Lesson video

Welcome to this lesson from the Oak National Academy.

This lesson is taken from the unit, adaptations, competition, natural selection and evolution, and it's about competition or more specifically, we'll be talking about the struggle for resources that all living organisms take part in.

Hi there.

I'm Mrs. Wheat and I'll be taking you through today's lesson.

By the end of today's lesson, you'll be able to describe resources that organisms have to compete for and explain how adaptations can be helpful.

Let's look at our keywords.

There are five keywords for today's lesson, competition, variation, adaptation, advantage and fittest.

Now let's look at our definitions.

So before I show you the definitions, you don't need to memorise all of these right now.

I'm gonna be explaining each of them in plenty of detail when they come up during the lesson.

But if it helps you feel more confident about it, then feel free to take five seconds to read them through or you can pause the video, write them down and then click play when you're ready to continue with the lesson.

So here they are.

Today's lesson is in two parts.

First of all, we'll talk about competition in animals.

We'll talk about the resources that animals compete for and the various strategies they have in order to compete for them.

And then we'll do the same in plants.

What do plants compete for? What strategies that they have to help them compete? But first of all, competition in animals.

All living organisms need resources from their habitat.

There are limited resources available in each habitat.

You might have heard the word finite resource before.

So finite, that's the opposite of infinite.

Infinite meaning it goes on forever, it doesn't run out.

Finite means the opposite, right? So it won't go on forever, it will run out.

Living organisms are in competition for limited resources in order to survive and reproduce.

So if the resources that living things needed were infinite, then they wouldn't need to compete.

There wouldn't be this struggle, which is really what competition is about, it's a struggle for limited resources.

There wouldn't be this struggle, because every organism would just go and get exactly what it needs.

But because there's a limited amount, a finite amount, they compete in order to get them, in order to have access to them.

Let's take a look at these pictures.

We've got some stag beetles fighting.

Maybe they're competing for a mate or they're competing for territory or shelter.

We've got some birds on a bird feeding table, potentially in competition for food.

And again, we've got some antelopes physically fighting, potentially for mates.

Now, let's look at some of the strategies that living organisms have to help them compete.

So not all organisms are the same.

There's variation between them and that might seem really obvious when we're thinking about human beings.

I'm sure if you're sat in a classroom right now or even if you're just at home with your family, you know that not all human beings look the same.

We look really, really different.

We have different hair, different skin colours, different eye colours, different heights.

And so it's easy to see variation between human beings, 'cause we're so used to them.

But maybe if we look at my examples here, we've got two different bird species.

We've got a kingfisher eating a fish and we've got some owls.

You might not be able to tell the difference between each individual kingfisher or each whatever species, this owl is each individual of that species, they might all look the same to you, but there are differences and we can't really see them, because, well, I'm not a kingfisher expert, I'm not an owl expert, but the differences are there, trust me.

Maybe if you're a pet owner, you'll think about the fact that, oh, okay, well it's easy for me to see the difference between my dog and someone else's dog.

But if you're not into pets, you don't have a dog, you don't have a cat, maybe they all kind of look the same to you.

It's only just 'cause we're not around these creatures a lot, we kind of tend to think about them as all being the same, but they're not and there is a lot of variation between them.

So some variations are adaptations that help organisms to compete for resources, such as food or places to live.

So these differences between them, the variations, some of them are adaptive, helpful, useful in order to gain resources.

These adaptations give these organisms an advantage in competition.

Let's take this kingfisher for example.

Let's imagine this kingfisher is the best flyer in the area.

It's got really, really powerful wings.

So that's how it's different to the other kingfishers, which would be variation.

Not only is it different, but that variation it has, it's an adaptation, it's useful, it allows it to get more food.

So that's an advantage over the other slower kingfishers.

And so it can compete and get more food and is more likely to survive and reproduce.

Let's look at the owls.

Maybe these owls have even more camouflage markings on their feathers than the other owls in the area.

Again, that's a difference, okay? Their feathers are different, variation.

So it's an adaptation, 'cause it's helping them in order to hunt food, prey can't see it coming as easily if you're really well camouflaged.

