Lesson video

Hello, everyone, how are you today?

I hope you're feeling really good.

My name is Ms. Afzal, and I'll be your teacher for this lesson.

I'm feeling really good about that because we have an interesting topic ahead.

We're looking at animals and animal classification.

I wonder if that's something you've heard about much, what your experiences of classifying animals.

Don't worry whether you have or you haven't.

We're going to get right into it today.

Our lesson is called How and why we group animals, and it comes from the unit of work Why we group and classify living things.

So, if you are ready to get into classification, if you got focus, energy, and enthusiasm, we'll begin our lesson now.

The outcome for today's lesson is, I can explain how animals can be grouped using observable characteristics.

I hope that sounds of interest to you.

We have some keywords in our lesson.

I'd like us to go through them one at a time, saying them out loud.

My turn, your turn.

Classify.

Identify.

Vertebrate.

Invertebrate.

Classification key.

Good to hear those words loud and clear.

Pause here and share with someone nearby.

Have you heard of any of these words before or do you even know what they mean?

Thanks for sharing.

Let's find out the meanings of these keywords.

To classify is to sort into groups.

To identify something is to be able to name it correctly.

A vertebrate is an animal with an internal skeleton including a spine.

Animals that do not have bones, including a spine, on the inside of their bodies are invertebrates.

Classification keys are diagrams which help us sort things into different groups.

These are our keywords, classify, identify, vertebrate, invertebrates, and classification keys.

Let's look out and listen out for them.

Let's think carefully about them.

They'll be coming up in our lesson today.

Today's lesson is called How and why we group animals, and it has three learning cycles, vertebrates and invertebrates, groups within vertebrates and invertebrates, and creating classification keys.

Let's begin by exploring vertebrates and invertebrates.

There are millions of species of animal living on planet Earth, and scientists are discovering ones all the time.

How incredible.

Scientists classify or group animals to make it easier to identify, name, and learn more about them.

Scientists who specialize in identifying and classifying animals are called taxonomists.

Here is a taxonomist observing an animal.

When a new animal is discovered.

taxonomists look at the similarities and differences between it and other animals to decide which group it belongs in.

Do you know any names of the groups taxonomists use for different animals?

Pause here and share with someone.

Thanks for sharing.

One way taxonomists can classify animals is by sorting them into vertebrates and invertebrates.

Pause here and share with someone.

Can you remember what is the difference between a vertebrate and an invertebrate?

Thanks for sharing.

Vertebrates are animals that have a spine or backbone and an internal skeleton.

Here are some vertebrates.

And invertebrates do not have a spine or internal skeleton, and there, we can see some on the screen.

Andeep fell when playing on his skateboard.

At the hospital, a radiographer took an X-ray to examine the bones in Andeep's knee.

Now, we can see an X-ray of a human knee.

"I know that humans are vertebrate animals.

I wonder if X-rays of other animals can help me to identify which are invertebrates.

" Let's ask a question to help us find out.

Which statement do you agree with?

Choose from this selection.

a, an X-ray will only show the bones of a human skeleton.

b, an X-ray of an invertebrate will show no bones.

c, an X-ray of an invertebrate will show only a spine.

d, an X-ray of an invertebrate will show some bones but no spine.

Pause here while you decide, which statement do you agree with?

Well done if you selected statement b.

Indeed, an X-ray of an invertebrate will show no bones.

Let's have another check for understanding.

Which of these animals are invertebrates?

Choose from this selection.

a, human, b, shark, c, caterpillar, d, worm, e, crocodile.

Pause here while you decide which of these animals are invertebrates.

Well done if you selected caterpillar and worm.

Here's Jun, "If invertebrates don't have skeletons, how are their bodies supported and their organs protected?

" Good question.

Pause here and share with someone.

Do you have any ideas?

Thanks for sharing.

Some invertebrates have a hard outer covering that protects their body.

This is called an exoskeleton.

And here, we can see some invertebrates with exoskeletons.

As the animal grows, they molt their exoskeleton, and their fresh outer layer hardens to form a new, larger exoskeleton.

Some invertebrates have a body filled with fluid that supports their body and helps them to move.

This is called a hydrostatic skeleton.

Here, we can see some invertebrates with hydrostatic skeletons.

What incredible creatures.

Let's have a check for understanding.

Which of these invertebrates have hydrostatic skeletons?

So a, a slug, b, a millipede, c, a lady bird, or d, an octopus?

Pause here while you decide.

Well done if you selected a and d.

The slug and the octopus have hydrostatic skeletons.

Some animals can be difficult to classify into the vertebrate or invertebrate group because of the way they look.

Here's Izzy, "These animals both have hard shells on their backs.

I think they're both invertebrates with exoskeletons.

" Hmm, interesting looking at that tortoise and crab.

And Jacob, "The tortoise is a reptile, which is a vertebrate, so I think the crab is too.

Its hard shell is its backbone.

" What do you think?

Pause here and share with someone.

The crab's shell is part of its exoskeleton.

It has no internal skeleton.

It is an invertebrate.

Whereas the torts is a reptile.

It has a spine and an internal skeleton, so it is a vertebrate.

