Exploring grasslands in Africa to examine the plants and animals living in the tropical savanna biome.
Video
You may have seen lions, elephants and snakes in the zoo but if you wanted to see these incredible animals in their natural habitat you’d need to visit a tropical grassland, or a savanna.
These animals are best adapted to vast expanses of grassland with scattered trees, where the climate is hot, year-round. Savannas cover almost half the surface of Africa and large areas of Australia, South America and India.
So what makes a savanna special? One important factor is they have a wet season, lasting for about six months of the year. During this period the majority of the rainfall for the year occurs - reaching 1200mm. If the rainfall for the year was evenly distributed the area would become a tropical rainforest. In the African savanna region October signals the beginning of the dry season and - ironically - Mother Nature marks this with a series of violent thunderstorms, followed by a strong, dry wind.
Fires are widespread by January, which cooks up grub - such as stick insects and grasshoppers. Larger animals are usually able to run fast enough to escape the fire and can feast on the insects and animals that have been killed.
Another benefit to the fires is that the ash provides nutrients to the soil, that gets washed in by the rains. Fires clear away dead grasses and a flush of new life is experienced.
The trees found in these biomes across the globe have to cope with long periods of drought and fire, which wouldn’t be ideal conditions for your average horse chestnut. Fortunately trees - such as this baobab - have adapted so that it can grow up to 25m tall and live for thousands of years. The Sunland Baobab in South Africa is thought to be 6000 years old! It adapts to the environment, remaining leafless for 9 months of the year. Water is stored from the wet season in its bulbous trunk. It’s thick, corky bark resists fires - clever, eh?
Similarly, grasses have adapted to save their bacon. Some are bitter-tasting, to stop animals from grazing on them. And many - such as Bermuda grass - grow with long roots from the bottom up, so that the growth tissue doesn’t get damaged by peckish animals or fires.
A lion may be the first savanna animal you think of. Its dirty beige-coloured fur provides perfect camouflage for sneaking up on prey and they can run up to 40mph to catch gazelles, buffalo and zebra. Their sharp teeth and claws are perfect for grabbing and chomping up dinner!
The world’s deadliest snake also likes to call the savanna home. The black mamba can grow up to 4.5m in length - that’s nearly the length of two full-sized football goals! And it can travel at speeds of up to 12mph! Keep well away though - you wouldn’t want to get close!
One animal that doesn’t mind getting close to it is the mongoose, which will eat baby black mambas for breakfast! It’s curved and sharp claws help them to dig for food. Its loose, dense fur acts as armour and its colour blends in with the surroundings. In fact, they pretty much have an in-built survival kit!
Humans use savannas as a source of food, as well as for fibre and wood production. They mine extracts of valuable minerals from parts of the savanna and have transformed savannas into national parks, tourism areas and urban developments. Some parts are used for animal grazing.
It’s a spectacular, deadly world in the savanna - where all the plants and animals have finely tuned their survival tools to play their part in the ‘circle of life’. I don’t fancy my chances against this lot though!
Video summary
Download/print a transcript of the video.
Focusing on tropical grasslands in Africa, along with its plants and animals.
Ferne Corrigan looks in-depth at the climate of the African savanna grasslands, describing the rainfall distribution and the benefits of fires in the dry season.
The adaptations made by the baobab tree to survive in the Savanna are explained.
The focus then shifts to the unique features of different types of grass, along with the survival skills developed and adaptations made by lions, the black mamba and the mongoose.
A final look is taken at how humans have used the savanna grasslands.
This clip is from the series Ecosystems and Biomes.
Teacher notes
Download/print the Teacher Notes for this episode (pdf).
Before watching the video
Look at a map of the distribution of tropical savannas. Ask students to look for a pattern in the distribution and discuss why the tropical savanna is located where it is.
Ask students about the types of animals that they think might live in the tropical savanna and what type of climate they live in. Students could make predictions, which they could then add to once they have watched the film.
Introduce key terms such as:
Savanna: A grassland in tropical and subtropical areas, for example the Serengeti in Kenya and Tanzania.
Seasonal rainfall: Rainfall that only occurs in one part of the year.
Adaptation: A characteristic that enables an animal to survive in particular location or climate.
Grazing: Allowing livestock such as cows to feed on the vegetation in a location.
During the video
You may wish to stop at relevant points during this short film to pose questions and check understanding or wait until the end. Useful questions might include:
- Where are tropical savannas found?
- What type of climate does the tropical savanna have?
- Why are there fires in the tropical savanna?
- What are the benefits of the fires?
- What conditions do the trees have to cope with?
- How are the baobab trees adapted to living in the tropical savanna?
- What animals live in the tropical savanna?
- How are the animals adapted to living in the tropical savanna?
- How do humans use the tropical savanna?
After watching the video
Ask students to look back at their predictions, were they right about what they thought they would see in the tropical savanna? Students could complete a spider diagram to note down the basic information about each of the tropical savanna characteristics: vegetation, climate, animals and human uses.
Give students an image of the baobab tree and ask them to annotate it with the adaptation, for example the thick corky bark and the lack of leaves for 9 months of the year. Discuss with students how those adaptations enable the trees to survive in the climate of the savanna. Students could also compare this to another tree found in the tropical savanna, called the acacia tree. What similarities and differences do the two trees have?
Discuss the human uses of the tropical savanna. Ask students whether they think those uses are good for the savanna or if they will cause issues. Students could then rank the uses from most damaging to least damaging using their opinion and then writing up their decision.
Where next?
Compare the tropical savanna to a contrasting biome such as the tundra or the boreal forest.
Students could compare:
- Animals
- Vegetation
- Climate
- Human uses
A case study could be built for the savanna using a real-life example such as the Serengeti. This could form a research task which students could then present to the class.
Curriculum notes
This clip will be relevant for teaching Geography at KS3 and GCSE.
This topic appears in OCR, Edexcel, AQA, WJEC KS4/GCSE in England, CCEA GCSE in Northern Ireland, Progression Step 4/5/GCSE in Wales, and SQA National 4/5 in Scotland.
More videos from this series
How animals have adapted to live in the Arctic tundra. video
How people, animals and plants have adapted to survive the harsh Arctic tundra biome.
How animals have adapted to live in the Italian Alps. video
How plants, animals and people have adapted to an Alpine mountain region of Italy.
How animals have adapted to live in the polar biome. video
How animals have adapted to survive the freezing conditions of the polar ecosystem.
