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Hi, everyone.
I'm so pleased you've come to join me to learn some science today.
I'm Mrs. Horan and I'm really looking forward to learning all about endangered animals in today's lesson.
Today's lesson is part of the unit on reproduction and life cycles of animals.
This lesson is called Endangered Animals and Their Life Cycles, and we will be learning about how some animal life cycles are facing challenges, and this is leading to their numbers falling.
The outcome for our lesson today is to find out about why some animals are in danger and the impact this could have on their life cycles.
This lesson builds on what you already know about animal life cycles and is part of our big learning question: how do living things grow and reproduce? These are the keywords that we're going to be focusing on today.
Species, extinct, reproduce, endangered, and research.
You're probably familiar with some of these and less familiar with others.
We're going to look at each one in detail when we come to it in the lesson, so we'll have a really good understanding of them all by the time we finish.
And here are some explanations of the keywords.
Like I said, our new words are going to be explained when we get to them during the lesson, so you don't need to look closely at these now.
They're just here in case you need a reminder of something later on and want to look back to double check something.
In our lesson today, we have three parts.
Let's get started with the first part: Becoming Extinct.
Can you see the drawing of a bird on the screen? Do you recognise this animal? It is called a dodo.
I bet you've heard of dodos before.
Do you know anything about dodos? Have you ever seen one? Dodos are a species of bird that has become extinct.
Now you can see we've got two keywords in that sentence, so let's slow down for a moment to think about those.
The first keyword is species.
A species is a distinct type of living thing.
So tigers are a species, so are penguins, armadillos, crocodiles, lots of other types of animals.
We can also use the word species to talk about distinct types of plants, but for today we're focusing on animals.
Now let's think about the word extinct.
This means there are no living ones left anywhere on Earth.
When a species becomes extinct, it means it's completely gone and will never exist again.
This has happened to dodos.
Because there are none left, their life cycle cannot continue.
They are unable to reproduce and make more dodos.
We know that that word reproduce means to make more of something.
So there are no dodos left to make more dodos.
Their lifecycle has ended.
This means that there will never be living dodos ever again.
The story of the dodo is a really interesting one.
I've never seen a living dodo and you won't have done either because they became extinct at some point in the 17th century, long before any of us were born.
We don't even have any photographs of living dodos because they became extinct before cameras were invented.
The one you can see in the photo there is a preserved dodo, meaning scientists kept a dodo that had died and carried out some special processes on its body to preserve the outside of it, allowing us to see what they looked like.
Dodos used to live on an island called Mauritius where there were no predators.
Now, because they didn't need to worry about being eaten, dodos couldn't fly or even run.
They even lost their sense of fear about being eaten.
This was fine for a long time, but eventually humans from Europe came to settle on the island and brought with them dogs, cats, rats, and even monkeys.
These animals began eating the dodos and their eggs, which made it hard enough for them to survive, but as the humans also started cutting down the trees that gave the dodo shelter, they lost their homes and hiding places too, and it wasn't long before they had all died.
It's not just dodos though.
Lots of animals have become extinct over the history of our planet.
Do you know about any extinct animals other than dodos? You might wanna pause the video here to share your ideas with a partner or hear what they have to say.
Woolly mammoths and sabre-tooth tigers are some examples of species that have become extinct.
You can see fossilised skeletons of these animals here.
These animals also became extinct long before we were able to take photographs, so we don't know exactly what they look like.
Their extinction was even before a time when scientists were able to preserve animal bodies like they did with the dodo we saw.
So their fossils are the best thing we have to help us understand what they might have looked like.
We also know that dinosaurs became extinct.
There were loads of different types of dinosaurs and they roamed the Earth for millions of years before dying out.
But like woolly mammoths and sabre-tooth tigers, they became extinct before we had the technology to take photographs.
In fact, dinosaurs became extinct long before human beings even existed.
All of these animals that we have looked at became extinct a long time ago.
For the dodos, it was around 350 years ago.
Woolly mammoths became extinct around 4,000 years ago.
Sabre-tooth tigers disappeared around 9,000 years ago, and if you can believe it, dinosaurs became extinct, an incredible 65 million years ago.
