Hello, my name is Mrs. Mehrin and I am really looking forward to learning all about the evidence behind evolution with you today.

Let's begin.

Welcome to today's lesson from the unit Evolution and inheritance.

Your learning outcome today is: I can research a living thing that has evolved over time.

Now, I know that learning can be a little bit challenging sometimes, but that's okay, because it just means that we are going to work really hard together and we're going to learn lots of fabulous new things.

Let's begin.

So here are your keywords for today, and you have five keywords here.

Now, I am going to be referring to these keywords and the definitions throughout today's lesson.

However, if you find it helpful, you can pause the video here and jot these down.

Fabulous, well done.

Now, your lesson today is split into two parts.

Let's begin with the first part, evolution.

Now, the process by which living things change very gradually over a very long period of time is called evolution.

And when a species develops enough adaptations to make it significantly different from the original species, we say that it has evolved into a new species.

So let's do a quick check to see if you understood that.

What is evolution? Is it A, the way a living thing changes as it gets older, B, a characteristic that is inherited from a parent, or C, the process by which living things can change gradually over many generations over time? I'll give you five seconds to think about your answer.

If you need longer, you can pause the video here and you can come back once you're ready.

Off you go.

Fantastic.

The answer is C.

Now, we can use the theory of evolution to explain how the finches Darwin observed on different islands of the Galapagos had come to look different to each other.

So originally, a single species of finch from mainland South America settled on each of the different islands in the Galapagos.

So here, this tiny little island here, which is the Galapagos Islands, and you can see that circled on the map there.

Now, although these birds were the same species, there were small variations between their physical characteristics, so that's how they looked.

Now, some had slightly longer, shorter, wider, or thinner beaks, just like in the picture here.

Now, on islands which had lots of tiny seeds and small insects, the finches with longer, thinner beaks were able to gather more food.

Now, these individuals were able to survive longer than others, so were more likely to produce more offspring and pass on their thinner, longer beaks.

Now, this happened again and again over many generations until long, thin beaks became an adaptation that is observed in almost all of the finches living on on these islands.

They evolved into a new species of finch, different from the species living on the mainland.

On islands where the main food source was large berries and nuts, the finches with stronger, shorter, and wider beaks were able to gather more food.

They also evolved into a new species of finch over many years.

Now, although these two species of finch look different to each other now, they share a common ancestor that lived many generations ago.

This is why they still have many other physical characteristics in common.

Now let's do a quick check-in of your learning.

Why did the finches Darwin observed on different islands look different to each other? Is it because A, they had evolved differently over time as they were best suited to their own habitats, B, they had each flow to the island that had the best food source for their beak, or C, individual birds chose a style of beak that was best suited for their food source? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

The answer is A, they had evolved differently over time as they were the best suited to their own habitats.

Well done.

Now, evolution over time is the reason we have such a diverse range of plants and animal species on Earth.

And many different species have evolved from earlier types of living things, as they adapt over time to survive in different environments.

There are over 200 species of finches living across the world, including many species that live in the UK, and different species have evolved over many years in different habitats.

Diversity in plant species is also the result of evolution over time.

These plants share a common ancestor, but have evolved to have very different leaves to survive in different habitats.

So we've got a cactus here and a Venus flytrap, and these plants share a common ancestor, but they've evolved over time.

So they have different leaves to survive depending on the habitat that they live in.

Now let's do a quick check-in of your learning so far.

True or false? The huge variety of living things on Earth is a result of evolution over time.

Is that true or false? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

The answer is true.

Now let's see if you can justify your answer.

Is it because A, species have evolved from a common ancestor in different ways over many generations, or a species' features can evolve significantly in just one generation? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

The answer is A.

Now here is your first task for today, and it says, think about each of these statements and decide whether you think they are correct or incorrect.

So A says only animals can evolve, not plants or microorganisms. B, evolution sometimes happens in just a single generation of a species.

Or C, the variety of living things on our planet is the result of evolution.

So you are going to decide whether or not these statements are correct or incorrect.

So you have I am sure this is correct, I think this is correct, I think this is incorrect, or I am sure this is incorrect.

So I'd like you to pause the video here and have a go at doing this activity.

Off you go.

Fantastic, well done.

So we have got, here are your answers.

So you might have said, I think this is incorrect or I'm sure this is incorrect.

For B as well, I think this is incorrect or I'm sure this is incorrect.

And for the last one, I'm sure this is correct, I think this is correct.

Well done.

So now we are onto the second part of our learning, which is finding out about evolution.

So some children are talking about evolution.

Jacob says, "I've heard that evolution is just a theory." And Sofia says, "Does that mean it doesn't really happen?" What do you think? I'll give you five seconds to think about your answer.

Off you go.

Fantastic, well done.

So in science, a theory is a carefully thought-out explanation for something about our world that is based on evidence we have from scientific inquiry.

And since Darwin suggested his theory of evolution, scientists have gathered enough information for us to be sure that it does explain how living things change over time.

Now, what sort of evidence do you think we might have for this? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

So the fossil record provides us with lots of evidence for evolution taking place over millions of years.

And fossils found in lower layers of rock are older than those found in layers closer to the surface.

Now, can you see how the fossils are different in each layer of rock? So I want you to pause the video here and observe this cliff diagram really carefully.

How do you think the fossils are different in each of these layers? Off you go.

Fantastic, well done.

So the very oldest fossils are of very simple organisms. And fossils found closer to the surface are often of more complex organisms. This provides evidence that organisms have evolved in different ways, becoming more complex over time.

And you can see that because if you look at the bottom layer of this cliff diagram, you can see some really simple-looking fossils, and as you go up each layer until you get to the very top.

