Planet Earth 2- Deserts
Guest Blog by: Michael McCoy
Deserts cover around one third of the land on planet Earth. In order to survive these ecosystems, you must be able to adapt to the dry and warm conditions which are extremely harsh. The two main challenges of the desert is being able to cope with a lack of water and endure very hot conditions.
Some Lions survive in the scorching sun in the Namib desert by having a very light-coloured, thin coat of fur to reduce the amount of heat stored. When hunting, Lions work together in what is known as a pride to capture any prey it comes across. The whole pride must work together in order to succeed as each have their own role. Some individuals chase the targeted prey while others move ahead to cut off any escape routes. Lions would travel long distances in search of food and can go many, many days without eating. Similarly, years ago, Humans hunted in groups and built traps of their own to capture prey. In today’s age however many animals that are consumed will be domestically raised on farms. This takes away the need to waste energy and time on hunting.
Cactus plants are the most successful vegetation in the desert. Many plants require a large amount of water and so cannot live during long periods of drought. However, the Cacti have found a way by storing large amounts of water in the stems of the plant. They also have no visible leaves as they want to greatly reduce the amount of water lost through rapid evaporation. To prevent animals from stealing the water stored and herbivores from consuming them, the Cacti developed spines to block any attempt of feeding. Spines also have a secondary use as they provide shade and so lower the surface temperature of the cactus, preventing loss of water. Although humans must excrete a lot of water as waste and thus cannot retain high amounts, we have been able to contain large quantities of water externally for drinking. We have been able to create large tanks of water to store with pipes which transfer water to people’s homes. Many people even collect rain water and utilise this for domestic purposes.
While it is rare for rain to occur in the desert, there are times when watering holes are created, drawing in many animals. Sandgrouse are one of these species that benefit from the watering holes. When the Sandgrouse chicks are born, they rely on the father to obtain water for them. The father flies miles to reach a watering hole along with an entire flock of males who share the same purpose. The Sandgrouse use their feathers which have been specialised for soaking up water and storing it like a sponge. The only problem is that it takes time to store the water and so many predators use this as an ideal opportunity to strike. Goshawks are the main birds that prey on the Sandgrouse, however, as the Sandgrouse travel in large flocks it is difficult for the Goshawk to select a target. By staying in large numbers the Sandgrouse are less likely to be attacked by their predators. Although Humans nowadays who live in wealthy countries usually have easy access to water, this was not always the case as years ago, tribes had to collect water in large containers from nearby rivers. These containers were heavy and had to be carried on their back for miles. In economically poor countries, this is still the case as children would have this vital duty to help their families survive in warm climates.
The island of Madagascar is very unique with many different habitat types, one of these is a dry desert. However, heavy showers lasting short spells can help create a greening of the land, resulting in a large diversity of plants and animals. One species which takes advantage of this greening is Locust. These insects swarm together in large numbers and destroy almost all vegetation in their path. The Locust become even more efficient and travel further when they grow wings and take to the sky. Once in every decade a super swarm can come about which covers two square miles and have over several billion individuals. These super swarms can leave lands barren and they can also destroy crops that local farmers are growing. This can cause many countries like Madagascar to have food shortages which could create a National emergency. The Food and Agriculture Organisation (FAO) helps to try and stop these Locust plagues before the land can be destroyed. Humans must adapt fast to plagues and act quickly if they are to minimise the impact. Experts are able to track locust movements and predict where the swarm will move next. The use of helicopters help with transportation and identify the swarm size. Many crops now have been sprayed with chemicals known as pesticides to get rid of unwanted insects feeding on their crops.
Many civilisations have adapted to the conditions of the desert. For example the use of light clothing to produce less heat as well as the need to find shade. Humans would also build houses and roofs to create shade and stay cool. This idea was based on animals behaviour. The Shovel-snout lizards would spend little time out in the open and would bury themselves below the surface of the sand where it is cooler.
Due to Climate change the world deserts are heating up and so are expanding across many continents, especially Africa. This will be interesting to see how humans and animals who are not familiar with the changing landscape, adapt in order to survive to an ever increasingly hostile environment.