Here's an interesting question, do you animals are still becoming extinct today? What makes you think so? You might want to pause the video here to have a discussion about this with someone before we find out later on in the lesson.
Let's have a quick check for understanding.
Which word means a species has disappeared and there will never be any more of its type again? Is it A, extinguished, B, extinct, or C, existence? Great.
It was B.
Extinct means a species has disappeared and there will never be any more of its type ever again.
Now you need to use the words in the box to fill in the blanks in these sentences.
You don't need to use all of the words, so think carefully about which one will be best in each sentence.
Sometimes all animals in one, die out.
If there are none of an animal left, then they cannot, to create more.
This animal has become.
And our words to fill in the gaps are: environment, extinct, habitat, offspring, reproduce, species, and survive.
Pause the video here to have a go at completing those gaps.
How did you do? Let's see how many you got correct.
Sometimes all animals in one species die out.
If there are none of an animal left, then they cannot reproduce to create more offspring.
This animal has become extinct.
Now it's time for you to put your learning into practise with a task.
Alex has written a report about animals becoming extinct.
Your job is to find and correct his mistakes.
Here is his work.
When an animal's lifecycle cannot continue the animal becomes extinguished.
This means most of the species will die out.
Dodos and dinosaurs are examples of animals that this has happened to.
One day these animals might be able to return to Earth and start reproducing again.
Pause the video here and see if you can find and correct all of Alex's mistakes.
Come back when you think you have spotted them all.
Let's see how you did.
When an animal's lifecycle cannot continue, the animal becomes extinct, not extinguished.
Those words sound pretty similar though, so you can see why he mixed them up.
Well spotted if you found that one.
This means all of the species will die out, not just most of the species.
Dodos and dinosaurs are examples of animals that this has happened to.
There weren't any mistakes in that sentence.
It's fine as it is.
And now the last sentence was all wrong.
Extinct animals will never be able to return to Earth.
They are gone forever.
Let's move on to the second part of our lesson now.
How animals become endangered.
The fewer of an animal species that there are, the more difficult it is for them to find partners and reproduce.
Think about it.
If there are 100 tigers in a rainforest, then they're going to find it much easier to find a partner and reproduce than if there are only five tigers in that rainforest.
When this causes them to be at risk of extinction, they're classed as endangered animals.
So when their numbers are so few that it is possible or likely that they may be unable to reproduce and to become extinct.
Scientists class the animals as endangered.
Usually action needs to be taken to prevent endangered animals from becoming extinct.
Whatever is causing them to drop in numbers needs to be addressed so they can continue reproducing plenty more of their species.
There are lots of things that can lead to an animal becoming endangered.
Like most things, these can be complicated and there can be a combination of different elements impacting on animal species at one time.
Do you have any ideas about what some of these things might be? If you have lots of thoughts to share, this will be a good place to pause the video and talk about these with a partner.
Time for another check-in on your understanding.
Alex and Aisha have been talking about endangered animals.
Who do you agree with? Aisha says, "I think an endangered animal is an animal at risk of becoming extinct." Alex says, "I think an endangered animal is an animal that will definitely become extinct." Pause the video here for some thinking time and perhaps some discussion time, and come back when you have decided on who is correct.
Did you know that it was Aisha who was correct? Endangered animals are at risk of becoming extinct, so it is a very real possibility, but it is not certain and there is still a chance to prevent extinction from happening.
Let's have a think about some of the threats to animals that are leading to them becoming endangered.
Deforestation is one threat to animal populations.
Deforestation is the removal of trees from land.
You can see deforestation taking place in the picture there.
Can you see how a large part of the land is now flat and all of the trees have been cut down? This happens for many reasons, including clearing land for use for farming or homes or cutting down trees to use their wood.
What could happen to some animals if trees are cut down? Think about what animals use the trees for.
Animals could lose their habitat and this makes it difficult to survive.
When the habitat disappears, they lose the places they shelter and they are likely to lose their food sources as well.
With nowhere to rest or hide from predators and very little food, it becomes very hard for these animals to survive.
