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Adaptation, Darwin and Plate Tectonics



Learning Aims

Adaptation and Plate Tectonics
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Task 1 - What is Adaptation?


The first place we should start is by introducing you to two famous scientists. Well, one is rather more famous than the other but that is how it works sometimes. There is a Latin saying,  ‘Let he who shouts the loudest be heard first’ that seems to fit this situation very well. You will see what I mean once you have watched the BBC video 'Wallace and Darwin and the Theory of Evolution and Natural Selection'.


Well, what did you think of Darwin and Wallace? I felt a little sorry for Wallace especially when I heard about his ship catching fire and sinking.


Alfred Wallace Charles Darwin


Now, I said this was not going to be hard to understand so here it is.


Animals and plants live in a habitat, that is their home. For most animals and all plants, they can’t just get up and go somewhere else whenever they feel like it. I say most animals because if you remember we are animals and humans are very good at changing their environments.


I will give you an example. When you studied South America, you learned about the midge that pollinates the flower of the Cacao tree. Now, the midge lives in the leaf litter. If, we remove the trees so that there is no leaf litter the little midge can’t just pack his bags and go off to another part of the rainforest.


Polar bears in a sunny medow of flowers. One asks, where did all the ice and fish go? The other answers I don't know but it looks like grass for lunch.

If we drain a swamp the caimans that live there happily will not be able to jump on a plane and move somewhere else. Or if all the polar ice caps melt the polar bears that rely on the ice floes to catch their food can not just decide to turn vegetarian or swim to a new country.  In these instances, the animals would die.


Now, if you look all around the world you will find animals living very happily in their habitats. Darwin and Wallace wanted to know how these animals got to those habitats. Why do kangaroos live in Australia? Why do big cats only live in some countries and why are they all so different from each other? The animals didn’t choose to live in the best habitat for themselves.


So, the theory they came up with was one of adaptation and survival of the fittest. Most big changes in a habitat happen over a long period of time, millions of years. So the scientists proposed that the animals not suited to their environment would die, you can’t expect a tiger to breathe underwater it would not survive. Those that were really well suited would thrive and have lots of babies and those not very well suited may live but wouldn’t thrive and have fewer babies. This meant that the animals or plants that were best suited were having more babies and passing on their genes. Over long periods of time, there would be more individuals better suited to that environment and less of the ones not as suited. The fittest animal would survive.


Let’s look at this another way just so you really get it.


Poster illustrating adaptation. A family of blue long tongued anteaters reproducing at twice the rate as red short tongued anteaters.

The South American anteater has a long tongue that flicks 150 times every second! They are well suited to eating termites. The anteaters with longer tongues will eat more and be healthier, having more offspring (babies) who will have long tongues and survive better than the offspring of the anteaters with short tongues. You can see that very quickly, in a population with an equal number of both types of anteaters those with a long tongue will multiply, having two babies each, while those without won’t thrive as well (having just one baby each). Now, add to that the odd illness or death by being eaten by a polar bear (just kidding) and it is possible to see that the anteaters with short tongues could become extinct quickly. If there are enough small changes to an animal then eventually it will become a new species, it will evolve.


Of course, offspring do not always turn out identical to their parents so some short-tongued anteaters may have long-tongued offspring, for example.


Watch 'Living Things Change' by Crash Course Kids.

Very simply that is survival of the fittest and how a population adapts to its environment. You will learn more about this next year so do not worry if you don’t get it all.


Go and explore the material and play the game 'Peppered Moths'.


Task 2 - Examples of Adaptation


If you studied the South America Unit, you will already be familiar with the Pantanal, in Brazil. The conditions during the dry season on the Pantanal are very difficult to survive but animals do survive there. We are going to take a look at some of the survival strategies that animals have developed over time to enable them to survive in this hostile environment.


The first strategy you will already know about is migration.

American Golden Plover

The American golden plover, like many birds, just leaves when it gets tough. When the waters dry up they migrate back to the arctic tundra, 40,000km away!! But it isn't just birds that migrate fish do it too. When the water starts becoming sparse they migrate upriver.



Caimans and crab-eating foxes are tough cookies and they stay where they are. These two wait out the dry season by changing their diets, both rely more on insects than meat when the water is low.


A caiman

Crab-eating fox



Some frogs, you can read about different frogs of the Pantanal at joanneocock's website, bury themselves in the ground, shedding layers of skin to form a watertight cocoon. When the wet season begins they dig their way back to the surface.


Some animals, like the jabiru, have evolved to prefer the conditions of the dry season. These storks fly to the dry Pantanal as they are perfectly suited to catching fish and frogs in the muddy pools.



A jabiru


Task 3 - Research Adaptation


The Wildwood Trust has produced a lovely activity pack full of information about how different animals are adapted to their habitats. Take your time reading through the information pages (4-17) and then complete the activity sheets (18-29). Do not rush this, take as many days as you need to finish off the work. By the end, you will be a whizz at adaption.


