Lesson video

Our lesson question today is how are organisms adapted to hot environments? So in our last lesson, we learned what an adaptation is, and we actually had a go at making up our own creature or organism in an imaginary environment, but in today's lesson and in the next lessons, we're going to be looking at real life environments and the adaptations that we find there.

So today we're focusing on hot environments.

We are doing adaptations, and this is what you're going to need today.

You're going to need to please a piece of paper, a pencil, a colouring pencil, and a ruler.

So if you don't have any of those things, you can pause the video now and you can go and get them.

Fantastic.

These are our star words for today.

So I'm going to say the star word, and then you're going to repeat it back to me.

It can feel a bit funny doing that to a screen, but it's important that everybody watching this video and taking part in this lesson practises saying these words.

First of all, it helps them to stick in your memory.

And second of all, it means that you will pronounce them and say them correctly when you are impressing your friends and your teachers and your family with your awesome science knowledge and facts.

Okay.

So when I point to me, I'll say, when I point to the screen you're going to say.

Nocturnal, camouflage, adaptation, environment, conditions, organism.

Great, good job.

Let's talk about what some of these words mean before we start our lesson.

So an organism is a living thing, so it could be a plant or an animal and we're going to be, or it could be micro organisms, we're nor going to go into those today.

We're going to be looking specifically at plants and animals today, which are both a type of organism.

We're going to be looking at a particular environment.

And that's the surroundings in which an organism lives.

We're going to be looking at hot environment today and describing the conditions in those environments.

The conditions are kind of like the characteristics of the environment is how you would describe it.

So it could be the temperature, the amount of rainfall, the colour, those kinds of things.

Those are conditions of environments.

We're going to be looking at adaptations.

And actually I'm going to remind you of that definition in a moment.

We are going to be using a word we learned last lesson camouflage.

And that's where an organism blends into its surroundings.

And a new word for this week, nocturnal.

So we can describe an animal as being nocturnal.

And that means it's mostly active at night, as opposed to being mostly active in the day.

So something like a robin, a type of bird would not be nocturnal.

We call it diaconal, but they are active during the day.

Whereas something like a bat is nocturnal because it's active.

It's finding its food.

It's flying round it's awake at night time.

Op I've gone backwards.

This is what we're going to do in today's lesson.

We're going to start with a quick recap like we always do.

Then we are going to look at the conditions in desert environment.

Then we're going to look specifically at desert plants and their adaptations, and then desert animals and their adaptations.

So the first thing I want you to do is there are three pictures on the screen.

These are three organisms that we learned about last week.

I wonder if you can remember anything about these animals.

Can you even, or plants so.

Can you remember what they're called? Maybe one fact about them.

Challenge yourself to write down anything you can remember.

I'm going to give you, oh, just 45 seconds just a quick recap off you go.

Going to sip my coffee while you do that.

If you need a hint for the plant, it is really smelling.

It smelled like something in particular.

Okay 10 seconds left.

Can you remember anything else? Okay, well done if you were able to remember anything about those animals.

So the frog on the right was our Alaskan wood frog that could freeze its whole body and become a little frog like icicle in the winter.

And the flower in the middle was called a corpse flower, that smells of corpses.

It smells of dead bodies, which is pretty gross.

It's also a huge, it can be two metres tall.

And the reason it smells is to attract things like dung beetles, that help to pollinate it.

And then we have our kangaroo rat, which is the little fairy thing.

And that's actually an animal we're going to be learning a little bit more about today, but we learned that this kangaroo rat can jump really high in order to get away from predators.

Well done if you remember anything about those organisms. Can you remember our definition of an adaptation? So we've got a polar bear hair with some examples of adaptations, white fur, thick fur, can swim, sharp teeth and claws, can you remember what our definition was? If you can say it to your screen and adaptation is.

So an adaptation is the characteristic of an organism that helps it to survive.

Okay.

Say it with me so that it sticks in our head.

An adaptation is the characteristic of an organism that helps it to survive.

Great.

Okay.

The key thing there is that it helps it to survive.

So it's different from just a normal characteristic like my blonde hair is a characteristic.

It doesn't really help me to survive.

So here's a lion.