If animals in one species don't survive, they cannot reproduce and the species becomes extinct.
Orangutans are one endangered species currently at risk of becoming extinct due to deforestation.
You can see an orangutan with its offspring in the picture there.
They really are beautiful animals.
Their forest habitats are being cut down to make way from mining and farming as well as gathering wood and palm oil from the trees, so all of those reasons there are to provide resources for humans to use.
Mining gathers metals and other materials.
Farming gives us meat and crops.
Wood is used for all sorts of things like building and furniture, and palm oil is used a lot in food products like chocolate and margarine as well as some cosmetic products like shampoo and lipstick.
Climate change is another way species are put at risk of extinction.
You've probably heard about climate change in the news or online.
Animals have adapted to the climate and the habitats that they live in.
When we say climate here, we mean the usual temperature and weather conditions in a place.
The ones that have been around for a very long time.
So the climate in our country is temperate with some rain.
If the climate changes, so if the weather and the usual temperature changes, animals may find it difficult to survive and reproduce.
This can be for lots of different reasons.
One famous example is the polar ice caps melting because of warmer temperatures causing problems for the polar bears who live and hunt on those ice caps.
There are lots of other challenges faced by animals due to climate change though, not just melting polar ice.
Changes in temperature and weather can affect animals' food sources, their access to shelter and their reproductive cycle.
Let's do a quick check for understanding.
What are some ways animals can become endangered? You might have noticed some in the question there, which gives you a clue that there might be more than one answer for this one.
We have A, deforestation B, a very cold day, C, climate change, and D, heavy rain.
What do you think? The correct answers here are D, deforestation and climate change.
Those are both things that have long-term impact on an animal's habitat.
Scientists who work to prevent species from becoming extinct are called conservationists.
Have you ever heard that word before? It comes from the word conserve, which means to protect something.
Conservationists work to protect living things.
They have developed a system of levels called conservation status to describe the risk of extinction of different animals.
Let's take a look at the different levels.
First, we have critically endangered.
Species that are critically endangered are at real risk of becoming extinct.
This is the most serious category.
And below that we have endangered, then vulnerable, near threatened, and least concern.
As you can probably guess, animals that are in the least concern category are not at great risk of becoming extinct and are the least in danger of all the categories, but conservationists are still keeping an eye on them because their numbers are beginning to drop.
Let's try a task now to find out more about the conservation status of different animals.
Carry out some research to find out the conservation status of these animals here and complete the table.
The animals we have to find out about are the African forest elephant, the monarch butterfly, the polar bear, the blue whale, the saola, and the black spider monkey.
Do you know what all of these animals look like? I'm excited to see what saola is like.
That's an animal I have never heard of before.
When you find out the conservation status of each animal, add it to the table in the correct row.
Pause the video now to have a go at carrying out your research and completing the table and come back when you are done.
Welcome back.
How did you find out about the conservation status of these animals? Let's see how you did.
The African forest elephant is critically endangered.
The monarch butterfly is endangered.
Polar bear is vulnerable.
Blue whales are endangered.
Saolas are critically endangered.
And the black spider monkey is classed as vulnerable.
Time for the final part of our lesson, researching endangered animals.
If an animal is under threat from deforestation or climate change, what impact might this have on its life cycle? Think about the different stages of the life cycles in animals.
Do you think any of them will be particularly vulnerable? This is a big question to think about, so you might want to pause the video here for some thinking and discussion time.
Endangered animals face challenges at all stages in their life cycles, so may become extinct.
Young animals might not have enough food or shelter to survive.
Younger animals are particularly at risk of starvation while they are growing and developing and they are easy prey for predators if they don't have anywhere to hide.
For animals that lay eggs, they may not have a suitable, safe place to lay them.
This could mean the eggs get broken before they're ready to hatch or even get eaten by hungry animals.
There may not be enough surviving animals to reproduce.
The fewer of a species that there are, the harder it will be for the animals in that species to find a partner to reproduce with.
If they cannot find a partner, then they cannot reproduce and make more of that species, leading to extinction.
Conservationists learn about the numbers of a species in the wild and their rates of reproduction by making observations of them.
