temehu: prehistoric sahara
Hundreds of millions of years ago the Sahara was covered by a great sea called the Tethys Sea. Around 40 million years ago the tectonic plates gradually began pushing Africa against Europe for 20 million years. Around 20 million years ago Africa collided with Europe and closed the Tethys Sea. As Africa continued to push against Europe northern Africa began to slowly emerge from the bottom of the sea; leaving behind a tropical swamp. Eventually the swamps turned into massive expanse of searing desert around 3 million years ago.
ThOUGHT CO: ANIMALS AND PLANTS OF THE SAHARA DESERT
Due to the high temperatures and arid conditions of the Sahara Desert, the plant life in the Sahara Desert is sparse and includes only around 500 species.
These consist mainly of drought and heat resistant varieties and those adapted to salty conditions (halophytes) where there is sufficient moisture.
The harsh conditions found in the Sahara Desert have also played a role in the presence of animal life in the Sahara Desert. In the central and driest part of the desert there are around 70 different animal species, 20 of which are large mammals like the spotted hyena. Other mammals include the gerbil, sand fox and Cape hare. Reptiles like the sand viper and the monitor lizard are present in the Sahara as well.
ANIMALS
When you think of a desert, do you imagine a lifeless wasteland where nothing can survive? While many people think of deserts as lifeless locations, they are actually quite diverse and rich in life.
In fact, it could be said that there is no finer example of the richness of evolution than a desert ecology. Why? The harsh conditions imposed by the desert climate force desert inhabitants to adapt. The fact that many species of plants and animals thrive even in these conditions is a great testament to the resourcefulness of life. Here are some amazingly adaptive Sahara desert animals.
CAMELS
Dromedary camel SOURCE DesertUSA
Camels store a large amount of fat in the humps on top of their backs The fat can be burned for energy when the camel is unable to locate any food. While most of us are searching for ways to burn off fat and slim up our bodies, camels are actually evolved by nature to carry extra fat around to survive
ADDAX ANTELOPE
Addax Antelope (Sean Abbott/Flickr) Source Conservation Institute
Addax antelope is well known for its sleekness and its beauty. They are among the most endangered animals on the planet, with long, elegant horns and flat feet. Sadly they have been hunted to the point where there are only around 500 left. (Slide Share)
RED NECK OSTRICH
Image World ATlas
Not a lot of people think of ostriches when asked to name a desert animal, but ostriches are some of the fastest animals in the Sahara. They are able to run up to 40 miles an hour, almost as fast as the gazelles. They can travel a long ways, and can also pick up noises and see movement across vast distances, helping them spot and avoid predators. When threatened, the ostrich can fight back, kicking with its long legs. (The Biggest Animals Kingdom)
The North African ostrich (Struthio camelus camelus) is the largest living bird in the world. It grows up to about 9 feet in length, has a pinkish-red neck, black/white plumage in males and gray plumage in females. Hunting for food, capture for farming, loss of habitat, etc., has led to the rapid decline of the population of this ostrich. The species is now found in only 6 of the 18 countries where it once existed. (World Atlas)
FENNEC FOX
Image Go Pets America
The Fennec Fox (Vulpes zerda) is the smallest of all foxes (40 cm in length with an additional 30 cm of tail). It is a strict desert inhabitant of the Sahara and Arabian deserts being particularly common in dune habitats.
The Fennec fox is superbly adapted to the life in the desert. It has strong forepaws for digging and densly furred soles to protect the feet from hot sand. Their dry feces and concentrated urine allow them to reduce water loss and survive indefinitely without free water. The large ears are perfect for heat loss and excellent hearing makes it easy to detect prey. Their thick fur serves as a perfect insulator against cold night air.
The fennecs have weak teeth and feed mostly on insects, but also consume eggs, small vertebrates, roots and fruits.
These foxes are most commonly seen in pairs but up to 10 animals have been recorded in a group. About 5 blind and helpless young are born in a burrow and are mature by 6 months. Captive fennecs are very vocal and sociable.