Here are four of its characteristics, which one is the odd one out, which one is not an adaptation and doesn't help it to survive? Say it to a screen.

Great.

Soft ears is the odd one out.

It's a characteristic that lioness does look like she has very soft ears, but they're not going to help her to survive.

Well done.

Now let's apply what we learned last lesson and went over in that recap to a new environment.

We are going to be looking at deserts today.

This map shows you where we can find desert environments in the world.

So you can see the desert environments are coloured in red.

They're mostly found in the centre.

So a big strip through the middle where the equator would be.

That's the hottest part of the earth and that's where we find deserts.

But it doesn't so not just hot, they are also dry.

So we don't find them everywhere.

Here is a picture of a lovely desert environment.

What do you think it would be like to be an animal or yourself in this environment? What were the conditions be like? You did have a brief look at this last lesson.

How would you describe this environment? How is it different from my living room? Can you just jot some notes down for me now please, pause the video to do that.

Great.

So you might have written things like hot, dry, sandy.

There's not very many plants, so you might even have written empty or barren.

And we did speak last week, how the colour of the environment is quite an important condition.

And we know that because lots of animals are camouflaged to be the same colour as their environment.

So you might have written a kind of sandy colour as well, or like a yellowy browny, orangy I'm not sure which one you might have gone for.

Okay.

All of those are correct.

We're going to learn some more specific conditions as well today.

So in a dessert we often think of deserts as being really hot places and they are really hot.

If you think about the average kind of weather in England, the temperature can range from, I mean, in winter we might get to minus and we might get to like minus three, minus two.

But I say our average is about kind of 15 degrees.

In summer we get a bit warmer we get to about 27, 28 sometimes maybe if we're getting a heat wave, we might up to 30.

But that's kind of the range of our environment that we're used to here in the UK.

If you compare that to a desert there summer daytime temperature gets all the way up to 40 degrees.

So that's really hot.

And we do often think of deserts as being really hot environments.

However something you might not know about desert is that at night time, they drop to below zero degrees.

So they are really, really cold at night time, which is a bit crazy.

Because if you think about the UK, we get kind of this cold in winter and this warm in summer, but in just one day in the desert, it gets this hot during the day and it goes below zero.

So this cold at night time.

So in just one day, they're hotter than our hottest day in summer.

And they as cold as if not colder than our coldest days in winter.

So we call that the range, the range in a dessert of temperature is really big.

So that you imagine that you are in the desert.

So maybe you're stranded that you're stuck in this desert.

What's going to be tricky about surviving there.

What are you going to bring with you? Well, in the daytime, you're going to be want to be wearing clothes that keep you really cool and cover you from the sun.

But then what about at nighttime? It's not going to help at night, at night you're going to be freezing.

You're going to need lots and lots of layers and you're going to have to be wrapped up really warm.

So it'd be really hard to survive in a desert.

So I want you to bear that in mind, we're thinking about our animals and our plants that live here.

They've got a really tough job.

There's something else.

That's a really important condition of desert.

So we do often think of them as being very hot, but we've learned already that that's slightly inaccurate because they're also really, really cold.

Perhaps the most important condition of a desert is that it's very, very dry.

So in a desert, you get less than 250 millimetres of rainfall a year.

So that's not very much, if you think about the normal kind of 30 centimetre ruler that you would have in class, that's 13 millimetres.

Sorry, that's 300 millimetres.

So a little bit less than that.

That's how much rainfall falls in a desert in an entire year.

So if we imagine again, that we've been dropped in a desert and we need to survive, or if we imagine we're a desert animal and plant, we're going to have a big problem there.

There's not very much rainfall.

That means there's not big sources of water lying around.

There's not a lot to drink.

If you think about how much humans need to drink a day, it's about two litres.

It's about the size of this bottle.

That's how much water we need to drink a day.

So if we're only having, that much rainfall over a year it's going to be very hard to find the water that we need in a desert.

So that's another thing that we need to bear in mind when we're thinking about animals and plants that managed to survive in these conditions.

There's something else that I want to point out before we move on.

So we often think of deserts as being really hot, but actually the most important feature of deserts is the amount of rainfall they get.

The fact that they're really dry.