That's an advantage.

They're more likely to get more food than the other owls of their species, and so they can compete more successfully.

So that's how that works.

Let's see if we understood that.

Which word describes the struggle between organisms for resources? Is it A, adaptation, B, advantage, or C, competition? You've got five seconds now or pause the video to give yourself some more time.

Click play when you're ready to see the answer.

It is C, competition.

A, adaptation, that was variation that allows the organism to get something that it needs from its environment.

Advantage, that was describing how some organisms because of the adaptations, are better at getting the resources they need.

And the struggle between organisms for resources is competition.

Well done if you got that right.

So in science, we say that the best adapted organisms are the fittest, because they're the best fit to their environment.

Now, lots of people think that this word fittest is just about physical strength and it definitely can be about physical strength.

It's useful to be strong in lots of situations, but it's not just about that.

So the fittest animals are more likely to compete successfully, survive and reproduce.

We'll look at a few examples.

We've got this peacock.

This peacock isn't particularly physically strong, but it has absolutely amazing feathers.

And those feathers are for attracting females of its species.

So that's the way it could be biologically fit.

We've got this lion.

Potentially this lion has really, really powerful jaws, really strong bite strength, bite force and so that is an example of physical strength that could be associated with biological fitness.

If we look at this lizard, again, this lizard isn't particularly strong, but it's really well camouflaged.

If this lizard was bright pink, you'd be able to see it.

That's not a good idea for this guy, okay? So we've got three different examples of biological fitness in three different situations.

It's not just about strength.

So organisms that are less fit or you could say poorly adapted are less likely to compete successfully and more likely to die before reproducing.

So let's think about the lizard again.

So if this lizard was bright pink, that's very, very poorly adapted to its environment, it does not live in a bright pink environment.

So it's not camouflaged.

It's gonna be easier for prey to see it coming and easier for predators to then go eat it.

And so that's what we're talking about with biological fitness.

Okay, let's check to see if you understood that.

What does fittest mean when thinking about organisms competing for resources? Is it A, the strongest organism, B, the most athletic organism, C, the best adapted organism, or D, the smartest organism? Take five seconds or you can pause the video to give yourself some extra thinking time.

Click playing when you're ready to see the answer.

It is C, well done if you've got that right.

Let's look at some specific examples.

Animals compete for the following resources, food and water, shelter and mates.

And animals have a variety of adaptations that allow them to successfully compete for these resources.

Let's see if that made sense.

Complete the sentence about competition in animals.

Animals compete for mates, food, water and what other resource? Take five seconds or pause the video.

Click play when you're ready to see the answer.

It is shelter.

Well done if you got that right.

So we're gonna look at some specific examples of animals and different resources they compete for.

So we'll start with food.

Just to note, I could have picked, there's so many different examples I could have picked.

I don't know everything about all the animals that ever existed.

So these are just three examples that I knew about that I chose, but I'm sure you know things as well from watching nature documentaries or having pets, being around animals.

And maybe you can have a discussion about the animals you know about and something they compete for and how they're adapted to do that.

So here's just a few examples.

So birds' beaks are highly specialised for the type of food they eat.

So if they eat nuts and seeds, they need really short, hard beaks in order to crack open the seeds.

Right now we're looking at a hummingbird.

So hummingbirds drink nectar from inside of flowers and so some hummingbirds are born with especially long thin beaks and this helps them to reach even further inside the flower.

This gives them an advantage over hummingbirds where they were born with shorter beaks and the hummingbirds with longer beaks are more likely to drink more nectar.

That's really, really useful and this makes them more likely to survive, 'cause they get more food and then they can reproduce.

So that's one resource, food, one adaptation that an organism has in order to get resources and how it helps it to compete successfully in its environment.

Let's look at another one.

So I've got two different animals here.

I've got a meerkat and I've got some Ural owls.

So animals can be fiercely territorial over their shelter.

Some animals mark their territory with urine and faeces, pretty gross.

So meerkats do that for example.

They don't want other meerkats sharing their shelter and so they mark their territory that way.

