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Explore why having many different types of species makes an ecosystem stronger.
Imagine a sports team where every single player was a goalie. No one to kick the ball, no one to defend, just eleven people standing in the net! Would that team win many games?
Biodiversity is the variety of all living things in a specific area. Think of it like a giant puzzle where every piece is a different species—plants, animals, fungi, and even tiny bacteria. When an ecosystem has high biodiversity, it means there are many different 'jobs' being done. Some plants turn sunlight into food, some animals spread seeds, and others clean up waste. If an ecosystem has different species instead of just , it is much more stable because if one species gets sick, there are others to keep the system running. This variety is what keeps our air clean, our water pure, and our food growing.
Imagine you are comparing two small gardens: 1. Garden A has tulips and nothing else. 2. Garden B has tulips, daisies, sunflowers, rose bushes, and milkweed plants.
Even though both gardens have total plants, Garden B has higher biodiversity because it has different species instead of just .
Quick Check
If a park has 200 squirrels and 200 oak trees, does it have higher biodiversity than a park with 50 squirrels, 50 oak trees, 50 birds, and 50 mushrooms?
Answer
No. The second park has higher biodiversity because it has 4 different species, while the first park only has 2.
Why does variety matter? It creates resilience, which is the ability of an ecosystem to 'bounce back' after something bad happens. Imagine a forest where every single tree is a Pine tree. If a specific 'Pine Beetle' arrives, it could kill every tree in the forest! However, in a biodiverse forest with Maples, Oaks, and Pines, the beetles might kill the Pines, but the other trees will survive. These survivors provide homes for animals and prevent the soil from washing away, allowing the forest to recover. High biodiversity acts like an insurance policy for nature.
A pond experiences a sudden heatwave that raises the water temperature. 1. Species A (a fish) cannot survive the heat and dies out. 2. Species B (a different fish) is naturally tougher and survives. 3. Because Species B survived, it continues to eat the mosquito larvae in the pond, preventing a mosquito outbreak.
This shows how having multiple species (A and B) kept the ecosystem balanced even when one failed.
Quick Check
What is the term for an ecosystem's ability to recover from a disaster?
Answer
Resilience.
Unfortunately, biodiversity is shrinking globally. Scientists have identified three major threats: 1. Habitat Loss: When we cut down forests or build cities, animals lose their homes. This is the cause of extinction. 2. Invasive Species: These are 'invader' plants or animals brought to a new place where they don't belong. They often take over and crowd out the local species. 3. Pollution: Chemicals in the water or air can make it impossible for sensitive species to survive.
When we lose even one species, it can cause a 'domino effect' that hurts many others in the food web.
Consider a food chain: Grass Grasshopper Frog Hawk. 1. If pollution kills the Frogs, the Grasshopper population will explode because nothing is eating them. 2. The massive amount of Grasshoppers will then eat all the Grass. 3. Without Grass, other animals (like rabbits) will starve.
One change at the 'Frog' level disrupted the entire system!
Which of these ecosystems likely has the HIGHEST biodiversity?
How does biodiversity help an ecosystem during a disease outbreak?
Habitat loss is currently the number one threat to biodiversity.
Review Tomorrow
Tomorrow, try to explain to a friend why a forest with 20 types of trees is 'stronger' than a forest with only 1 type of tree.
Practice Activity
Go outside and find a small patch of grass or a garden. Count how many different types of plants or insects you can find in 5 minutes. That is the biodiversity of your 'micro-ecosystem'!