The Fennec fox is heavily hunted in the Sahara. They are also captured live and marketed as food. Wherever domestic and wild dogs and cats are present their populations become at risk. As a consequence, their numbers are declining. (Go Pets America)
JERBOA
Image Pinterest
These adorable little rodents have very long legs and can jump very high. Despite their minuteness, they can run up to 16 miles per hour, making them quite challenging to catch. Amazingly, the jerboa doesn’t have to drink water—quite a useful adaptation for a desert creature. It still needs to take in water of course, like all living things, but it is able to extract enough from its foods to sufficed for its needs. (Conservation Institute)
DEATH STALKERSCORPION
Image Death Stalker Scorpion (Art/Flickr)
This type of scorpion is translucent and yellow in appearance, and is among the most venomous animals of the Sahara desert, and the entire world. They look ephemeral and fragile, but they are incredibly dangerous, capable of causing respiratory failure and death. (Conservation Institute)
DORCAS GAZELLE
Image Animal A Day
Also known as the Ariel Gazelle, this animal is sleek and graceful, usually weighing around 25 kilograms. Many animals in the Sahara desert prey on gazelles, so the Dorcas gazelle has evolved to avoid them on impulse. When a predator approaches, the gazelle’s highly attuned body will automatically jump. This is known as “stotting.” It serves several purposes. Firstly, it gets the gazelle out of immediate danger. Secondly, it demonstrates the gazelle’s speed and reflexes to the predator, discouraging it. Thirdly, it alerts other gazelles that a predator is approaching. If the gazelle is forced to run, it can achieve an astounding 49 miles per hour. (Conservation Institute)
Designated as vulnerable by the IUCN, only 35,000-40,000 of these animals exist today. The dorcas gazelle is well-adapted to life in the desert. It can go without drinking for its entire lifetime, but when water is available, it does drink water. These gazelles are active between dusk to dawn when they forage for leaves, fruits, twigs, and flowers of desert vegetation.
The critically endangered species of gazelle, the dama gazelle (Nanger dama) is today found only in Niger, Chad, and Mali though earlier it had a more widespread distribution. Hunting for meat and habitat loss threatens the survival of this species. These gazelles feed on leaves, fruits, grasses, and shoots of desert plants. (World Atlas)
SIDEWINDER/ SAND VIPER
Image LudicArs
There are a number of species of sidewinder in various deserts around the world. The horned viper is particularly well known in the Sahara. The venom from this snake can be lethal, and also quite painful, even in cases that do not lead to death. The unique sideways movement of the sidewinder helps it to traverse the sands quickly and effectively. Sadly, changes in the environment have caused the horned viper to enter the endangered species list. (Conservation Institute)
DESERT CROCODILE
When we speak of “What animals live in the Sahara Desert?” we hardly think of crocodiles. However, the West African crocodile (Crocodylus suchus) inhabits the desert habitat where it remains in a state of aestivation during periods of drought, hidden away in the safety of caves and burrows. During the rainy season, the crocodiles emerge from their shelter and gather at gueltas. (World Atlas)
MONITOR LIZARD
The desert monitor (Varanus griseus) is a carnivorous lizard species found in the Sahara Desert habitat. This animal is a cold-blooded creature and hence goes into hibernation from September to April. The lizards grow up to 1-2 meters in length and have an average lifetime of about eight years in the wild. The desert monitor feeds primarily on rodents, fish, and eggs but it might also feed on birds, small mammals, and other creatures if the opportunity arises. (World Atlas)
AFRICAN WILD DOG
Image Animal Adda
An endangered species, the African wild dog (Lycaon pictus) is native to sub-Saharan Africa. Today, only 39 subpopulations of this canid species exist comprised of 6,600 adults. Outbreaks of infectious diseases, persecution by humans, and habitat destruction are responsible for the decline in African wild dog populations. These animals are highly social, living and hunting in large packs. Uniquely, it is the females of this species that leaves the pack when sexually mature instead of the males. Antelopes are their primary prey.