And a fact that I learned that kind of made this really obvious to me and kind of prove this point to me was that Antarctica where the penguins live could actually be classed as a desert, which seems mad because it's freezing, it's very cold.

So why do you think it could be class categorised as a desert? Because it's so dry.

In Antarctica, it hardly ever rains.

If precipitation does fall it's normally a snow, it's not as water and they get as little as 50 millimetres of rain a year.

So it's about that much.

So Antarctica is actually incredibly dry as well.

Okay.

So although deserts do get really hot during the day up to 40 degrees C, they also get really cold below zero at night.

The most important condition that you find in the desert is that lack of water they're so dry, less than 250 millimetres of water a year.

Let's see how much you can remember from that explanation.

Could you please copy these sentences down and fill in the gaps.

Have a go, see what you can remember if you're getting really stuck, then you could always go back and watch that part of the video again.

Pause the video and complete the task for me now please.

Great.

Let's see how good your memories are this morning or this afternoon or whenever you're watching this video.

Daytime temperatures can exceed 40 degrees C.

At night temperatures can drop below zero degrees C and does it scale less than 250 millimetres of rainfall a year? Well done.

If you've got those correct give yourself a tick.

If you didn't, that's fine just correct your answers next time.

I bet you remember them.

Let's have a look now at some plants that we find in the desert.

I wonder if you can predict the picture, I'm going to show you next.

When you think of desert plants or plants really hot environments, what's the first thing that comes to your mind? Have a think for me, see if you can close your eyes and picture it.

Was it a cactus? So here is a picture of a cactus and this is the kind of plot that you would find in the desert.

We actually call these what they are, these I have shown you cactus, but this kind of family of plants are called succulents.

What are they called? Succulents.

And that's because they have lots of water stored inside them.

If you were to break them open, they would be like quite juicy almost.

So you wouldn't buy into a cactus cause you get spikes in your tongue.

But if you were to, it would be quite juicy and succulent.

So we actually call them succulents.

And we're going to look now at some different ways that these plants have learned to survive in their desert environments.

So remember that the main thing that they have to survive is the fact that there's not a lot of water around.

Plants in the UK get rained on all the time.

So water and getting access to that water that they need is not so important for them.

But our desert plants, our cactus's and our succulents.

They have evolved some really clever adaptations to make sure that they can still survive in these really dry environments.

So the first adaptation is they have water storage within the plant.

So when I said you could kind of break it open and it would be quite juicy that's because they're storing water inside them.

They can store it in their stems, in their leaves, in their roots or even in fruit.

So they store that water for times when they need it.

They also have a really waxy skin.

So their skin is very smooth and shiny a bit like a crayon.

It's also very thick.

And the reason for that is that they lose less water from their leaves.

So you can think of it as a bit like a waxy waterproof coat.

They also have spines.

So those are the kind of characteristics spiky bits like cactus.

And those are important for two reasons.

The first is that it stops animals from eating them.

So if I was an animal living in a desert and I couldn't find water anywhere then and I know that practises store water inside them, then I would think to myself, right? Well, I'm going to take a big bite out of that juicy cactus to get my water.

But the capsules have an adaptation to protect against that.

They have these spines so that animals can't or find it much harder to come and eat them for their water.

So spines protects the plant, but they also stop water from evaporating or escaping from the plant as well.

Because if you have a big, long flat leaf like this, then there's lots of surface for the water to evaporate from.

If you have a skinny little spine like this in the surface that the water can evaporate from is much smaller.

And the last thing they have is they have something called tap roots.

My term tap roots.

Tap roots are basically just really long roots.

They can be up to seven to 10 metres long.

So that would be as long as like five of me lying down next to each other.

Those are really, really long roots.

And the reason for that is so that they can reach deep under the ground to access water supplies and then much, much longer and bigger than the plant that's visible at the surface.

So you might have a small little kind of cactus sitting on the top and then its roots could be as much as like 10 times the size of the plant itself.

They have to travel really far to search for that water.

So we've got full main adaptations of our desert plants here.

Let's go through and can you say them with me? So we're going to start with waxy skin just to help them stay in our brain.

So number one, waxy skin, number two, spines, number three, water storage and number four, tap roots.