Aisha and Laura are wondering about the earthworm and a snake.

Here's Aisha, "These animals are both very bendy and neither of them has arms or legs.

I think they both have bodies filled with fluid rather than an internal skeleton.

" And Laura, "I know the snake is a reptile, so it must be a vertebrate.

I think they're both vertebrates.

" What do you think?

Pause here and share with someone.

Thanks for sharing.

The snake is a reptile.

It has a spine and an internal skeleton, so it is a vertebrate.

There, we can see the snake skeleton.

What an amazing image.

The earthworm has no internal skeleton, so it is an invertebrate.

Perhaps these are the answers you came up with.

Let's have a check for understanding.

Which of these animals are vertebrates?

a, garden snail, b, horseshoe crab, c, adder.

Pause here while you decide.

Well done if you selected c, the adder.

And now, it's time for your first task.

Sam has classified some animals into vertebrates and invertebrates, but she has made some mistakes.

Number one, spot her mistakes, and two, explain why she might have made each mistake.

So, Sam has put in the vertebrates category turtle, shark, and lobster, and she says that the invertebrates are eel, worm, and spider.

Pause here while you have a go at this task of spotting her mistakes and explaining why she might have made each mistake.

I'll see you when you're finished.

It's good to be back with you.

How did you get on with that task?

Let's take a look at this response.

The lobster should be with the invertebrates because it has no spine or internal skeleton.

Sam might have thought its hard covering is a backbone, but it is an exoskeleton.

The eel should be with the vertebrates because it is a fish, so it's a vertebrate with a spine.

Sam might have thought it was an invertebrate because it is very bendy and flexible like a worm.

Well done if you had answers like these.

And now, we're onto our next learning cycle, groups within vertebrates and invertebrates.

Vertebrate animals can be further divided into groups.

"Can you remember any of the vertebrate groups?

" Asks Lucas.

Pause here and share with someone if you can.

Thanks for sharing.

Let's find out more about which animals are in which groups.

All of these animals belong to the same group except one.

Can you spot which one?

We have chaffinch, bat, penguin, and kingfisher.

Pause here while you spot which one does not belong in the same group as the others.

The bat doesn't belong in this group.

The rest of the animals are birds.

All of these animals belong to the same group except one.

Can you spot which one?

We have bat, shark, rhinoceros, and orca.

Pause here while you spot which one does not belong in this group.

The shark doesn't belong in this group.

The rest of the animals are mammals.

All of these animals belongs to the same group except one.

Can you spot which one?

We have a tang, shark, eel, and axolotl.

Pause here while you spot which one does not belong in this group.

The axolotl doesn't belong in this group.

The rest of these animals are fish.

All of these animals belong to the same group except one.

Can you spot which one?

We've got axolotl, newt, turtle, and frog.

Pause here while you decide.

The turtle doesn't belong in this group.

The rest of these animals are amphibians.

And all of these animals belong to the same group except one.

Can you spot which one?

We have the turtle, crocodile, chameleon, and armadillo.

Pause here while you decide who's in the wrong group.

The armadillo doesn't belong in this group.

The rest of these animals are reptiles.

Let's have a check for understanding.

Which vertebrate group do these animals belong to?

We've got the rabbit, lizard, toad, swan, and salmon.

We say it while you decide which group each of these animals belongs to.

Well done if you said the rabbit was a mammal, the lizard is a reptile, the toad is an amphibian, the swan is a bird, and a salmon is a fish.

Invertebrates can also be classified into further groups, including insects, arachnids, crustaceans, and mollusks.

Here, we can see a range of invertebrates.

Love those amazing colors and markings.

Insects have six legs, a body divided into three segments, and a pair of antennae.

And some common insects are beetles, bees, butterflies, and ants.

Arachnids have eight legs and a body divided into two sections.

Some common arachnids are spiders, harvestmen, scorpions, and ticks.

Crustacean have a hard exoskeleton and two pairs of antennae.

Some common crustacean include crabs, lobsters, shrimp, and barnacles.

And mollusks have a very soft body.

They have hydrostatic skeletons.

Some also have shells.

Some common mollusks include slugs, snails, squid, and octopuses.

Let's have a check for understanding.

Complete the sentences using the correct groups.

The groups are insects, arachnids, crustaceans, and mollusks.

And the sentences are, have two pairs of antennae and a hard exoskeleton, have a body in two sections and eight legs, have a very soft body and some have shells, have six legs and a body divided into three sections.

Pause here While you complete the sentences using the correct groups.

Let's take a look at the answers.

Crustaceans have two pairs of antennae and a hard exoskeleton.

Arachnids have a body in two sections and eight legs.

Mollusks have a very soft body and some have shells.

And insects have six legs and a body divided into three sections.

Well done if you completed the sentences in this way.

We can use classification keys to help us identify unfamiliar animals.

Classifications keys have a series of yes/no questions about the observable characteristics of living things.

Each question leads you to a new question until you identify the living thing.

So, here, we start with the question, does it have wings?

There's always just two options to the answer, either a yes or no.

If the answer is yes, we have another question.

Does it have feathers?

Again, yes or no.

If the answer is yes, we know it's a robin.