AFRICAN SILVERBILL
Image The Internet IBC Bird Collection
The African silverbill (Euodice cantans) is a bird that lives in arid landscapes. It is a resident bird of dry savanna regions of Africa bordering the Sahara Desert. The African silverbill is a sociable bird that perch atop trees in large flocks often huddled close together for long periods of time. They feed on grass seeds and seeds of growing plants. (World Atlas)
BLACK-FACE FIREFINCH
Image Avitoon
The black-faced firefinch (Lagonosticta larvata) is a common bird belonging to the estrildid finch family of Africa. This species can be sighted in many countries of sub-Saharan Africa. Currently, the bird is classified as Least Concern because of its widespread distribution. However, populations of this bird are estimated to be declining steadily. (World Atlas)
PLANTS
Seeds sprout quickly after a rain and attempt to complete their growing cycle before the soil dries out. SOURCE desertusa.com
With high temperatures and strong winds, cloudless skies and low humidities, the little rain that does fall is quickly evaporated. Everything and everyone is threatened by dehydration. So the key to survival here — the survival of plants, animals and human beings — is the ability to obtain enough water, and to avoid losing it. The diversity of plant and animal species is inevitably limited, but they display a wide range of strategies for survival. (Wild melons on the Hoggar Massif) Source John Tyman
Much of the central Sahara averages less than 20 mm annually. Most perennial plants simply cannot survive under these conditions. Such areas can only support annuals. These spring up after heavy rain, when the desert will briefly be green: but they will flower and seed quickly, wilt and die — living on as seed lying dormant in the soil. (Plant in seed in the Tassili-n-Ajjer) SOURCE John Tyman
Some plants have thorns instead of leaves, offering a smaller surface area from which water can be evaporated. Others store the water that falls in the occasional thunderstorm. The Sahara lacks the cacti of American deserts, but it has comparable succulent species. And plants in shaded locations can survive on less moisture. (Flowering plant at foot of narrow steep-sided wadi in the Sinai) SOURCE John Tyman
Though the surfaces of most desert soils are dry year-round (save for days following the occasional rains) there is often a damp layer within the soil profile and also water in the crevices of underlying rocks. Together they are capable of supporting a few perennials, though these may need to adapt to a high salt content. In the heat of the day, though, many plants will wilt, so that the surfaces of their leaves are no longer at right angles to the sun. (Stressed perennial near Ain Khudra in the Sinai) SOURCE John Tyman
Trees and shrubs are rare, found only where their roots can reach ground water, as in wadisoccupied briefly by intermittent streams following rain. (Floor of wadi in the Hoggar after rain) SOURCE John Tyman
The tamarisk, or “salt cedar”, is the commonest species of tree found in the Sahara. It is evergreen and typically between 5 and 15 metres in height. Its presence is an indication that there is ground water to be found here at a depth of between 5 and 15 metres. (Tamarisk bluff near Ideles) SOURCE John Tyman
Acacias, too, are deeply rooted. In contrast the roots of succulents typically extend for only 3-4 cm beneath the surface so they can make the most of every shower even when the rain does not sink very far into the ground. (South of Illizi) SOURCE John Tyman
Most plants also collect water from a wide area and so are spaced far apart. Only in an oasis will you find areas of continuous plant cover: everywhere else plants are widely scattered. (North of In Amenas) Source John Tyman
Acacias, too, are deeply rooted. In contrast the roots of succulents typically extend for only 3-4 cm beneath the surface so they can make the most of every shower even when the rain does not sink very far into the ground. (South of Illizi) SOURCE John Tyman
AFRICAN PEYOTE CACTUS
Image Natural.Lum
African Peyote Cactus thrives in the desert environment. Its thick stems retain water for long periods of time. Its spiny leaves help prevent water loss because of evaporation. Native Saharan tribes use peyote from this plant in their spiritual rituals. Every time it rains, the African peyote cactus collects water, storing it in their thick stem and until it rains again, that is all they survive on. It lives with very little sun and prefers soil with a PH of 6 or 7. The plant can be started from seeds or the shoots of an older plant. (Sahara Desert Project 1)
DATE PALM TREE
Date palm (Phoenix dactylifera).© Stephan Geisler/Fotolia Source Britannica
Palm Trees mostly grow in areas where the water is closer to the surface. These types of trees are arranged in narrow lines and are oriented east to the west. The desert palm is found close to settlements where people dig wells to get water. (Sahara Desert Project 1)
DOUM PALM
The doum palm (Hyphaene thebaica) is another plant of the Sahara Desert that grows along the Nile River. It bears an edible red-orange oval fruit, whose taste resembles that of gingerbread, and thus the tree is also called “gingerbread tree.”.
