What Is Competition?

Competition occurs when organisms fight for limited resources in an ecosystem. The better adapted an organism is, the more likely it is to survive and reproduce.

💡 Key Concept: “Survival of the fittest” – the most successful competitors pass on their genes.

Types of Competition

What Do Animals Compete For?

✔ Food – to gain energy
✔ Water – for hydration
✔ Shelter or territory – for safety
✔ Mates – to reproduce

What Do Plants Compete For?

✔ Light – for photosynthesis
✔ Water – for transporting nutrients
✔ Mineral ions – for healthy growth (e.g. nitrates for proteins)
✔ Space – to grow and spread roots

Adaptations and Competition

Organisms that are better adapted to their environment will outcompete others.

Examples:

• Cacti have thick stems to store water and spines to reduce water loss.
• Lions have sharp claws and teeth for catching prey.
• Trees grow tall canopies to reach more light.

💡 These adaptations increase an organism’s chances of survival in competitive environments.

Invasive Species

Non-native species introduced to a habitat can outcompete native species if they are better adapted.

💡 Example: Grey squirrels outcompete red squirrels in the UK.