Lesson video

Hello, I'm Mr. Jarvis and I'm gonna be taking you through today's lesson, which is all about competition and adaptation in ecosystems. The lesson forms part of the unit on living organisms and their environments.

By the end of today's lesson, you should be able to describe what plants and animals compete for and to consider how adaptations help organisms to survive and compete in their environment.

There are five keywords in today's lesson.

They are competition, adaptation, physiological, extremophile, and microorganism.

Here are the definitions of those words.

I'll pause so that you have a little chance to read through those definitions and you can pause the video if you want to read through them in detail, but don't worry because we will go through the definitions as we move through the lesson.

Today's lesson is broken down into three parts.

First of all, we'll be talking about what competition in ecosystems is.

Then we'll move on to talk about how adaptations help organisms to compete for resources.

And finally, we'll talk about some of the organisms that live in very extreme environments.

So if you're ready, let's get started with our first part of the lesson, and that's all about competition within ecosystems. Ecosystems are made up of all the living organisms in a place.

The living organisms interact with each other, that's the biotic factors, and they interact with the non-living surroundings, the abiotic factors.

Habitats provide organisms with food, shelter, and a place to reproduce.

All living things within an ecosystem are interdependent, and that means that they depend on each other for the things that they need to survive.

Examples of this interdependence include animals eating plants for food, animals eating other animals for food, animals pollinating plants, and that provides food or fruits and enables plants to reproduce.

Animals also use plants to make nests and shelters, and decomposers return nutrients to the soil from things like animal dung and dead organisms. And plants use those nutrients from the soil to make their food by photosynthesis.

In any habitat, there are limited resources and there's competition for these resources between organisms because they need the resources in order to be able to survive.

And when we take part in a competition, we try and win something.

And what organisms are trying to do are to win part of the limited resource that's available.

So here's an example, two birds competing for territory.

Adaptations help organisms to compete for the resources.

And remember, an adaptation is a feature that helps an organism to live in a particular place.

Competition takes place within populations of one type of organism and also takes place between different populations of organisms, but all the time, it's for those limited resources.

There's competition within species and between species.

Let's look at a couple of examples.

So here in the first two pictures, we've got individuals within a population competing with each other.

In the top picture, we've got some bush buck, and in the bottom picture, we've got some cacti.

I'll pause for a few seconds to give you some time to think about what they might be competing for.

The bush buck are fighting and competing for space, and they're competing for the space because they're in a hot climate and they want some of the shade that's provided from the tree.

And so there's competition for that space under the tree in the shade to give them some respite from the sun.

The cacti are also competing for a resource, and the resource that they're competing for is nutrients from the soil and also some water.

Competition that takes place between individuals of the same population, it's called intraspecific competition.

Intra means within.

So it's within a species competition, intraspecific.

Let's look at another two examples.

Here we've got populations within a community competing with each other.

What do you think the resources that these species are competing for? Again, I'll pause for a few seconds.

So in the rainforest, there's lots of different species of plant.

There's lots of populations of plants that are forming the community, and they are all going to be fighting for light.

They want to get some light because that's important in making their own food.

The birds, we've got three different species of bird there, all fighting for a limited resource, which is food on a bird table.

Where we have individuals from different populations competing for limited resources, we call it interspecific competition.

Inter means between, for example, international, between nations.

So interspecific means between different species.

Here's a check.

What's meant by the term interdependence? Is it A, humans relying on other organisms for food? B, all organisms within a community relying on each other.

Or C, when an individual has what it needs to survive.

I'll pause for a few seconds and then we'll check your answer.

The correct answer is B.

Interdependence is when all organisms in a community rely on each other, and that's usually for a resource.

Here's another one.

Why does competition take place between organisms within an ecosystem? Is it A, several organisms need a resource to be able to survive? B, competition decides which animals are most important in an ecosystem.

Or C, there has to be a winner to keep an ecosystem healthy.

Again, I'll pause for a few seconds and then we'll check your answer.

This time the correct answer is A.

Competition takes place between organisms within an ecosystem because several organisms need a resource to be able to survive.

Well done if you got that.

Competition in plants.

Plants compete for lots of different resources, such as light to make food by photosynthesis, water for photosynthesis, and help to support them, nutrients from the soil for healthy growth, space so that they're able to get the light, water and nutrients that they need, and pollinators and to help with seed dispersal.

And you can see on the the bottom picture, I've circled some seeds from a plant that are sticky and have hooks that stick themselves to the fur of animals that walk around.

Plants have adaptations to help them avoid competition.

Woodland plants grow and flower very early in the year.

