Hello, welcome along to the smartest show in the universe. It's Dan. This is the Fun Kids Science

Midweekly. Bight-sized awesome science. This week, Arlo asks why birds fly. Lacey wonders why

animals have different-shaped eyes. Ronnie is intrigued about what viruses eat. Laura

needs the answer to why we laugh when we're tickled and Harry asks if there are colours that we can't

see. And if we can't, how do we know if they exist? Let's get one on then. This is from Arlo.

How do birds fly? How do birds fly? Well, they fly because of their brilliantly shaped wings, their light bodies, and their strong muscles too.

A bird's wing is curved on top and flatter underneath. It's just like a plane's wing, actually.

It uses exactly the same principles, really. It means the air moves faster above it as it rushes over the curve and slower

beneath. That means there's a lower pressure above the wing because there's less air above it

because it's moving faster than there is below where there's more air and that makes lift

makes a little vacuum on the top which sucks the birds upwards also they flap their wings that

gives them thrust which helps push them through the sky they use their powerful pecks their big

chest muscles to propel them forward they They twist their wings and their tail feathers,

which lets them control direction and speed. And remember, they've got a much better awareness of air

currents all around them through the sky than we do. They can always see air, which helps them

stay up there. They know where the thermals are. That's the hot air that makes them rise.

And it lets them keep floating

without needing to flap their wings. Remember, some birds can't fly. The bigger birds,

penguins, ostriches, they can't fly because, well, there's no need for them to. They are the top,

really, of their food chain where they live. So they don't need to fly after any creature to chase it down.

They don't need to fly away from any animal, so there's no need for them to evolve the need

to fly. And also, ostriches, remember, are massive. They're super fast, really strong as well,

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