If the answer is no, it's a butterfly.

And let's go down the no route from the first question.

Does it have wings?

No, then we ask another question.

Does it have a shell?

Yes, then it's a snail.

No, then it's a slug.

This is a classification key.

Let's have a check for understanding.

Which of these questions could not be used on a classification key?

a, does it have feathers?

b, how many legs does it have?

c, can it breathe underwater?

d, does it have sharp claws?

e, is it furry?

Pause here while you decide.

Well done if you selected answer b, how many legs does it have?

This is not a question with a yes/no answer.

Classification key questions must always be answered with either a yes or a no.

And now it's time for your next task.

Use the classification key to identify the invertebrates.

Here are the images.

Pause here while you have a go at this task of using the classification key you've been given to identify the invertebrates.

So, how did you get on with that task?

Perhaps you answered the first question in this way, does the animal have legs?

And if you said yes, then maybe you'd ask again, does the animal have antennae?

If the answer was yes, perhaps you asked another question, is the animal green?

The answer was yes.

It's a praying mantis, an insect.

If the answer is no, it's a woodlouse, a crustacean.

If your answer to "Does the animal have antennae?

" was no, then it's a wasp spider, an arachnid.

And your first question, does the animal have legs?

If the answer was no, the next question was, does the animal have a spotty pattern on its skin?

If the answer is yes, it's a sea snail, a mollusk.

If the answer is no, it's a cuttlefish, a mollusk.

And here they are.

Well done for having a go at this task.

And now onto our final learning cycle, creating classification keys.

We can use our knowledge of similarities and differences between animals to create classification keys.

Sofia has five invertebrates that she found in school grounds and would like to create a classification key to help other children identify them and learn more about invertebrate groups.

Here are are Sofia's invertebrates.

Pause here and share with someone.

Have you seen any invertebrates like this in your local area?

Thanks for sharing.

What are the observable characteristics of the animal Sofia has found?

Pause here and share with someone.

The observable characteristics of the bee, spider, snail and, and slug.

Thanks for sharing.

We can use these observable characteristics to create a classification key.

To create a classification key, first we need to ask a yes/no question that will divide these animals into two groups based on their observable characteristics.

Does the animal have legs?

It's a good place to start, and the answer is either yes or no.

Pause here while you answer this question and decide which of these animals have legs and which do not.

Let's take a look at the answer.

The bee has legs.

The spider has legs.

The snail does not have legs.

The ant has legs.

And the slug does not have legs.

Sofia still has more than one animal at the end of each branch of her key, so she asks another question to divide the group on the no branch.

Does the animal have a shell?

Yes or no?

Pause here while you decide how to answer this question for the snail and the slug.

Perhaps you answered like this.

The snail has a shell.

The slug does not have a shell.

Sofia continues asking questions until she has only one animal left at the end of each branch, so she asks another question, does the animal have wings?

The bee does have wings.

The spider doesn't have wings.

The ant does not have wings.

And now, because we still have two animals on one of the branches, we'll ask another question.

Is the body divided into two sections?

Yes, this spider's body is, and no, the ant's body is not.

So, here is Sofia's classification key with the four questions that she asked to identify each of these animals.

Let's have a check for understanding.

Which question could we use to divide these animals into two groups?

a, does it have four legs?

b, can it walk?

c, is it a vertebrate?

Or d, how does it find food?

Pause here while you decide.

Well done if you selected answer a, does it have four legs?

Which question could we use for the last branch of this classification key?

a, does it have two legs?

b, how many wings does it have?

c, does it have an internal skeleton?

Or d, does it have feathers?

Pause here while you decide.

Well done if you selected answer d, does it have feathers?

This will help us to identify the human and the chicken, as one has feathers and one does not.

And now, we're onto our final task.

Choose four to six of these animals and create a classification key to help others identify them.

We have the red ghost crab, an octopus, scorpion, red admiral, tang, kingfisher, python, and poison dart frog.

Pause here while you have a go at this task of creating a classification key to help others identify four to six of these animals.

I'll see you when you're finished.

It's great to be back with you.

Here's Alex and his classification key, and he's asking, "Is it similar to yours?

" He started by asking, does the animal have wings?

Yes.

Does the animal have antennae?

Yes.

Then it's a red admiral butterfly.

No, then it's a kingfisher.

With that first question, does the animal have wings?

If the answer was no, Alex asked, does the animal have an exoskeleton?

Yes, then it's a red ghost crab.

No, then it's an octopus.

Great classification key, Alex, and I hope you enjoyed creating yours as well.

In our lesson, How and why we group animals, we've covered the following.

Scientists classify animals to make it easier to identify, name, and learn about them.

Animals can be classified by looking at similarities and differences in their observable characteristics.

Animals can be divided into vertebrates and invertebrates, then grouped again within these categories.

We can create classification keys for animals by asking a series of yes/no questions about their observable characteristics.

Well done, everyone, for joining in with this lesson.

It was great to get into classification, observable characteristics, and creating your own classification keys.

I really enjoyed teaching you, and I hope you enjoyed this lesson too.

I look forward to seeing you again soon.

And until then, stay curious.