What survives out here

Stop at your first viewpoint and look down instead of up. Thin beetle tracks zigzagging across the slope. A fine double line that breaks off in the middle of nowhere, because something buried itself there. Small, almost hand shaped prints at the edge of a grass tuft. Whatever was out during the night has written it down by morning, and by late morning the wind has wiped the page clean again.

In the middle of the day the dune field looks empty. It is not. Nearly everything that lives here works at night or in the two hours after sunrise, and nearly every adaptation on this page answers the same question. Where does the water come from?

Fog is the real water supply

Some years bring no rain to the Namib at all. Moisture still arrives, not from above but from the side. The cold Benguela Current runs along the coast, warm air meets it, and out of that come the low banks of fog that drift inland overnight. The Namib coast records more than 180 foggy days a year.

How far that fog travels inland is a point the sources argue over. The classic figure for the fog zone is around 60 kilometres, while newer measurements of coastal stratus flowing over the terrain go up to 100 kilometres. Readings taken in the 1960s and 1970s put fog precipitation at stations near the coast at almost 200 millimetres a year. Around 100 kilometres inland, next to nothing was left of it.

The beetles confirm that range from a different direction. Individual fog basking beetles have been recorded up to 45 kilometres inland, which is roughly where the measurements say the fog influence gives out. The beetle stops where the fog stops.

One qualification belongs with all of this, and most travel sites leave it out. Sossusvlei and Sesriem sit considerably further inland than that zone, and one source rates the share of coastal fog there as minimal. We found no reliable figure for how often fog reaches Sesriem itself. Fog explains the Namib as a whole, its beetles, lizards and geckos, but the famous fog drinkers belong to the damper western Namib rather than to Big Daddy.

Foggy days on the coast

more than 180 a yearcold current, warm air

Reach inland

60 to 100 kmdepending on source and method

Beetle recorded up to

45 km inlandOnymacris unguicularis

Camel thorn roots

down to 60 mthrough sand to groundwater

Nara roots

up to 40 m longand up to 30 cm thick

A beetle standing on its head

The fog basking beetle (Onymacris unguicularis) is a black darkling beetle around two centimetres long, strikingly long legged and endemic to the Namib. Before sunrise it climbs to the dune crest, drops its head and tilts its rear end into the wind at roughly 20 degrees. Droplets condense on the body and run forward along the underside to the mouth. An insect wringing out a cloud.

The price is high. This beetle is otherwise active by day, and fog basking happens at temperatures 20 to 30 degrees below what suits it. It gets cold in exchange for a drink. Of more than 200 darkling beetle species in the Namib only two behave this way, both from the same genus. The other Onymacris species divide the ground between them: one on flat terrain at the dune foot, one on vegetated slopes, one near the shrubs.

The local name tok tokkie comes from a sound. Males tap their abdomen against the ground to attract females, and the tapping is said to carry for several kilometres. A multi day hiking route in the NamibRand reserve is named after it.

The lizard that dances on hot sand

The shovel snouted lizard (Meroles anchietae), also called the Namib sand diver, measures barely five centimetres from snout to vent and lives in sparsely vegetated dunes. When the surface climbs to around 70 degrees, it lifts diagonal pairs of legs in turn, front left with back right, then the other way round, roughly every ten seconds, propping itself on its tail in between. The thermal dance cools nothing, it simply shares out the time each foot spends on the hot sand.

When it gets hotter still, the lizard dives into cooler layers with that shovel of a snout and can stay down for 24 hours. Water comes from condensed fog, licked off stones and off its own skin. Popular science sources also credit it with two bladders, one for urine and one for water, holding up to 12 per cent of its body weight. We did not verify that against a primary study.

