Nothing in nature lives alone. Every plant and animal is part of a chain — and pulling one link out shakes the whole thing.
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A food chain shows who eats whom, and every chain begins with a plant.
🔗 The roles
| Role | Meaning | Example |
|---|---|---|
| Producer | makes its own food using sunlight | grass, trees, algae |
| Primary consumer | a herbivore that eats producers | grasshopper, deer, cow |
| Secondary consumer | eats the primary consumer | frog, snake |
| Top consumer | eaten by nothing above it | eagle, tiger |
| Decomposer | breaks down the dead | bacteria, fungi |
Every food chain starts with the sun. Only green plants can capture that energy, which is why they are called producers and why no chain can begin with an animal.
A food web, not a chain. In real life most animals eat several things, so the chains cross into a web. Remove one species and several chains are affected at once — which is why extinction matters so much.
An ecosystem is all the living things in a place together with their non-living surroundings. Each creature is fitted to its own.
🏞️ Fitted to the place
| Animal | Adaptation | For |
|---|---|---|
| Camel | stores fat in its hump, broad feet, little water needed | desert |
| Polar bear | thick fur, fat layer, white coat | snow |
| Fish | gills, streamlined body, fins | water |
| Cactus | spines instead of leaves, thick stem | desert |
| Yak | thick coat, large lungs | high cold mountains |
Why a cactus has spines. Leaves lose water. Spines lose almost none, and they also keep animals away. The thick green stem does the food-making instead.
Human activity can break a balance that took thousands of years to form.
⚖️ The words to know
| Word | Meaning |
|---|---|
| Deforestation | cutting forests down |
| Endangered | so few left that the species may die out |
| Extinct | none left anywhere on earth |
| Endemic | found naturally in one place only |
| Wildlife sanctuary | protected area where animals are safe |
| National park | protected area for the whole ecosystem |
| Biosphere reserve | a large protected region of many ecosystems |
Endangered is not the same as extinct. An endangered species still survives and can still be saved. An extinct one is gone for ever. The Asiatic lion in Gir and the one-horned rhino in Kaziranga are endangered; the dodo is extinct.
Project Tiger was launched to protect the tiger, India’s national animal, in its reserves. Protecting a top predator protects everything below it in the web.
12 questions on food chains, ecosystems and conservation. 🍀