The importance of the doum palm can be gauged from its versatile uses; no portion of this plant goes to waste.The white nut of the plant’s fruit is made into buttons by the natives.Then comes the rind of the fruit, which is used in preparing molasses, sweetmeats, and cakes.Lastly, the leaves of the palm are used for making paper and mats.The doum palm has medical uses as well. The nut of its fruit is grounded to dress wounds and an infusion of the fruit is believed to help manage high blood pressure. (Buzzle)
OLEANDER
Image Pixabay.com
Also known as Nerium oleander, the plant is an evergreen shrub. Although the shrub is widely cultivated in the Sahara, it has a sporadic growth. The shrub bears flowers, which can be white, pink, or red in color. Oleander is known for its rapid growth and sweet scent. Furthermore, it is a commonly grown indoor plant and one of the most poisonous houseplants too. (Buzzle)
OLIVE TREE
Image The Sahara Desert
The Olive Tree is an important tree that grows in many places along the Nile River in North Africa. People cultivate this tree for oil, which is used for cooking. The Olive Tree is able to survive in the hot dry climate because its small leaves have a protective coating that slows water loss. (Sahara Desert Project 1)
THYME
Image Quest Nature Tours
The soil of the Sahara Desert is home to a drought-resistant herb called thyme (Genus: Thymus).Apart from being a major food source for the animals of the desert, thyme is commonly used in African and Middle Eastern cuisines.
~ Medicinally, this herb is used for treating indigestion, respiratory infections, and spasms. (Buzzle)
COMMON FIG TREE
Image Vivai Sansone
Suited for the Mediterranean climate, the common fig (Ficus carica) tree is also listed among the plants of the Sahara.The tree is capable of thriving in soil that is nutritionally poor and is tolerant to seasonal drought, thanks to its deep-rooted system.The reproduction of the fig tree depends on the pollination carried out by a certain species of wasps. (Buzzle)
TEMEHU: But how do plants survive in the desert?
For plants to survive in the desert, they must invent ingenious ways to deal with lack of water. Some species germinate within 72 hours of rainfall and sow their seeds 2 weeks later. Shrubs and trees have extensive root systems which can penetrate as far as 50 metres into the ground; tamarisk and acacia have short, fat trunks that act as reservoirs for excess water. The seeds of ephemerals germinate only after heavy rain, and then very quickly consume their entire life-cycle; producing brightly coloured flowers to attract insects. Grasses develop large and complex root systems for collecting water over a wide area, enabling them to survive when the overground parts are scorched to death.
Geophytes survive by remaining underground as bulbs, and like ephemerals, they quickly grow and develop when rain comes. Saharan succulents, like euphorbia, suck the extra water to store for later. Some insects collect moisture from the air and then direct it as droplets of water into their mouths. While desert-ships (the camels) vary their bodies’ temperature according to the conditions: low when it is cool and high when hot; when they are thirsty transpiration drops to zero. Humans, however, resort to nomadic way of life in order to survive in the Sahara, travelling from one location to another in search of water and vegetation. In short, life has a mind of its own, long before it created ours!
The only permanently inhabited zones in the Sahara are the oases and areas along the few fertile valleys, such as Wadi Alhayat (the Valley of Life) in Fezzan. The palm trees in these regions, which are normally arranged in narrow rows with an east-west orientation (in line with the apparent sun’s course across the sky), occur where water is relatively close to the surface, and thus allowing the digging of shallow wells to support settled life. Rain in the Sahara falls at rare intervals, mostly between the months of January and April, with a variation from 0.5 inch to 4 inches over a 5 year period.
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