As well as being really important work, this can be really exciting too.
Can you see the scientist in the photograph making observations of a sea turtle? Conservationists need to travel to wherever in the world the animals they're looking at live, so they visit all sorts of different habitats, including under the sea, jungles, and the polar ice caps.
How else could we find out about endangered animals and the threats to their survival? It's really important for scientists to do this work with the animals in their habitat, but that is not something we could do today to learn more ourselves.
How could we find out more about the threats to these animals survival? We can learn more about endangered animals by carrying out research using secondary sources.
We know that researching something means finding out about something or investigating it carefully and secondary sources are sources of information which have been created by others using findings from scientific inquiries.
The more we know about these animals and the threats that they face, the more chance we have of preventing their extinction, Even all the way across the world from some of these animals, if we know about the challenges they are facing, then there are things that we can do to help.
So it's important for us to find out about these challenges.
Let's have one more check for understanding before your final task of the lesson.
Can you answer this question? What are two ways we can find out about endangered animals? The question is asking for two ways so have a think and see if you can remember two different ways of finding out.
Pause the video here to have a try.
Let's see what we have then.
The two ways of finding out more about endangered animals are by making observations of animals in the wild, and by carrying out research using secondary sources.
Time for you to get stuck into another practise task.
For this one, you will be doing your own inquiry by carrying out some research.
Choose an animal from this list to research.
The animals are: African forest elephant, monarch butterfly, polar bear, blue whale, saola, and black spider monkey, And you might recognise this list, it is the same one we used before when we were finding out about conservation status levels.
So you can choose the animal you were most interested in earlier to find out more about.
When you have chosen your animal, find out A, what are the threats the animal is facing? We have looked at deforestation and climate change in this lesson, which are challenges for some of these animals here.
You might also find out about other threats they are facing as often endangered animals will be facing a combination of challenges.
Also find out B, how many do scientists think there are left in the wild? This one may be tricky because different scientists may make different estimates as no one knows for sure how many of the species are living in the wild.
When you're trying to find the answer for this one, look for the most up-to-date or recent information and maybe see what a couple of different sources say and evaluate which is likely to be the most reliable.
And also C, find out how the animal's life cycle is being affected by the threats.
Maybe the young animals are dying before they can become adults.
Maybe the adults are having difficulty finding partners to reproduce with or maybe there are other threats.
See if you can find out the difficulties of your chosen animal.
There's a lot to think about there, but I'm sure you're going to do a really good job.
Pause the video here and carry out your research.
Come back when you have found the answers to all of those questions.
Welcome back.
Were you able to find out lots of information about your chosen animal? Let's take a look at Aisha's research.
Scientists estimate that there are somewhere between 10,000 and 25,000 blue whales left in the wild.
Its main threats are habitat loss, becoming entangled in fishing equipment and the impact of climate change on their main food source, krill.
Now onto Aisha's research about how the animal's life cycle is impacted by the threats.
Blue whales may get caught in fishing deaths and die.
This is especially dangerous for young blue whales who are still developing their strength.
Blue whales may also struggle to find food at any point in their life cycle, meaning they may starve or not be fit enough to reproduce.
If there are fewer surviving adult blue whales then they are less likely to be able to reproduce.
This could lead to extinction if they're unable to reproduce at all.
You will have found out different things depending on which animal you researched.
If you looked into blue whales, then you've probably found similar information to Aisha.
If you researched a different animal, can you see any similarities between your animal and Aisha's? That brings us to the end of our lesson.
We have really packed a lot into this lesson, haven't we? Let's recap on the key learning points from today.
There are many things that can cause animals to become endangered, including deforestation and change in climates.
This disrupts their lifecycle and reproduction and may lead to them becoming extinct.
We can find out about endangered animals by observing them or by carrying out research.
Thank you so much for joining me today to learn all about endangered animals.
It's really important for us to learn about these animals and the threats that they're facing, so I'm so glad you chose to work hard today.
I wonder if you thought about what it might be like to be a conservation scientist and protect these animals in the wild.
It would definitely be exciting.
But now though, I'll say goodbye.
See you again next time!.