Hi, everyone.

My name is Ms. Panchal and I'm really excited you decided to join me in our science lesson.

So our lesson today is going to be focusing on dangers to food chains.

And so, this is part of our bigger units of learning all about food chains.

So we're going to be using lots of different examples to help us understand our learning today.

Let's get started with the lesson.

So the outcome for our lesson today is, I can describe the impact on food chains when humans cause habitats to change.

So on the screen here, we've got a series of different keywords that we're going to use in our lesson today.

So we've got danger, extinct, habitat, and impact.

So what I'd like you to do is pause the video here and first of all I'd like you to read out the definitions to yourself and then I'd like you to read out the definitions to your partner.

Once you've done that, I'd like you to click play and we'll start the lesson.

Brilliant work, everybody.

Well done.

So I lesson today is split up into two parts.

So the first part of our lesson, we're going to be thinking about animals and plants in danger.

And then the second part of our lesson, we're going to be focusing on changing habitats.

So Jacob has read online that some plants and animals in different food chains are in danger.

What does this mean if it says that the animals in different food chains are in danger? What do we think this means? Have a think with your talk partner.

Brilliant.

So Jacob says, "The website reported that between 1960 and 1995, the numbers of black rhinos dropped from around 100,000 to less than 2,500." So a huge drop in number of black rhinos.

A type of plant or animal is endangered if it is at risk of being extinct.

Jacob says, "I read on the website that the lady's slipper orchid was thought to be extinct in the UK until one single plant was discovered in 1930 in the Yorkshire Dales.

Do you know what extinct means? So you said there that they thought this lady's slipper orchid was extinct, but actually they found one single plant in 1930.

What does the word extinct mean? Maybe you can share your ideas with your partner.

Brilliant work, everybody.

So when a particular type of a plant or animal becomes extinct, this means there are no living ones left anywhere on earth.

So extinct means there's not any of those living things left on the earth.

Laura says, "Do you know why some plants and animals are becoming endangered or extinct?" So pause the video here and I'd like to have a little bit of thinking time on your own.

Why do we think some plants and animals are becoming endangered or extinct? So Jacob says, "I heard on the news that there are lots of different reasons, but one is that humans are making changes to the habitats of living things and this is causing problems." Let's do a check of our learning.

True or false? Some animals and plants in different food chains are in danger.

Do we think that's true or false? What do you think? Brilliant.

The answer is true.

So we do know, and we've learned so far in our lesson today, that different food chains and some animals and plants in food chains are actually in danger.

Let's do another check of our learning.

If a plant or animal becomes extinct, this means a, there are very few of them left, b, there are none of them left, and C, there are lots of them left.

Which one do we think is correct? Brilliant.

The answer is b.

So if an animal or plant becomes extinct, it means there are none of them left on the whole planet.

Let's move on.

Izzy wonders if any plants or animals in the food chains in her garden habitat are in danger? So we've got a dandelion plant, caterpillar, blackbird and a cat.

Izzy said, "I don't think any of these plants or animals are in danger.

They look perfectly safe living in my garden and there are plenty of them across the UK and around the world.

So they are definitely not endangered like the black rhinos." Izzy's mum is also outside in the garden.

And Izzy's mum says this garden is very untidy.

I will make some changes as that it looks neater.

So we can see an image here of the garden.

It does look quite messy.

So Izzy's mum wants to tidy it a little bit.

So first, Izzy's mom mows the lawn to make the grass shorter.

Next, she removes weeds including dandelion plants along the path.

Izzy's mom also arranges for a local company to come and cut down the trees at the bottom of the garden.

So Izzy's mom has done a lot of things here to try and tidy up the garden.

A couple of days later, Izzy is out in the garden again looking for the food chain she recorded.

Izzy says, "The dandelion plants have gone and I could only spot one caterpillar.

Also, there aren't many birds out here today and I don't know why." Do you have any ideas? So pause the video here and have a think about what Izzy's garden looks like now.

There aren't many birds out and that Izzy is not really sure why? Do you know why there's not many birds out? Have a little think.