Birds can use song to let other members of their species know that this territory has been claimed, which I personally think is a much nicer way than spraying your home with urine and faeces.

Some animals are also physically aggressive at their shelter.

Meerkats are aggressive as well about other meerkats coming to their territory, coming to their shelter, and birds are too.

Competing for the best shelter available ensures a group of animals has enough space to raise their young and avoid overcrowding.

So this isn't just about being comfortable, like, oh like, I need more space in my environment.

But overcrowding is dangerous for organisms, 'cause it's then easier to spread disease that way.

So this is huge advantages for a species that's able to successfully guard their territory.

Okay, one more example.

Animals can have very different strategies for how they compete for mates.

So some animals fight to demonstrate their physical strength, like this deer, these two stags are fighting with each other so they can have access to mates in their herd.

That's probably the most common way that people think about competition for mates, but there are other ways of competing for mates.

So others put the energy into growing impressive features, such as brightly coloured feathers, like this blue peacock, which I think is a way better way of attracting a mate, just being super amazing looking.

Much more fun than fighting.

Animals that create the most impressive display, so either that's strength or whether that's having really impressive features, are more likely to be chosen to mate with.

And so there again, those are two very different strategies, but they both help them be biologically fit and help them to compete for the resources, as in mates, that they need in order to survive and reproduce.

Let's see if you understood that.

So some penguins are brought to an island.

There is a limited amount of food on this island.

Which of these is the most likely outcome? Is it A, the penguins cooperate and share the food so that there is enough for all of them, B, the penguins compete for the food and the fittest penguins survive, C, the penguins collaborate to make sure they find enough food, or D, the penguins compensate by eating less so that all of them can survive? Take five seconds or pause the video to give yourself some extra thinking time.

Click play when you're ready to see the answer.

It is B.

Now, lots of these other examples would've been much nicer.

Wouldn't it be lovely if the penguins cooperate and share the food so there's enough for all of them? Wouldn't that be nice? But I'm afraid that isn't the most likely outcome.

Food is a finite resource, so in order to make sure that organisms get enough food in order to survive, they're gonna be quite protective of it.

They're gonna compete for it, potentially physically, or maybe just being a better hunter or craftier and then only the penguins that are the best adapted to getting the food, the fittest penguins are the ones that are likely to survive.

Well done if you got that right.

Let's have go at our first practise task.

Red squirrels are a native species of the United Kingdom.

Grey squirrels are not a native species and were introduced to the UK from North America.

Grey squirrels successfully out-competed red squirrels and now they are the dominant squirrel species in the UK.

So use the table to explain why grey squirrels out-competed red squirrels in the United Kingdom.

So we've got grey squirrels and red squirrels at the top.

We've got different criteria down the side.

So for food, grey squirrels eat nuts and seeds, red squirrels eat nuts and seeds.

The habitat for the grey squirrel is woodland.

The the red squirrel is woodland.

Number of offspring, grey squirrels have three to four.

What are squirrel babies called? I need to look that up.

Squirrel babies apparently are called kittens.

So for the grey squirrel, they have three to four kittens in a litter, in like a batch of babies that they have.

And red squirrels have two to three kittens in a litter.

So grey squirrels for squirrel pox virus, they are immune to this deadly disease for squirrels.

But red squirrels have a high death rate from the squirrel pox virus.

Grey squirrel behaviour, they tend to be shy and they tend to hide, but red squirrels, they are aggressive and they fight more.

So use the information in this table and explain why grey squirrels out-competed red squirrels in the United Kingdom.

You'll need to pause the video for a few minutes to give yourself enough time to write your answer and then click play when you're ready to see the answer.

Let's see how you did.

So red and grey squirrels eat the same food so are in competition with each other for this limited resource.

They have the same habitat so compete with each other for shelter.

Grey squirrels have more offspring so they can grow their population faster than red squirrels.

Grey squirrels are immune to the squirrel pox virus so are more likely to survive than the red squirrels when they come into contact with it.

And grey squirrels are more likely to hide and stay safe, but red squirrels are more likely to get into fights where they can get injured or killed.