Snowdrops, as an example, grow and flower before the trees are in leaf so that they get the light, nutrients from rotting leaves from the previous season and have access to plenty of water.

Plants use different methods to disperse seeds to avoid competition.

So coconuts often will fall into the sea and travel long distances.

Because they float, they can travel on the sea for weeks before they wash up on the soil and germinate.

Some seeds use the wind, for example, dandelions, and others are dispersed by exploding seed pods that scatter seeds several metres away from where the adult plant is growing.

If we look at competition in animals, animals compete for food and water.

Here for example, we have some hyenas and vultures who are scavengers competing for meat that's left from a lion kill.

They compete for territory or shelter.

And here we've got some anemone competing for space in the rock pool.

Or they compete for mates, and male crickets sing to attract mates by rubbing their back legs together and the females are attracted by the different songs.

Animals have many adaptations to help them to compete and survive.

There's competition for food and territory, as an example, is very high, and that's because many herbivores eat the same plants.

Carnivores have to have good adaptations to catch prey and animals defend their territory.

Competition for a mate within a species is really high and many males put in lots and lots of effort to impress females, even fighting to show how strong and dominant they are.

Here's a question.

Which of the following are resources that animals compete with other organisms for? Is it A, food, B, shelter, C, nutrients from the soil or D, seed dispersal? I'll pause and give you some time to answer.

The correct answer is food and shelter, A and B.

Well done if you got that.

So let's move to our task.

Organisms are in competition with other organisms for limited resources to survive.

I'd like you to draw a concept map to show the different resources that organisms compete for within ecosystems. I'd like you to remember to think about both plants and animals.

So draw your concept map and then label it with some lines to say the sorts of resources that animals and plants are likely to compete for.

You'll need to pause the video, write down your answer, and then when you're ready, press play and we'll check your answer.

I asked you to draw a concept map to show different resources that organisms compete for within ecosystems. When we go through the answers, I'd like you to add any resources that you've not listed to your own concept map because we're gonna be using this later on in the lesson.

So answers that you should have got are food, water, minerals, space, shelter or territory, mates, light, pollinators and seed dispersal.

Well done if you managed to get all of those.

That brings us to the second part of the lesson today, which is all about how adaptations help organisms to compete.

So if you're ready, let's move on.

There are three main types of adaptation that we see in animals and plants.

Structural, which is changes to the appearance of an organism.

For example, leaves are modified into spines on cacti to prevent water loss and to help to defend against being eaten by herbivores.

We also see long eyelashes in camels.

That's to help stop the sand being blown into the camel's eye.

We also have physiological adaptations.

One example are the poisons that are produced by plants, in this case, nettles.

If we touch nettles, they produce a rash on our skins.

That's again designed to stop the nettle from being eaten.

Sometimes cells can cause an organism to change its colour.

Here we've got an octopus that's able to use physiological features to enable it to change colour and to match its background, and that helps to camouflage it from being eaten.

And finally, we have behavioural adaptations.

For example, plants grow towards the light and they also grow their roots down towards the water or animals that behave in different ways at different times of the year.

For example, migrating to other countries where it's warmer or more suitable for the organism to live, or organisms that are nocturnal or hibernate over winter.

Adaptations help all organisms compete and survive in their habitat.

And there are many, many, many different adaptations.

Plant adaptations include reducing the exposed surface area of leaves to help them conserve water.

Here we've got a marram grass that lives on sand dunes where water doesn't hold in the soil; it drains all the way through really quickly.

And so the leaf is curled round to reduce its surface area so that it doesn't lose too much water.

Some organisms collect and store water, and they do that by having long tap roots as seen in the dandelion plant in the top picture in the the centre.

And in cacti, the actual fleshy stems are adapted to enable them to store water to use at times when it's really, really dry.

Other adaptations include increasing the surface area of leaves to help absorb light.

And we see that in things like water lilies that spread out over the surface of water so that they can absorb as much sunlight as they possibly can.

And the bottom picture is a picture of a plant that you would find in a forest habitat and it spreads itself out along the floor so that as much light as possible is absorbed through the leaves.

The Saguaro cactus is adapted for living in the desert as one particular example.

And the flowers of this cactus are located in a particular place on the cacti stem right at the top.

It has an adaptation, which means that it relies on bats for pollination.

There's lots of competition for pollination in the desert and the flowers of this particular cactus open at dusk just at the time when bats start to move around.

It also produces a really strong scent, which is attractive to the bats.

The flowers contain huge amounts of nectar and they're found right at the top of the cactus stem so that it allows easy access for the bats to drink.

When the bats feed, the bats transfer the pollen from one flower to another, and that means that the plant gets pollinated and is able to reproduce.

