KS3 · Biology
Agriculture and habitat loss
Look at your plate. It all grew on land, or came from an animal that ate something grown on land. What was that land before it was a farm?
Palm oil
Reason it through
Why is the Sumatran orangutan now critically endangered?
First link · your turn
Where does palm oil come from, and what is it used for?
Run the web in reverse
A farmer lets part of a field be rewilded: native plants, including flowers and trees, regrow.
What happens to the area's biodiversity?
Biology · Responses
Repair it, or stop more loss?
Each response does one of two jobs. Does it put lost habitat back, or does it reduce the demand that causes more loss? Place each one, then read the reason.
Still to sort
Restores habitat that was lost (0)
Native plants and trees regrow on land.
Where the line is: If it puts plants and trees back on land, it is restoring.
Reduces the demand that causes more loss (0)
Changes what we choose, so less land is cleared.
Where the line is: Eating less meat is the tricky one. It belongs here, because it reduces the demand for land. The land it frees can then be rewilded or reforested, and that second step is the restoring.
WHAT YOU'VE LEARNED
A quick recap of today's lesson.
What you need to know
- Agriculture means using land to grow crops and to rear farm animals. Rearing animals has destroyed more habitat than growing crops.
Have a goPriya says a farm with only farm animals on it isn't 'agriculture', because nothing is being grown. Is she right?
No. Using land to rear animals is agriculture too.
Agriculture is not just growing crops, and rearing animals is the use of land that has destroyed more habitat.
- Our food comes from crops, edible plants and fungi, or animals that ate crops, so producing food depends on agriculture.
- The human population has risen rapidly over the last 200 years, so more food is needed and more land must be used for agriculture.
- Deforestation is removing trees, often for farming or building. Converting land for agriculture is a major cause of it.
- A habitat gives an organism food, shelter and a place to reproduce. Turn forest into farmland and that habitat is lost.
- Biodiversity is the range of different species in an ecosystem. A forest's is high, but a one-crop field's is low.
Have a goField A holds thousands of wheat plants. Forest B holds fewer plants but lots of different species. Which has the higher biodiversity?
Forest B.
Biodiversity counts different species, not how many plants there are, so a one-crop field is low even when it is packed with plants.
- Deforestation removes shade and shelter and disrupts food chains, so biodiversity is likely to decrease and some species may go extinct.
- Threatened species include pollinators, and many crops cannot be grown without pollinators to fertilise their flowers.
Have a goA town loses most of its pollinators. Why might the crops on its allotments struggle?
Many crops cannot be grown without pollinators to fertilise their flowers.
Crops are not separate from wildlife: the food needs the pollinators, so a threat to them is a threat to the crops.
- Palm oil is in many common foods. Its trees are grown on plantations after deforestation, and the Sumatran orangutan is now critically endangered.
- Reforestation and rewilding restore some habitat, but only a small proportion of what was lost. Changing diets can have a bigger impact.
The big picture
More people need more food, and more food needs more land. Turning forest into farmland removes habitats, so biodiversity falls, including the pollinators that many crops depend on. Restoring habitat helps, but only replaces a small proportion of what was lost, and changing diets can have a bigger impact.
Key points
Worked example
Problem
Trace each of these back to agriculture: a slice of bread, a mushroom, and a piece of cheese. How many ways does each one need land?
⚠ Watch out
A field packed with crops looks green and full of life, so it feels like high biodiversity. But biodiversity counts different species, and a one-crop field has just one. Lots of plants is not the same as lots of species.
Memory hook
Plate, farm, felled forest, fewer species, fewer pollinators, fewer crops. Follow your food back, and then notice the trail comes round again.
Check yourself
Cover the page and talk it through in four links: start with 'more people' and finish with 'the crops that need pollinators'. Then say which link turns back on the food you started with.
Flashcards
(14)What does agriculture mean?
Which has destroyed more habitat: rearing animals or growing crops?
Name the three kinds of source our food comes from.
What is deforestation?
What is a habitat?
What are biodiversity and an ecosystem?
A forest becomes a field of one crop. What happens to biodiversity, and why?
What does deforestation do to a forest's other plants and animals?
Why are pollinators important for food?
How does palm oil lead to endangered species?
What is the difference between reforestation and rewilding?
How much of the lost habitat do reforestation and rewilding replace?
Why can many people eating less meat help?
Which oils are more forest-friendly?
Tap any card to flip it, or use Study as deck to go through them one at a time. In the full lesson these run as a spaced-repetition deck — you rate each card Hard, Good or Easy and the tricky ones keep coming back until they stick.
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How this lesson was checked. This KS3 Biologylesson was published through Lightbulb Learning's human-designed editorial process — the educational standards, accuracy rules and publication checks it must pass were authored and approved by Philip Halpin. It passed subject-specific assessment, automated educational checks and technical publication verification before going live (publication checks completed 9 October 2026). Published pages are monitored, human spot-checking is ongoing across the lesson library, and anything found wrong is corrected or withdrawn. How our lessons are made and checked. Spotted a mistake? Email hello@lightbulblearning.co and we'll review it.