Great.

Let's see what you can remember.

I have here on the screen, three of our four adaptations, so waxy skin, spines and tap roots, and then next to them, there's a description.

Can you match up the description to the adaptation? So what does waxy skin do? Does it reach deep into the ground? Does it reduce water loss? Or does it prevent animals from eating the plant? You could write a full sentence for this, or you could just write waxy skin and then the number that it matches.

So if I thought waxy skin was to prevent animals from eating the plant, I would just write waxy skin three.

Pause the video and complete this task for me now please.

Great.

Good job.

Let's check your answers.

So, tap roots matched up with number one.

Tap roots reach deep under the ground to access water supplies.

Waxy skin matched up with number two.

Waxy skin is there to reduce water loss like our waxy waterproof coat.

And spines matches up with number three to prevent animals from eating the plant.

Well done if you've got those correct.

Give yourself a big tick.

If not, no problem just correct your answers for me before you move on, you can pause the video if you need more time.

Okay.

My next task for you is can you please draw a picture of a cactus? And can you remember to add labels to it please? So there are four adaptations that you are going to label on your cactus.

Can you pause the video to label those now.

To draw and label you can use colours if you want to as well.

Fantastic.

I'm just going to flick back so you can check that you have all of the full correct labels on your cactus.

Did it look something like this? Don't worry if you drew a different style cactus, that's absolutely fine, but I would like you to double check that you have all four of these labels, waxy skin, spines, water storage, and tap roots.

Pause the video just to make sure you've got all of those four for me now please.

Fantastic.

Okay.

Let's move on to the part of our lesson where we're going to look at desert animals.

What animal is that say it to your screen? It's a camel.

Okay.

So we're going to look at two different types, actually that's not true, I just told you a lie there I'm sorry.

We're going to look at three different types of desert animals.

We're going to start with the camel.

What are the challenges for this camel living in this environment? Can you remember? There'd be the same challenges for us if we were living in this environment.

It's very hot during the day, but it's very cold at night and there's not much water.

So what I would suggest you do before we start please is I'd like you now to pause the video and draw a picture of this camel.

And I want you to leave some space around the picture so that while I'm explaining the camel's adaptations, you can add some labels and some explanations to each one.

So you can add some notes around your camel.

Well, I would say before you start, is that remember that this is a science lesson, not an art lesson.

So if you really love drawing and you're really good at drawing, then that's fantastic.

You get an opportunity to draw a beautiful picture of a camel here and have a lot of fun doing that.

If, maybe drawing isn't your favourite thing to do, or you don't think you're very good at drawing, doesn't matter.

Okay.

If I'm being honest with you, I'm not very good at drawing.

It's definitely something I'd like to practise and get better at, but I don't let it stop me when I'm doing science.

Okay.

Scientific drawings should be quite simple.

Anyway, you just need to show a rough outline of what it is that you're drawing and all your labels will make it really clear what you're drawing.

So pause the video now please and draw a rough picture of a camel, or if you'd like to, you can spend a bit longer and make it really beautiful and elaborate to you.

Pause the video and do that for me now please.

Great.

Okay.

So I'm going to tell you some of the different adaptations that a camel has.

And while I'm explaining, you're going to make some notes.

If there's any point where I'm going a bit too fast for you to write, then you can just pause the video and go back and listen to that bit again.

It will try to be slow there.

So camels the first adaptation is that they have really long eyelashes.

They have really hairy ears and they can close their nostrils.

So we can't close our nostrils.

We always have our nostrils open, but they can actually close theirs like this so there's no hole.

And the reason for all of those three things, the hairy ears, the closing of the nostrils and the long eyelashes is to keep sand out.

So we know that deserts are covered in sand and sometimes it's really windy and there are sand storms and the sand blows all around.

So the camel needs to make sure that that's sand isn't going up its nose, it staying out of its eyelashes and it staying out of it's ears.

The next thing it has is it has really thick eyebrows, which actually stand out from its head.

So they protrude like this way and that's to shade his eyes from the sun.

So you can see when I put my hand over my eyes like this, you can see a shadow goes over my eyes.

So if my forehead and my eyebrows stuck out that much, my eyes would be shaded from the sun and a camel's forehead and eyebrows stick out to shade it's eyes from the sun.