Four more specialists

• Web footed gecko (Pachydactylus rangei): nocturnal, thin legged, with broad fully webbed toes. The webbing holds fine cartilage structures that let the gecko shovel sand in a coordinated way. Its skin is almost translucent with a salmon tone, and it spends the day in a burrow it dug itself.
• Peringuey adder (Bitis peringueyi): 20 to 25 centimetres long, 32 at most. Buried just under the surface it leaves nothing showing but the eyes and the tip of the tail, and some individuals wiggle that black tail tip to draw prey closer. This snake never drinks: its prey, lizards of the genus Meroles and barking geckos, is largely made of water.
• Grant golden mole (Eremitalpa granti): swims through loose sand on broad claws rather than digging tunnels. By day it sits some 50 centimetres down where the sand is cooler and drops into torpor, by night it covers up to six kilometres hunting termites. It finds them by ear, from the way wind vibrates the roots of grass tufts.
• Dune lark (Calendulauda erythrochlamys): Namibia's one genuinely endemic bird, tied entirely to the dune system of the Namib. Among bushman grass and nara bushes it digs in the sand for invertebrates and seeds. A plain brown bird out there is usually this lark.

The oryx and its cooling system

The oryx or gemsbok (Oryx gazella) is the animal you are most likely to meet on the way to the dunes, often standing in the open plain with no shade for kilometres. Drinking water is something it can do without. It covers its needs through plants, and moisture rich food such as tsamma melons and wild cucumbers can supply up to three litres per 100 kilogrammes of body weight per day. Peak activity comes at dawn and dusk, when temperatures are bearable and predators are easier to spot.

On top of that sits an anatomy known as selective brain cooling. Like other even toed ungulates the oryx has a carotid rete, a network of vessels at the carotid artery where warm blood gives off heat to cooler blood returning from the nasal passages. Brain temperature is thereby uncoupled from body temperature. In the related Arabian oryx a threshold of 37.8 degrees was measured, with the brain running a good degree below the temperature of the carotid artery.

That mechanism almost always comes with a rider: the animal is said to let its body temperature rise to 45 degrees. The number goes back to a study from 1969. We could not check it in any primary source we could reach, so it stands here as what it is, a widely repeated figure that we have not been able to verify. The mechanism is solid, the degrees are not.

What you see out on the plain

Between the Sesriem gate and the dunes the tar road runs some 60 kilometres through open plain, patches of grass and scattered camel thorn trees. Springbok stand out here, a desert adapted antelope that copes with the driest parts of the park. Ostriches often walk in small groups parallel to the road. Black backed jackals usually trot alone, most often in the early morning, and in the Namib they have been seen licking moisture off stones.

Hartmann's mountain zebra (Equus zebra hartmannae) is not an animal of the sand. This subspecies, found almost only in Namibia, lives in the Naukluft mountains east of Sesriem, where the Naukluft Mountain Zebra Park was proclaimed in 1968 for that very purpose. Up there the species sort themselves by terrain: mountain zebra and rock hyrax on the steep slopes, kudu in the ravines, springbok, oryx and duiker on the plateaus.

Rock hyrax are easier to reach than that. In the Sesriem Canyon they sit on the rock ledges, along with baboons, the occasional snake and the many birds that nest in holes in the canyon walls. Walk it in the morning while there is still shade down between the walls.

Plants that dig deeper

The camel thorn (Vachellia erioloba, formerly Acacia erioloba) is the tree that defines the plain and the tree that has been standing dead in Deadvlei for centuries. Its trick is out of sight: in sandy ground the roots go down as far as 60 metres, until they hit groundwater. That is why it prefers ephemeral riverbeds such as the Tsauchab. Nothing else out there casts shade.

It is tough in other ways too. Annual rainfall anywhere between 40 and 900 millimetres suits it, as do daytime temperatures from under 15 degrees up to 45. The wood is hard, heavy and durable. That explains why the dead trees in Deadvlei are still upright after 600 to 700 years instead of having collapsed. Rot needs moisture, and there is none. Ground pods and a decoction of the roots are used traditionally against ear infections, toothache and tuberculosis. How Deadvlei came about is covered on the page about the formation of the Namib.

