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In the desolate desert 150 kilometers southwest of Cairo there is a fearsome arid valley (wadi) of cliffs, carved buttes, and sandblasted erratic boulders. The bleached landscape has an otherworldly emptiness as though it were located on a lifeless alien planet, though if you look closely, the desert is filled with austere furtive life like dorcas gazelles, tiny sand colored lizards, cobras, scorpions, and fennec foxes. The name of the place is even more otherworldly—“Wadi Al-Hitan” which is Arabic for “valley of the whales” and although the great smooth rocks buckling out of the sand might momentarily be taken for the backs of huge whales, the utter absence of the ocean (or of water of any kind) makes the name seem fanciful. The nearby Mount Garet Gohannam (which means mountain of hell because of the way it glows like flames at sunset) seems to be more aptly named.
However the name of Wadi Al-Hitan is remarkably literal–for the valley contains the remains of hundreds of huge ancient cetaceans which died in the Eocene and were fossilized in the yellowish sandstone. Forty million years ago the valley was a marine lagoon. Although the remains of numerous sirenians, sawfish, sharks, rays, sea turtles, marine crocodiles, sea snakes, and even swamp dwelling moeritheriums have been discovered in the wadi, the valley takes its name from the most spectacular and numerous fossils which belong to four different species of primitive whales. The most commonly discovered fossils belong to Dorudon, which was 3-5 meters long (9-15 feet) and fed on fish and mollusks, and to Basilosaurus, which was 15-22 meter (50-72 foot) and fed on everything else in the ocean.
Basilosaurus was first discovered in Louisiana in the early 19th century. Its immense size and serpentine form initially convinced naturalists that it was a marine reptile and they misnamed the creature Basilosaurus (which means “king lizard”). The mistake soon became obvious and Basilosaurus was classified among the Archaeoceti, a paraphyletic suborder of the cetaceans, however the giant kept its dinosaur name. Different species of Basilosaurus flourished in oceans worldwide during the wet, tropical Eocene and, even though they were obviously very adept at ocean living (indeed rising to the top of the food chain) the creatures betray vestiges of terrestrial living which modern whales have entirely dispensed with. Not only do Basilosaurus fossils have teeth and jaws which retain reatures from their artiodactyl ancestors, they also have tiny vestigial back legs a mere half meter in length (which would scarely help a 22 meter animal get around). Additionally Basilosaurus was different from modern whales in that it probably moved with eel-like horizontal thrashing of its long tail (modern whales move their flukes vertically). Basilosaurus probably did not dive very deeply, but moved about near the surface of the oceans hunting for smaller marine animals.
Although Wadi Al-Hitan was discovered by Europeans in 1902-1903, some archaeologists and anthropologists have speculated that it was known long before that and have been irresistibly drawn towards comparing basilosaurus with the giant crocodiles and earth spanning serpent gods which populate ancient Egyptian cosmology.
There are twenty extant species of armadillos–new world placental mammals covered with armored plates. The smallest of these armored creatures is the Pink Fairy Armadillo (Chlamyphorus truncates) which is only 9-12 centimeters in total length (about 4 or 5 inches). The diminutive creature weighs slightly more than 100 grams when mature and inhabits the central drylands of Argentina. It has multiple hard ring-like plates of delicate pink which it can close into a box form for protection (although its first defensive strategy is to dig into the ground). The animal has tiny eyes and a torpedo-like head for pushing into the sand. The portions of the Pink Fairy Armadillo not covered with plates are covered in dense white fur. Like the golden mole of Namibia, the pink fairy armadillo is a sand swimmer: the little animal agitates the fine, dry sand with its powerful claws and literally swims through the turbulence with its hard bullet shaped body. The armadillos are also like the golden mole in that they can lower their metabolism to levels unheard of among other placental mammals. However armadillos are not closely related to the golden mole—or indeed to any other placental mammals other than fellow Xenarthra (the sloths, armadillos, and anteaters). South America spent a long portion of geological time as an island and the mammals there had a long time to develop on their own. It is still not known whether Xenarthrans like the Pink Fairy Armadillo are truly Eutherians or whether they are the descendants of the ancestors of the Eutherians (sorry: the language of cladistics does not lend itself to eloquent explanations and all of the names sound like they come from a far-away planet—for example “Xenarthrans”).
I would like to tell you more about the Pink Fairy Armadillo, but I am unable to do so. Since it lives underground, the animal is rarely seen in the wild. It is even more unusual in captivity where it does not long survive the shocks and stresses of zoo living (additionally it seems unable to live on anything other than local invertebrates). This is unfortunate as it is believed that the Pink Fairy Armadillo is struggling in the wild. It is presumed to be declining in numbers–a victim to habitat loss from human activity. I used wiggle words like “believed” and “presumed” because nobody really has any idea about the actual populations of Pink Fairy Armadillos.
In the absence of real information here is a little gallery of Pink Fairy Armadillo artwork. Enjoy these pictures, it is profoundly unlikely you will ever see a real Pink Fairy Armadillo in the real world (which is sad because I find them curiously endearing). I particularly like the cartoon of the Pink Fairy Armadillo dreaming of transcendence into a mythical fairy being.
Yesterday I spent some time describing the Namib Desert (as well as giving a brief overview of the entire nation of Namibia). I did this not just because Namibia strikes me as one of the most striking landscapes on earth, but because the harsh habitat is home to a profoundly strange mammal, Grant’s Golden Mole (Eremitalpa granti), a solitary, nocturnal predator of the Nagib Desert. Grant’s golden mole lives primarily in the Namib Desert but ranges as far north as Angola and as far south as the arid dunes of South Africa.
The golden moles are already strange animals. The name “mole” is a misnomer: golden moles are not closely related to the true moles (which are insectivores) or to the marsupial moles of Australia. Their taxonomical classification is presently unclear but they seem to be most closely related the tenrecs, a group of insect eating primitive placental mammals. Tenrecs and golden moles both have unusual dentition (a critical feature to the taxonomist) and possess cloacas like birds. It has been speculated that tenrecs and golden moles are closely related to the first placental mammals, but this may be a mistake. It is also possible that the tenrecs resemble the ancestral placental mammal of long ago whereas golden moles have evolved features which uniquely suit their desert environments.
Grant’s golden mole is a particular anomaly since it is so profoundly suited for desert living (which may have to do with the great age of the Namib Desert). Grant’s golden mole does not make permanent burrows but literally swims through the sand. The creature has powerful claws for digging which have almost some to resemble “sand flippers”. It can move swiftly underground and detect its prey (termites, scorpions, and lizards) through its profoundly acute sense of touch. Its eyes have become vestigial and are covered with both skin and fur. Because it burrows through fine particles of sand, its coat is incredibly fine and dense, its nose is a leathery wedge, and its ears have shrunk to tiny, tiny openings.
Grant’s golden mole does not build burrows so it is not known how or where it raises its young. Because water is so scarce in the Namib Desert, the golden mole does not drink: its kidneys are hyper efficient. It also does not regulate its temperature in the manner of other mammals and it is capable of dropping into a suspended state during the days (when it digs deep down into the oxygen poor sand). Grant’s golden mole requires large swaths of sandy desert for hunting. It lives only on the shifting dunes. With such a lifestyle you would think that it has escaped trouble from humankind, but you would be wrong. The giant sand mines of Namibia are eating into its habitat and it is preyed on by feral cats. In so far as we know anything about its numbers, we believe it is threatened. Even in one of the most inhospitable places, humans are making inroads.