Great work if you got that right.

So we've looked at competition in animals, what animals compete for and how they compete for it, and now we're gonna look at competition in plants.

Plants also compete for resources, but they compete for different things.

So they compete for pollinators, seed dispersers, water and minerals, light and space.

Plants have a variety of adaptations to help with them compete for resources.

Let's see how we're doing so far.

For each of the following resources, identify whether competition occurs among plants, animals or both.

Take five seconds or pause the video to give yourself some extra time.

Click play when you're ready to see the answers.

Let's see how you did.

So for water, that's both.

For food, just animals.

Minerals, that's plants.

Space, plants.

Pollinators, also plants.

Shelter, that's animals.

Seed dispersers, plants.

Mates, animals.

And light, that's plants.

Great job if you got that right.

Many plants produce nuts or fruit containing seeds, so here we've got a red squirrel, which looks like it's eating an acorn and we've got a barbary macaque, a type of monkey, that looks like it's eating the remnants of some piece of fruit.

So these nuts or seeds are eaten by animals and when the animal defecates, that's scientific for poo, this deposits the seeds on the ground so a new plant can grow.

So that acorn that the squirrel is eating, it's made up of lots of fat and protein, which the squirrel wants to eat.

That's attractive to the squirrel.

So the squirrel eats it and then it travels around and then when it defecates, the seed comes out in the squirrel's faeces and goes into the ground.

That seed then is essentially planted in this pile of fertiliser, the squirrel poo, and it gives it a really, really great opportunity and a good chance of growing in a new environment.

Plants that produce the most or best fruits and nuts are more likely to attract seed dispersing animals, like squirrels, like monkeys.

This increases their likelihood of having offspring, that's the new plant.

So again, plants are competing for these seed dispersers.

There's only so many squirrels.

There's only so many monkeys, only so many birds.

These animals are gonna want to eat the best tasting fruit or the nuts and seeds that have really, really high fat and protein content.

So the plant producing these things is its way of competing and trying to attract these seed dispersers to them.

Okay, let's see how you're doing.

Which of these plants would be most likely to successfully compete for seed dispersing animals? Is it A, a plant that produces lots of brightly coloured leaves? B, A plant that produces lots of brightly coloured fruit, or C, a plant that produces lots of brightly coloured flowers? Take five seconds or if you need more time, you can pause the video.

Click play when you're ready to see the answer.

It is B.

A seed dispersing animal is most interested in a plant that produces lots of brightly coloured fruit.

Well done if you got that right.

Okay, now let's look at water and minerals, another thing that plants compete for.

So plants need water to survive and minerals to make compounds essential for their health.

Plants grow roots to absorb water and minerals from the soil.

So if you look at my picture, we've got some grass, a type of plant, we can see their roots underneath the ground.

So they're growing that in order to absorb the water and the minerals from the soil.

Plants with roots that are best adapted to absorb water and minerals are more likely to survive and reproduce.

So they'll be more likely in order to get all of the water and all the minerals they need to ensure survival and to ensure healthy growth.

Here's an example that you may have known about already, light.

Leaves absorb light to provide energy for photosynthesis.

Remember that's the process by which plants make their own food, glucose.

Plants that have lots of leaves or leaves with a larger surface area, like this giant water lily in the picture, those are enormous, they are more likely to absorb sunlight.

This means they can carry out more photosynthesis to make more of their food, glucose.

And if they've got more food, glucose, this increases the likelihood that they can survive and they can produce seeds and reproduce.

Okay, the last thing that plants compete for is space.

So plants need plenty of space to grow healthily.

Plants that grow too close together compete for light.

So growing in the shadow of another plant reduces the chance of the plant getting enough light for photosynthesis.

So if you think about it like a big, big oak tree and we've got lots of tiny plants growing underneath.

When you next go out and walk around and you're in a park or whatever, have a look at some of the big trees and look at what's growing underneath them.

It's probably not very much.

You probably won't find another huge tree growing under a huge tree, 'cause it can't get enough light for photosynthesis.