The nara melon (Acanthosicyos horridus) is endemic to Namibia and grows in a belt 40 to 60 kilometres wide along roughly 1,000 kilometres of coast between the Orange and the Kunene. The roots reach up to 30 centimetres in thickness and 40 metres in length. Leaves it has none: the thorns, two to three centimetres long, are reduced leaves, and photosynthesis happens in the branches, flowers and thorns. Very little water escapes that way.

The fruit is about the size of an ostrich egg, 15 to 20 centimetres across and over a kilogramme, with some 250 seeds in the flesh. In a landscape without water that is a meal everything gathers around. Giraffe, antelope, rhino, jackals and hyenas eat the fruit, while elephants and porcupines pass the seeds undigested. For the Topnaar along the Kuiseb the nara is a traditional staple, and Nama and Damara eat the fruit and dried seeds and use the plant against stomach pain, for wound healing and as sun protection. Nara Vlei near Sossusvlei carries its name.

Two further names keep turning up in travel writing about the region, and both deserve a footnote. Salvadora persica, the toothbrush tree, has long been used for cleaning teeth across Africa and Asia; we found no evidence for its occurrence specifically in the Sossusvlei region. And Euphorbia damarana, the Damara milk bush, counts among the most poisonous plants in Namibia, down to the smoke, which is dangerous for people to breathe. Oryx eat it anyway in times of drought, up to a quarter of their intake, because they can detoxify it. The study behind that comes from Damaraland rather than the southern Namib.

The welwitschia does not grow here

Few misunderstandings are this persistent. The welwitschia (Welwitschia mirabilis) is Namibia's botanical emblem, which is why plenty of travel sites file it next to the dunes of Sossusvlei. Its range ends in the south at the Kuiseb river near Gobabeb, far north of Sesriem. The heartland is the Welwitschia Vlakte in the triangle between the Khan and the Swakop, with the highest density 50 to 60 kilometres from the coast.

So plan the welwitschia in near Swakopmund, not near Sesriem. The plant is worth the detour in its own right: radiocarbon dating gave 500 to 600 years for the specimens measured, and extrapolation puts the largest ones at up to 2,000 years. The second popular claim about it is wrong as well. The welwitschia takes up no meaningful amount of fog water through its leaves, which are sealed far too tightly for that. Its water comes out of the soil.

Sociable weavers and the largest nests of any bird

A sociable weaver nest (Philetairus socius) looks as though somebody threw a haystack into a tree. Over four metres wide, well past a hundred separate chambers, room for up to 500 birds. A single nest can stay occupied for a hundred years, built on and on by one generation after another.

A whole society lodges in there: Kalahari skinks, praying mantises, other weavers, waxbills, small parrots, pygmy falcons, pearl spotted owlets and a pseudoscorpion found nowhere else. The range of the species covers central Namibia and the central Kalahari. As host plants the literature names quiver trees and telephone poles above all, and we could not confirm in writing that camel thorns around Sesriem carry these nests. If you pass a tree with a roof like that, you have your own answer.

When you actually see anything

The desert does not perform on request. It performs early. The outer gate at Sesriem opens at sunrise, and the hour that follows is the best of the whole day, for animals as much as for light. After that the ground goes quiet until the sun drops low again.

Drive the 60 kilometres to the car park slower than you have to. At 60 you see the oryx in the grass, at 100 you see grass. Pull over where grass patches run up against the dune foot, switch the engine off and wait five minutes before moving on. On the way back in the afternoon the sun sits low enough that tracks in the sand throw shadows again.

Nocturnal animals are largely out of reach on your own, since nobody is allowed inside the park after sunset. For geckos, sidewinding adders and scorpions, book a guided desert walk or a night drive through a lodge; the activities page has an overview. Everything else needs an early alarm, binoculars and a light foot on the accelerator.

Our tipGive the ground ten minutes at the dune foot instead of the horizon. Beetle tracks, gecko prints and the double line of an adder that stops dead in the sand are all there before your first coffee break, and the late morning wind takes every one of them.