Animal adaptations include adaptations to cold habitats.

Examples include huddling so that heat is conserved between organisms. Thick fur are to help keep them warm, layers of fat seen in the walrus and padded feet to help insulate the body and also to give grip on slippery surfaces.

We've also got adaptations to hot and dry habitats, and here we've got some organisms that live in these sorts of places.

The fennec fox in the top left-hand corner has large ears that help it to lose heat from its body and stop it from overheating.

The camel has a hump that contains fat, not water, but the fat can be converted into what we call metabolic water so it has to drink less often.

Dung beetles make use of the dung of animals and they use that A, to feed and to get water and moisture, but also as a habitat for their larvae.

We've already talked about long eyelashes of the camel to stop the sand from blowing in the eyes.

And also, we've got a rattlesnake here that is using the rocks to be camouflaged and to also bask out in the sun to maintain its body temperature.

Other adaptations include catching prey, avoiding being eaten, and eating specific types of food.

Here we've got things like binocular vision, having the eyes at the front of the head pointing forwards, that helps to judge distance.

Sharp teeth and talons help predators to catch their prey.

Teeth, such as these horse teeth, allow organisms to eat grass that's perhaps short.

And having tools to get specific food, such as this hummingbird beak, which allows the beak to probe deeply into a flower to drink nectar as food.

Or we have camouflage.

And camouflage is important for predators to hide from the prey that they're stalking, but also by the prey themselves to stop predators from seeing them easily.

And here we've got two examples.

First are two deer that are within a tree environment.

And secondly, we've got some frogs that are sat by the side of a pond and blending into their surroundings.

Let's move to a check.

I'd like you to look at these three images of an elephant's foot, scorpion venom and bat hibernation.

And I'd like you to decide what type of adaptation each picture shows.

Is it A, a structural adaptation, B, a physiological adaptation, or C, a behavioural adaptation? I'll pause for five seconds.

If you need a bit more time, you can pause the video and restart it when you're ready, and then we'll check your answer to see if you've got the answers right.

Good luck.

So the elephant's foot is a structural adaptation.

The foot is adapted so that the elephant doesn't sink into the ground.

The scorpion venom is made by cells, and so that's a physiological adaptation.

It's B.

And bats hibernating is C, a behavioural adaptation.

Well done if you got those three right.

Now we're gonna move to a task.

I'd like you to use your concept map from task A to provide at least one adaptation of a named organism for each resource that helps the organism compete successfully for it.

And I'd like you also to say whether your example is a structural, a physiological, or a behavioural adaptation.

Here is a reminder of the various resources that are competed for by organisms that we completed at the end of the first task.

You'll need to annotate your own.

You'll need to pause the video, add to your concept map, and then when you've got them all done, press play and we'll check your answers.

Good luck.

I asked you to name for each resource on your concept map at least one adaptation of a named organism that helps that organism compete successfully for the resource, and to tell me whether it was a structural, physiological or a behavioural adaptation.

So let's look at the answers.

So for food, you might have said something like claws to catch food, for example, a lion, beaks to tear flesh from bones, for example, a vulture and their structural adaptations.

You could have said venom to paralyse prey from something like a scorpion or a spider.

That's a physiological adaptation.

You might have said bing able to hunt at night, for example, bats, that's a behavioural adaptation.

You might have said camouflage, changing colour, for example, chameleons or octopus, that's a physiological adaptation too.

Competing for water.

You might have said long roots that enable a plant to reach water as seen in a cactus and a dandelion, that's structural.

Competing for minerals, for example, attracting insects and digesting them to provide minerals in the soil as is seen in carnivorous plants.

That's both a structural and a physiological adaptation.

It's structural because the part of the plant is modified to enable them to catch the insects and it's physiological because they need to produce smells that might attract insects to them in the first place.

And then they need to produce chemicals that enable the insect to be digested so that the minerals are released into the soil.

Space, shelter and territory.

You might have said claws to dig into the ground to build warrens, such as rabbits.

That's a structural adaptation.

Competition for mates.

Examples here are brightly coloured tails and performing to impress females, as you might have seen in the peacock.

That's both, again, a structural adaptation because of the tail.

The tail is the thing that's the structural part.

The behavioural is the dance that the males use to impress the females.

Competing for light, growing and reproducing early in the year before trees are fully leaved, as seen in things like daffodils and snowdrops.

That's a behavioural adaptation.

Pollinators competing for pollination by producing attractive scents and nectar to attract insects as seen in things like roses.

That's a physiological adaptation.

Cells produce the scent and the nectar.

For seed dispersal, light seeds are easily carried in the wind, for example, dandelions, is a structural adaptation.