Task 4 - Project


Using what you know about Darwin and Wallace, adaptation and evolution and how some animals have evolved different survival strategies I want you to make an infographic about animals that live in your country that have specialist adaptations. Maybe you have an animal that hibernates all winter or a bird with a beak tailored to catch its prey. Ask your grownup to help you identify some animals. You can roll out some lining paper and use Sharpies to create your infographic or maybe try using Canva. Choose whatever method works best for you, try to include:

  1. A short introduction to Wallace and Darwin

  2. Definitions of subject-specific words such as evolution.

  3. The name of the country and its climate.

  4. At least three animals and how they are adapted to survive.

Here are some examples of what an infographic looks like. Remember it is a non-fiction text - a non-chronological report.




Use the help sheet to improve your writing.


Checksheet of features of non-chronological reports


non-chronological checklist
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Task 5 - We Live On a Giant Ball


Let's take a closer look at the Galapagos Islands, where Darwin did his study, and how they were formed.


Go to this story map to see Darwin's journey.






Have you ever watched Ice Age~: Continental Drift? Scrat fell through to the centre of the Earth and landed on the core. He started running after his acorn and the land started to break up into pieces above him and drift apart. Well, that really happened and is still happening, well, the part about the land moving not about Scrat starting it!


Diagram of earths structure with a child standing on the crust which is grey. Underneath is the orange mantle and below that the red core.

The Earth is a giant layered ball. In the middle is the very hot, hard and heavy core, round that is the liquid mantle, which is still very hot and on top of that is the crust. The crust is the bit that we live on and it is very thin compared to the other layers.


Take a journey through the layers of the Earth in 'What Would a Journey to the Earth's Core be Like?' by Bright Side.




Now go and get some play-doh or something similar and using what you know about the Earth's structure create a model. You will need to have a hot ball in the middle, a thick mantle around that and a thin crust on top.


Next, ask your grownup to help you use a sharp knife to cut the model in half. Then using cocktail sticks and post-it notes which you stick around the sticks like a flag, make labels for the layers of your model. Add as much information as you can, go back and watch the video again if you need to so that you can teach your grownup all about Earth's structure.


Just for fun, you can't mention Continental Drift without doing the Sid Shuffle. Have a look and see if you can master it, maybe get your grown-up involved!



Task 6 - Plate Tectonics

The crust on your model isn't quite accurate. The crust is actually made up of 8 different sections, what we call tectonic plates and these plates just float on top of the liquid magma (hot rock) of the mantle. Now the magma is never still. The rock closest to the core gets the hottest and rises (just like hot air rises) towards the crust and cooler rock moves downwards to take its place. That cooler rock is heated, rises and the cycle starts again. Causing a convection current which makes the mantle act like a conveyor belt constantly moving the tectonic plates.



There are lots of different currents in the mantle just like in the ocean. Sometimes they move plates together sometimes they move them apart. This movement is very important to the Galapagos Islands. The Islands are located on the Nazca tectonic plate which is an oceanic plate, it has lots of ocean on it which makes it heavier. This plate is moving towards


the South American plate, a continental plate that has lighter land on it. As they collide the heavier Nazca plate slips down underneath the lighter South American plate. The rising continental plate (South American plate) has formed the volcanic mountain range called the Andes. The heavier oceanic plate (Nazca plate) sinks down into the mantle where it is heated and turns into magma.


Ok! But what about the Islands. Well, all that extra hot molten rock from the Nazca plate has to go somewhere, right?


Yes, it does and it goes straight up until it makes a hole in the crust. Magma pours out of the hole onto the ocean floor or onto land, magma outside of the mantle is called lava, and it cools to igneous rock. This rock builds up over time until a volcanic island or a volcano on land is formed.


Here an underwater volcano was caught on camera. There is not enough rock yet to make it an island but the volcano is trying really hard!




The Galapagos Islands are a group of islands, an archipelago. As the crust is constantly moving each island slowly moves off the hot spot in the crust where the magma breaks through and the formation of a new island begins.


In regions where the plates are colliding or pulling apart, there will also be a lot of earthquakes. After all, earthquakes are caused by the ground moving!


Watch this Brain Pop video called 'Plate Tectonics'.




So, that is how the famous Galapagos Islands were formed.


Task 7 - Galapagos and Darwin

You are going to learn a little more about the geography of this archipelago and Darwin.

  1. Go to Discovering Galapagos a Special Archipelago and complete the mindmap and explore the blog posts.

  2. Research Lonesome George and the Galapagos Islands.

  3. Go to the Darwin Correspondance site and complete the home learning activities.

Task 8 - Ring of Fire

Now it is time for you to do a little research with the help of Ruff Ruffman. Go to the site and click the launch or the arrow buttons to get started. Listen carefully to all the instructions. Good luck on your quest!





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