanzania. These are the eastern and western East African Rift Valleys.

45 million years ago, soon after India crashed into the still forming Eurasian continent, a massive plume of magma welled up from deep inside the earth near where Djibouti is today. This cracked the continential plate of Africa into three: the present day Arabian plate, and the still separating Somalian and Nubian plates. Signs of this immense geological change are visible in the creation of the Gulf of Aden, and the 30 million years old lava fields and highlands of Eritrea and Ethiopia. In geological time, this is not long before the split between monkeys and apes (hominoids). It is now believed that the geographical changes due to this initial rifting may have cause climate changes that favoured the rise of the hominoids.

The magma plume later created two bubbles below the African plate and pushed up the highlands of Kenya and Ethiopia (clearly visible in the map). About 7-10 million years ago, the heated rocks of the African continental plate began separating out, with the Nubian plate pulling west and the Somalian plate moving eastward. The land between them subsided, and the Walls of Africa rose up 3 to 4 kilometers high. The high walls blocked off wet air from the oceans, changing the climate locally, and converting forests to grasslands. This is also the time at which the split between apes and humans (hominin) took place.

Darwin thought that modern humans had arisen in the grasslands of Africa. The discovery of hominin fossils along the rift valley seemed to agree with this theory. But modern thinking is that the savanna of the rift valley and hominins evolved together as a response to geology and weather. Humans evolved in this land, and then left to settle in far corners of the world. When I go to see the annual migration in the Serengeti, or to look at the dormant volcano called Mount Kilimanjaro, or even to taste the wine grown high in Kenya’s rift valley, I will be a migrant’s child come back to marvel at the homeland that his ancestors left.