Great ideas, everybody.

Well done.

Let's do a check of our learning.

Which of these could affect the food chain of plants and animals living in a garden habitat? A, removing weeds, b, cutting down trees or c, None of these will affect the food chain.

Which of these is correct? Brilliant.

So actually there's two answers here.

So removing weeds and cutting down trees could affect the food chain of plants and animals living in the garden habitats.

So let's go on to the first task of our lesson today.

So I would like you to tell a partner why you think Izzy can no longer find as many caterpillars or birds in her garden.

Izzy says, 'There aren't many birds out here today and I can only spot one caterpillar." So what I'd like you to do is pause the video here and if you need to, go back over the last few slides to look at what Izzy's garden used to look like compared to what it looks like now.

And I'd like you to tell your partner or you can write it down as to why you think Izzy can no longer find as many caterpillars or birds in her garden.

Think really carefully about all you know about food chains.

Have a go at the task.

Click play when you're ready to continue and we'll go through some example answers.

Off you go.

Brilliant ideas, everybody.

Well done.

I'm so impressed with all of your ideas and I can see you've worked really hard to think about why Izzy can no longer find any caterpillars or birds in her garden.

So if we first focus on caterpillars, here is an example answer.

Izzy's mom has changed the habitat of the plants and animals living in her garden.

Many small animals including caterpillars shelter in long grass but now mum has mowed it.

They may have a much greater chance of being eaten by predators.

Also less grass and the removal of the dandelion plants and other weeds means there will be less food for the caterpillars and some caterpillars may have died and some may have had to go elsewhere to find food.

So this is a reason why Izzy may not be able to find many caterpillars in her garden anymore.

Did you get a similar answer about caterpillars? Well done for having a good go everybody.

So let's move on to why Izzy couldn't find many birds in her garden.

So Izzy's mum has changed the habitat of the plants and animals living in her garden, and there are fewer caterpillars for the birds to eat.

So some birds may have gone elsewhere to find food to survive.

Also, the trees in the garden have been cut down, may have had birds nests in them, so the birds will have to find another place to live and will no longer live in the garden.

So cutting down those large trees at the back of the garden has had quite a big impact and the fact that there's not many birds in Izzy's garden anymore.

Did you get the similar answer? Well done for having a fantastic go, everybody.

I'm so impressed with your work so far.

So we finished the first part of the lesson where we focused on animals and plants in danger and we're now going to think about changing habitats.

So humans can cause the habitats of plants and animals to change.

This can have a negative impact on the food chain.

Izzy says, when my mum had those trees cut down to make our garden look tidier, she removed the habitats of some living things that depend on the trees to shelter and survive.

There are lots of other reasons why humans chop down trees.

Do you know why? So pause the video here and I'd like you to work with your talk partner and write down some ideas of why some humans chop down trees.

What are the different reasons? Once you've written down a few ideas, click play and we'll go through some examples.

Excellent discussion, everybody.

And I can see you've jotted down lots of different ideas on your whiteboards, which are super so well done.

So humans change habitats by cutting down trees to make space for crops to grow or for animals to graze.

In addition to that, they also use the wood as building materials for to make furniture, but lots of other items as well because lots of items in our homes, for example, can be made out of wood.

Let's move on.

So this food chain can be found in a tropical rainforest habitat.

So we've got tree, caterpillar, chimpanzee and leopard.

What could happen to these animals if humans cause their habitat to change by cutting down trees? So pause the video here and look really closely at the food chain here.

So what do we think would happen to these different animals, the caterpillar, the chimpanzee, and the leopard if humans were cutting down trees? What do we think would happen? Pause the video, have a think with your talk partner and have a discussion.

Once you've had a chance to have a chat about it, click play and we'll continue with the lesson.

Brilliant discussion, everybody.

Well done.

So Izzy says, "When humans cut down trees, this has an impact on caterpillars that depend on food from trees.

So this could reduce their population size because the caterpillars won't have as much food to eat as there is less food for the chimpanzee.