Scientists have found sequences of fossils from different time periods that show how certain types of living things have evolved over time.

Now, can you see how these fossils show how a whale shape has evolved from a land animal ancestor over millions of years? So here we have fossil skeletons, we've got more recent fossils and older fossils there.

So I want you to have a look at the fossils, and I want you to think, how does it show how a whale shape has evolved from a land animal's ancestor over millions of years? Have a really good look at this diagram here.

I'll give you five seconds to think about your answer, but if you need longer and you want to really observe carefully, you can pause video here and have a go at doing that.

Off you go.

Fabulous, well done.

So scientists can also gather evidence for evolution by looking at the living things that are alive today, and similarities between species suggest that they share a common ancestor, but evolved differently over time.

Now, can you see the similarities in these species here? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

So we can see that the nose looks quite similar.

It's pointed.

You can see that the ears generally are quite similar, but in the fennec fox, they're much bigger there.

The body shape is similar, but again, with the fennec fox, it's a lot thinner.

However, evidence gathered by scientists tells us that these species of fox once had a common ancestor.

Arctic foxes evolved to live in very cold habitats and fennec foxes evolved to survive in hot environments.

And scientists, such as evolutionary biologists, have used evidence from living animals and plants to support the theory of evolution.

Now, can you see the similarities in these animal skeletons? So we've got a whale, a frog, a horse, a lion, a human, and a bird.

So what similarities can you spot in these animal skeletons? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

So although these are not identical, the shape and structure of the bones in each animal share many similarities.

So this suggests all of these species had one common ancestor millions of years ago.

And each species evolved over time, their shape changing to be better adapted to their habitats.

Now let's do a quick check-in of your learning.

True or false? Similarities and differences between species that are alive today are the only evidence we have to support the theory of evolution.

Is that true or false? I'll give you five seconds to think about your answer.

Off you go.

Fantastic, well done.

The answer is false.

Let's see if you can justify your answer.

Is it because A, we don't currently have any evidence to support the theory of evolution, or B, we also have evidence from fossils and living things that support the theory of evolution? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

The answer is B.

Now, Aisha says, "I want to find out about the adaptations that have evolved in different types of penguins to help them survive in their different habitats.

I can't make observations of penguins myself, so how can I find out more?" So, what do you think? I'll give you five seconds to think about your answer.

Off you go.

Fantastic, well done.

So we can carry out research using secondary sources to find out more about how different species have evolved over time to become adapted to different habitats.

Now, it's important to use reliable secondary sources that are more likely to be scientifically correct.

So Alex says, "How can we make sure a secondary source is reliable?" I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

Well, Andeep says, "If someone I know has posted it on social media, it is probably reliable." What do you think? I'll give you five seconds to think about your answer.

Off you go.

Fabulous, well done.

So we can check to see who created the secondary source to see if it's likely to be reliable.

And are they an expert on living things and evolution? So social media posts are probably not the best one to use.

Now, we can also check more than one source to see if the information is the same.

If there are differences between different sources, at least one of them is likely to be incorrect.

Now, how can Aisha find out more about the evolution of different species of penguin? Can she A, carry out a fair test, B, carry out research using secondary sources, or C, read storybooks about penguins? I'll give you five seconds to think about your answer.

Off you go.

Fantastic, well done.

The answer is carry out research using secondary sources.

Now, here is your second task for today.

It says, using secondary sources, research and make notes on how emperor penguins and Humboldt penguins have evolved to survive in different habitats.

Your research should include what each penguin's habitat is like, what each penguin eats, how each is adapted to survive in its habitat, what similarities there are between both types of penguins.

So I'd like you to pause the video here and have a go at doing this activity.

Off you go.

Fabulous, well done.

So you may have put something like this.

For the emperor penguin, the habitat is Antarctica.

It has freezing temperatures.

It lays eggs and raises young on floating platforms of ice.

Its diet is mainly Antarctic silverfish, also other fish, krill and squid, which they dive deep into the ocean for to catch in their beaks.

Adaptations: layers of fat under skin for insulation.

Two layers of scale-like feathers to reduce heat loss by trapping body heat close to the skin.

Special circulation in feet to prevent them freezing.

Strong claws for gripping ice.

Relatively small wings and beak to reduce heat loss.

They can dive deeper than any other Antarctic bird, and are able to hold their breath for up to 22 minutes! Humboldt penguins.

Their habitat is the rocky shores near cliffs, off the coasts of Chile and Peru.

Warmer temperatures than emperor penguins, around 5 to 30 degrees, similar to England.

Their diet is mainly fish, such as anchovies, pilchards, and herring gathered on short, shallow dives into the ocean.

Now some adaptations.

Maybe patches of bare, pink skin around beaks to help them cool down in warmer temperatures.

Layer of fat under skin helps them to stay warm in cold water.

Torpedo-shaped bodies for fast swimming.

Similarities between emperor and Humboldt penguins is they have similar-shaped bodies, but different sizes, webbed feet for swimming, they're unable to fly, the spines on tongue to prevent fish falling out their beaks, and they have black feathers on backs and white feathers on chests for camouflage.

Now we are onto the summary of your learning today.

Evolution is the process by which living things can gradually change over time.

There are very many different kinds of plants and animals in the world today, and this variety of living things is the result of evolution over time.

The theory of evolution has been supported through a range of evidence, from fossils as well as living animals and plants.

The evolution of living things could be researched using secondary sources of information.

Well done for your fantastic effort today.

You have worked so hard learning all about the evidence behind evolution.

I am so proud of you.

Well done!.