You might have some grass, 'cause they have much lower light needs, but a lot of the time you just have this big like earth and patch underneath it, 'cause nothing can grow, because the huge tree is blocking out the light.

So that's why that happens.

So another thing that plants are in competition for if they're too close together is water and minerals.

So if there's a lack of space for roots to grow, then this reduces the likelihood of gaining sufficient water and minerals.

So space is an interesting thing that plants compete for, 'cause it kind of incorporates other things the plant needs to compete for as well.

So this is why plants have tonnes of strategies for dispersing their seeds.

So if we look at my two pictures, I've got a dandelion.

Hopefully at some time in primary school you picked a dandelion, you've blown on it to send the seeds go scattering.

And the reason that the dandelion is like that is because it's a really, really useful adaptation.

So when the wind blows, this scatters the seeds and the new dandelions that grow from those seeds are really far away from the parent plant.

The parent plant is really tall.

If a seed grows directly underneath it, the parent plant when it's growing, its leaves are likely to block out light for the offspring.

And so the offspring will be less successful, less likely to get the light it needs, less likely to survive.

And so scattering its seeds by having that design where the wind blows and it scatters them everywhere is super, super useful.

And then we've already talked about this a bit with fruit.

So here I've got an apple tree.

That tree is producing lots of fruit so that its seeds are sent away by animals.

Maybe you've got some birds, you've got some other animals eating the fruit.

They go away somewhere, when they defecate, the seeds come out in their faeces and the plant gets planted in a completely different place.

So again, we don't have young saplings growing underneath the apple tree, which would be much, much bigger and blocking out the light for those saplings.

Okay, let's see if we understood that.

Which of these plants would be most likely to successfully compete for water and minerals? Is it A, a plant that has many broad leaves? B, a plant that has deep, far reaching roots, or C, a plant that has seeds that catch wind and get blown far away? Take five seconds or if you need more time, you can pause and then click play when you're ready to see the answer.

Okay, let's look at the answer.

It is B, a plant that has deep far reaching roots.

So many broad leaves, that's for absorbing sunlight.

Plants that has seeds that catch the window that get blown away, that show plants have plenty of space and aren't growing too close to each other.

Well done if you got that right.

This is our final practise task for today's lesson.

Great job on all your hard work so far, we are nearly there.

So explain why the following plants are likely to compete poorly for resources and less likely to survive and or reproduce.

For each example state what the plant is competing for.

So we've got a plant that grows a small number of leaves with a small surface area, a plant that grows colourless and unscented flowers, and a plant that grows too close to other plants.

So you'll need to pause the video here to give yourself enough time to write down your answers.

Click play when you're ready to see the answers.

Good luck, everyone.

Okay, let's check our answers.

So a plant that grows a small number of leaves with a small surface area.

This plant will compete poorly for light.

It will probably carry out less photosynthesis, so make less glucose it needs to survive and reproduce.

A plant that grows colourless and unscented leaves, flowers.

This plant will compete poorly for pollinators, like birds, bats or bees.

Pollinators will be less likely to visit these plants, so will not transfer pollen to or from them which is necessary for plant reproduction.

Okay, and finally, a plant that grows too close to other plants.

So this plant is more likely to be growing in the shadow of other plants.

This means that it may get less light for photosynthesis, so it may produce less glucose.

Glucose is necessary for the plant to survive and reproduce.

This plant is also less likely to have enough space for its roots.

This means that it's less likely to get all the water and minerals it needs to grow, so it'll be less likely to survive and reproduce.

Great job if you got that right.

Well done on today's lesson on competition.

Let's summarise what we've learned now to make it more likely for us to remember it.

The resources in each habitat are limited.

Living organisms are in competition for these limited resources to enable them to survive and reproduce.

Animals have a variety of adaptations that give them an advantage in the competition for food, water, shelter and mates.

Plants have a variety of adaptations that give them an advantage in the competition for water, space, light, minerals, pollinators and seed dispersers.

The fittest or best adapted organisms are more likely to compete successfully, survive and reproduce.

Again, fantastic work today.

Take a well-earned break now and I'll see you again for our next lesson.