A small change to a habitat can have a large impact on the whole food chain." There will be less food for the caterpillars to eat, which means their caterpillars won't survive as long, which means the chimpanzees won't have as much food.

So it is really important to understand that one change in a food chain can actually have a huge impact on all of the other things that are involved within that food chain.

Let's do a check of our learning.

Who do you agree with? Izzy says, "When humans cut down trees, they are only causing the habitats of plants to change." But Jacob says, "When humans cut down trees, they are causing the habitats of both plants and animals to change." Who do you agree with? Which one do you think is correct, Izzy or Jacob? Have a little think.

Brilliant.

So, Jacob is actually correct.

So when humans cut down trees, they're causing habitats of plants and animals to change.

Brilliant work, everybody.

Well done.

Let's move on, shall we? So humans can cause habitats to change in other ways.

Hunting is when humans look for and kill wild animals for different purposes.

For example, elephants are hunted for their tusks, ducks or geese can be hunted for sport and trouts and salmon are hunted to be used as food.

So there are other ways in which humans can cause habitats to change.

Laura and Lucas have been finding out about different food chains that are affected when animals are hunted by humans.

So in this food chain we've got raspberry, mouse, weasel and fox.

Laura says, if the fox is hunted by humans, then there will be no impact on the rest of the food chain.

Do you agree with Laura? So pause the video here, have a look at the food chain again.

And Laura is saying, if the fox is hunted by humans, then there will be no impacts on the rest of the food chain.

What do you think? Have a think with your talk partner.

Interesting ideas, everybody wells on for having a good go.

So when habitats change, the number of plants and animals living there may also change.

So let's do a recap of this food chain example.

So we've got a raspberry plant, mouse, weasel, and fox.

So if there are fewer foxes due to hunting, this might lead to an increase in the weasel population because fewer are eaten as food for the fox.

So there's more foxes being hunted, there's actually gonna be more weasels because there's gonna be less foxes that are going to eat them.

If there are more weasels, then they will need more food so this would impact on the mouse population.

And if more mice are eaten, there will be fewer mice to eat the raspberry fruits and this could lead to an increase in raspberry plants in this habitat.

Let's do a check of our learning.

When habitats change, a, the number of plants living there may change, b, the number of animals living there may change, or C, there will be no changes to the number of plants and animals living there.

Which answer do we think is correct? a, b or c? Super.

The answer is a and b.

So when habitats change, the number of plants living there may change, but also the of animals living there may change as well.

So it's important to remember that one small change in the habitat or one change in the food chain can actually have a huge impact.

Let's move on to the next task.

If rabbits are hunted by humans, what could the impact on this food chain be.

So here we've got grass, rabbit, stoat and cat.

So if rabbits are hunted by humans, what could be the impact on this food chain? So pause the video here and you might want to write down your answer or you can talk to your partner about it.

Alternatively, you can maybe record yourself or video yourself giving your explanation.

Pause here, have a go at the task, click play when you're ready to continue and we'll go through the answer.

Brilliant work everybody well done.

So if the number of rabbits is reduced because they are hunted by humans there could be less food for the stoat to eat.

So the number of STS might reduce or they may have to move to a new habitat to find more food.

If there are fewer stoats, then the cat may have to find different foods to eat, such as mice or birds, and this will affect other food chains With fewer rabbits eating grass, the grass may grow longer.

So by one change happening within the food chain actually impacts other living things within the food chain as well.

Did you get a similar answer to this? Well done for having a good go at this task, everybody.

Well done.

So we've come towards the end of our lesson now.

So let's do a summary of our learning.

So we know that some plants and animals in a food chain are in danger and humans can cause the habitats of plants and animals to change by cutting down trees or hunting.

And when habitats change, the number of plants and animals living there may also change.

So we've looked at various examples today of how one small change than a habitat can actually impact a whole food chain and it can impact the number of plants, but also animals in that habitat as well.

Now, I'm so impressed with all of your work today.

You've worked incredibly hard.

I hope you have a great rest of the day and I'm sure I'll see you really soon.

Bye-bye.