So by now we should have long eyelashes, hairy ears, and kind of saying it nostrils and thick eyebrows labelled on our camel.

Pause if you need to catch up.

They also have really wide feet.

Now that's also important because of the sands that they're living on.

If you were or if you have really pointy feet or you're wearing something like a pointy high hill on ground that's really soft then that point is going to sink into it.

So if you're on mud or you're on sand and you're on a point it will sink in.

So if you've ever worn a pair of high heels on soft ground, you might've experienced that.

If you've ever worn a pair of like football studs, those little studs are quite thin and they often stick into the grass.

Okay.

However, if you have a really flat wide surface, it doesn't sink into those soft materials.

So that's why the camels have really wide feet.

So label wide feet on your diagram.

Okay.

I want you to be really honest now, and I'm going to be honest too, until I think I was an adult.

I always thought that camels stored water in that hump on their back.

Did anybody else think that? If you thought camels stored water in their hump, can you be really honest and tell your screen and say, "I thought Camels stored water in that hump." They don't.

And this really surprised me when I learned this, because like I say, until I was an adult, that's what I thought.

But actually camels do not store water in their humps.

They can go a really, really long time without drinking any water and they can drink gallons of water in one go when they do find it, but they don't store it in the hump.

In fact, what they do have in that hump is fat.

So that pump is just filled of fat.

And that means that they can go months without food as well, because that's like an energy storage in their back.

And they can break down that fat, which is like a substitute for their food.

Okay.

So you can add a label to the hump that says stores fat, and then somewhere else on your camel, you can just add a label that says, can go without water for a week.

The reason that some animals can live in the desert and go without water for a much longer time than us.

That is an adaptation it's mostly to do with the organs in their body.

And the organs in their body look quite different to our human ones.

So often their kidneys, which are the organs in our body that produce our urine.

And help us to process water look quite different, but we're not going to go into that into too much detail.

It's enough to note that they can go a really long time without having to drink water.

Another reason why they can go so long without needing so much water is that camels can stop themselves from sweating.

So if you've ever been running around on the playground really hard or working really hard in your PE or your sports, then you'll know that when humans get really hot and or they're doing lots of exercise, they sweat, water comes out of their skin.

If we were in a desert that would be quite a big problem because we'd be losing water really fast.

So camels can stop themselves from sweating.

So they don't lose water like that, which is really important in the dry desert.

So you can add a label to a diagram that says don't sweat.

Camels are also really well camouflaged.

Why are they well camouflaged? Because they're the same colour as their surroundings.

You can see from this picture they're a sandy colour.

And lastly, they have really thick fur that helps to keep them warm at night.

So that is quite confusing about desert animals.

They actually often have very thick fur, because although it's hot in the day, they need to be kept warm at night.

And in the day they have other things to keep them cool like trying or not moving very much.

Whereas in the night they need that thick fur to keep them warm.

Great.

So hopefully by now you have lots of annotations on your panel and you can see some of the adaptations that animals have in the desert.

Now, each animal is different.

So I'm going to show you an example of another animal, so you can kind of compare it to the camel.

Our next animal is our friend the kangaroo rat.

So we've already learned about the amazing jumpy abilities of the kangaroo rat, and that's helps it to get away from predators, but it's also got some pretty amazing adaptations that help it to live in the desert.

And these are quite similar to other small animals that you would find in the desert.

So, because water is so rare in the desert, most animals get their water from the food that they eat.

So this kangaroo rat is the same.

It eats plants and seeds in order to get its water.

The most kind of important adaptation of this animal is that it's a burrower.

It burrows that means it digs.

And it lives in those burrows, sorry, almost all of the time, unless it's coming out to find food.

This is important because those burrows don't get too hot or too cold and they have more dump air inside.

So if you imagine, if you're on the surface of the sand, then you're going to get all of the sun's rays and you're going to be really hot during the day.

And then at night, you're going to be really cold cause there's nothing around you to keep you warm.

And the wind will be able to blow past you.

But if you are able to dig yourself deep into that sand and build yourself a little burrow, then that would protect you from the sun during the day and getting too hot.

