2ND GRADE SCIENCE • INTERDEPENDENT RELATIONSHIPS IN ECOSYSTEMS

Which Place Has More Kinds of Living Things?

Let's explore two different habitats and figure out which one has a bigger variety of plants and animals!

What's Happening?

🔍 LOOK AT THIS!

Then you visit a rainforest. You see monkeys, frogs, parrots, butterflies, tall trees, vines, ferns, and colorful flowers. There are so many different living things everywhere you look!

💭 THINKING QUESTIONS
  • Which place has more kinds of living things?
  • Why do you think one place has more than the other?

What Scientists Know

A habitat is a place where plants and animals live. Different habitats have different kinds of living things.

Diversity (say: dih-VER-sih-tee) means how many different kinds of living things are in one place. A place with many different kinds of plants and animals has greater diversity. A place with only a few kinds has less diversity.

1

Habitats Are Different

A forest, a pond, a desert, and an ocean are all different habitats. Each one has its own plants and animals. Some habitats have lots of different kinds. Some have fewer.
2

We Can Observe and Count

We can look at a habitat and observe (that means watch carefully) what lives there. When we count the different kinds of living things, we are collecting evidence. Evidence helps us compare.
KEY TAKEAWAY
KEY TAKEAWAY

Let's Explore!

🔬 LET'S TRY IT!

What you need: Your eyes, paper, and a crayon or pencil.

1
Step 1Pick two spots to observe. One could be a sidewalk crack. The other could be a garden or a tree area.
2
Step 2Look carefully at each spot for 5 minutes. What living things do you see? Bugs? Plants? Birds?
3
Step 3Draw or write each different kind of living thing you see at each spot.
4
Step 4Count the different kinds at each spot. Which one had more? That spot has greater diversity!
My Observation Chart — comparing a sidewalk crack (2 kinds) to a garden (5 kinds)

The garden had 5 different kinds of living things. The sidewalk crack only had 2 kinds. Our evidence shows the garden has greater diversity!

What We Found Out

When we observe a habitat and count the different kinds of living things, we are collecting evidence. Evidence is the information we get from watching and recording.

We use evidence to compare two habitats. We ask: Which habitat has more different kinds of plants and animals? The answer tells us which one has greater diversity.

HABITATLIVING THINGS OBSERVEDNUMBER OF KINDS
Desert 🏜️Lizard, cactus, brown bird3
Rainforest 🌿Monkey, frog, parrot, butterfly, tree, vine, fern, flower8

Look at the data! The rainforest has 8 different kinds of living things. The desert has only 3 kinds. The evidence clearly shows the rainforest has greater diversity.

Why does the rainforest have more kinds? It has lots of water and warm weather all year. Many plants can grow. When there are many plants, there is food and shelter for many kinds of animals too!

Do You See the Pattern?

Scientists look for patterns. A pattern is something that happens the same way again and again. Let's look for a pattern about diversity!

HABITATWHAT IT'S LIKEDIVERSITY
🌿 RainforestWarm, lots of rain, many plantsHigh — many kinds
🌊 Coral ReefWarm water, lots of foodHigh — many kinds
🏜️ DesertVery dry, very hotLow — few kinds
❄️ Ice SheetVery cold, almost no plantsLow — few kinds

Do you see it? Here is the pattern: Habitats with more water, food, and shelter tend to have more different kinds of living things. Habitats that are very harsh — very hot, very cold, or very dry — tend to have fewer kinds.

This pattern shows up everywhere in nature! Even in your own neighborhood. A park with trees and a pond will have more kinds of living things than a parking lot.

KEY TAKEAWAY
KEY TAKEAWAY

This Matters in the Real World!

People use what we know about diversity to help take care of nature. Scientists go to different habitats and observe what lives there. They count the different kinds of plants and animals. This helps them figure out which places need protection.

If a forest used to have many different kinds of animals but now only has a few kinds, scientists know something is wrong. Maybe the trees were cut down. Maybe the water got dirty. They use their evidence to figure out how to help.

🌱 You Can Help Too!

Words to Know

📖 KEY VOCABULARY
  • Habitat — A place where plants and animals live, like a forest, pond, or desert.
  • Diversity — How many different kinds of living things are in one place.
  • Observe — To watch something carefully and notice details.
  • Evidence — Information you collect by observing. It helps you explain what you see.
  • Compare — To look at two or more things and see how they are alike or different.

Practice: Show What You Know!

1
A student visits two parks. At Park A, she counts 2 kinds of birds and 1 kind of insect. At Park B, she counts 5 kinds of birds, 3 kinds of insects, and 2 kinds of lizards. Which park has greater diversity of living things?
2
Two students observe living things in two different schoolyard areas. Area 1 (near a garden) has butterflies, ladybugs, earthworms, sparrows, and dandelions. Area 2 (on the blacktop) has only ants and pigeons. What is the best evidence that Area 1 has greater diversity?
3
Maria observes a sandy beach and a rocky tide pool at the ocean. At the beach, she sees seagulls and crabs. At the tide pool, she sees sea stars, snails, small fish, crabs, seaweed, and sea anemones. Maria says, "The tide pool has greater diversity." Which observation best supports her claim?
4
Jamal's class observed two habitats near their school. They made this list:Meadow: rabbits, grasshoppers, wildflowers, mice, hawks, clover, beetlesParking lot: sparrows, dandelions, antsWhy does the meadow most likely have greater diversity than the parking lot?

What's Next?

🔮 WHAT'S NEXT?
Varsity Tutors • 2nd Grade Science (NGSS) • Habitat Diversity