You might have found out an example of a seed pod that explodes, and again, that's a structural adaptation too.

Well done if you managed to think of an example of an adaptation for each of those resources.

That brings us to the third and final part of today's lesson, which is all about living in extreme environments.

So if you're ready, let's move on.

There are places on the planet where organisms live in the harshest of environments, and this includes where temperatures are extremely high or extremely low, where conditions are highly acidic or highly alkaline, where pressure is very high or where there's very high salinity.

And some examples of these sorts of environments where organisms live are hot volcanic springs or places like the Dead Sea, where it's extremely saline, extremely salty.

Organisms that live in these type of environments are called extremophiles.

The word extremophile can be broken down into extremo, which relates to extremes, and phile, which means to love.

So organisms that are extremophiles love to live in extreme places.

Most extremophiles, but not all of them are microorganisms and microorganisms are small organisms that can only be seen using a microscope.

Many of these microorganisms are things like bacteria.

Some extremophiles live at very high temperatures and some bacteria can live in hot springs.

Here's a picture of a hot spring, and the yellow and orange streaks that you see here are caused by algae and bacteria.

The temperatures of these hot springs can often be above 80 degrees Celsius, and they have specially adapted enzymes which don't denature at these very high temperatures.

Similar adaptations allow some bacteria to live at temperatures well below zero.

For example, in sea ice.

Some extremophiles are able to live deep in the oceans, and the deeper that you go under water, the more the pressure increases.

There's also very little light at this sort of depth, and the water is very cold and salty and organisms here need to have adaptations that help them to survive.

The viperfish, which is shown in the diagram, has what's called bioluminescence to attract prey and avoid predators.

They have lures and they flash specialised cells to mimic water movements and to avoid predators, but also instil curiosity of some of the prey species that it might feed on right deep into the sea.

Some extremophiles are also able to live in very acidic and alkaline environments, such as these deep sea urchins, which live near volcanic vents.

They turn over the sediment to find organisms to eat.

The temperature here is really warm because it's near to a volcanic vent, but the water that's heated is also often highly alkaline.

They have a number of physiological adaptations that help them to survive.

A small number of extremophiles are able to survive in high salt conditions.

The Dead Sea in Israel is not actually dead.

A very small number of bacteria can be found in the water.

This can be a really difficult environment to live in because salt causes problems with water balance and some bacteria have adaptations in their cytoplasm, which means that they don't lose water from the cells by the process of osmosis.

Here's a check.

Scientists have found microorganisms inside rocks from deep caves.

They've been trapped in the rocks for thousands of years.

The caves are dark, very hot, humid, and acidic.

Why are these organisms extremophiles? Is it A, because they're old, B because they live in the dark, C because they in high humidity, D, because they live in acidic conditions, E, because they live at high temperature or F, because they live inside a rock? I'll pause for a few seconds.

You can decide which answer or answers are correct and then we'll check your answer.

The correct answer is D and E.

They're extremophiles because they're living in very acidic conditions, and they're living at very high temperatures.

Well done if you got that.

Let's move to our final task of the lesson.

Anglerfish live deep in the sea, usually at depths of over 1,000 metres where the pressure is very high and the water is very cold.

Sunlight only passes about 100 metres of depth in clear water, and these fish have all lure, a rod-like structure, that contains bioluminescent bacteria that produce light.

I'd like you to write a paragraph to suggest how this lure containing the bioluminescent bacteria might help the fish to survive.

You'll need to pause the video, have a think, write down your answer, and when you're ready, press play and we'll check to see how well you've done.

Good luck.

Let's see how you did.

I asked you to write a paragraph to suggest how the lure containing bioluminescent bacteria might help the anglerfish to survive.

Possible answers that you might have suggested include the bioluminescent lure lets the angular fish see as its dark at this depth of the ocean.

Remember, I told you that light only went 100 metres down in clear water.

It attracts prey to the lure, which the anglerfish can then eat.

It might attract mates to enable the fish to reproduce, and it might allow the anglerfish to see predators and avoid being eaten.

Well done if you gave any of those answers.

That brings us to the summary of today's lesson.

We've seen that organisms within a community are in competition with each other for the limited resources that are available.

For example, food.

We've seen that organisms are interdependent and that means that populations rely on and can impact on each other.

Organisms have adaptations which help them to compete and survive, and these adaptations can be structural, physiological, or behavioural.

We've seen that some organisms are adapted to survive in extreme conditions, and these organisms are called extremophiles and many of the extremophiles that we see are microorganisms. Microorganisms are organisms that we can only see under the microscope.

I hope that you've enjoyed today's lesson and I hope to see you again sometime soon.

Take care for now.