But it would also mean you stay warm at night because you have this kind of lovely bubble of warm humid air that you've up, keeping you warm.

Okay.

So that's how these animals live.

They live in these burrows and then they'll emerge at night to feed.

What did we call an animal that's active at night? If you know it say it to your screen, nocturnal.

Okay.

So these animals are nocturnal and they build burrows.

I've got an exercise for you to do now to see how much we've remembered.

So similar to the cactus one, I've given you five adaptations down the side that are common in desert animals.

So these are things that we find at the camel or the kangaroo rat or other animals that live in the desert.

And they are hairy ears, sandy colour, nocturnal, burrowing so that's our digging and thick fur.

Can you please match them up to the explanation of the adaptation on the side? So for example, sandy colour would match up with camouflages and reflects sunlight.

So you could either write that out as a sentence, or you could write a sandy colour one because that's the number of the description that it matches up with.

Can you pause the video please and complete the task now.

Fantastic.

Let's check your answers.

Say sandy colour matches up with number one.

It helps the animal to camouflage.

It also reflects the sunlight.

So if we think back to our lessons on light reflect means bounces off and that's important.

Dark colours absorb sunlight, and they get really hot.

So you might have left something dark coloured, something black out in the sun before, and then touched it you can feel that it gets really hot.

It absorbs whereas light coloured or whiteout it reflects it's much less likely to get hot.

So it's important that these animals have light coloured fur to reflect that sunlight.

They've got hairy ears is to keep out sand.

They've got thick fat to keep them warm at night that matches up with number three.

Number four, sorry, nocturnal matches up with number four, which means they're not active during the hot parts of the day.

And burrowing matches up with number five, which is when they create holes in the ground, which are humid and not too hot or cold.

Well done if you've got those correct.

Give yourself a big tick, if not, don't worry you can correct your answers and pause the video if you need more time to do that.

Fantastic.

I'm going to show you a picture now of our last desert animal.

This is very sweet looking fennec fox.

So I'm going to say it, and then you're going to say it fennec fox.

Great.

So now we've learned about two types of desert animal.

We've learned a kind of adaptations that they have.

I wonder if you could have a really close look at this fennec fox and have a guess an educated guess about what adaptations this fennec fox might have to living in the desert too.

So which parts of maybe which adaptations from the camel might it have, which adaptations from our kangaroo rat might have.

Can you pause the video and write some of your ideas down for me now please? Great.

So I'm going to show you a list now, so you can check your answers.

This is not all of the possible answers you might have come up with with some more things, but these are the main ones.

So fennec foxes are burrowers.

They're small animals that dig into the ground a bit like our kangaroo rat and that helps them to stay not too hot and not too cold.

They're also nocturnal.

They're mostly active during the night.

They have thick fur, which you could see from the picture and that keeps them warm at night.

And they have sandy coloured fur, or you might have written that they camouflage and that helps them to blend into their surroundings and to reflect the hot sunlight from their fur.

Well done if you manage to figure those out.

And I bet that as we work through this unit, you start looking at pictures of animals and thinking, I can tell where that animal would live because of the colour of its fur, or because it looks like this where it's got this adaptation so the more we learn about adaptations, the more we can make those kind of educated guesses and be detectives about where animals might come from and why and what they might have to survive in those places.

Well done for all of your hard work today.

Before we go and you do your post-lesson quiz, let's quickly recap and have a summary of our main star words and points from this lesson.

So we learned about two types of organisms today.

We learned about plants and animals that live in desert environments.

And we looked at some of those conditions in a desert environment 40 degree C during the day, below zero at night and only 250 millimetres of rainfall.

We looked at some of the adaptations that those organisms would need to survive in those conditions.

So for example, being nocturnal or camouflaging.

Okay.

So we've learned about lots this lesson.

In our next lesson, we'll be looking at the adaptations in a different type of environment.

If you would like to share your work, then you can ask your parent or carer to share photos of your work on Twitter with the #learnwithOak and #ONAscience, then I should be able to see your work.

And I do love seeing everybody's fantastic hard work.

You've worked so hard today that Charlie has appeared.

Charlie say hello.

He is a clever a boy.

Have a nice day, everybody.