Brian Clegg

Blood is red because of haemoglobin. So there's substance in the stuff that carries the oxygen around the body. And that haemoglobin does contain iron. And so it's quite easy to get a little bit confused and think, OK, well, iron usually makes things reddish. So rust is iron oxide. It's an iron compound. Mars looks red because there's a lot of iron in the surface.

So we tend to associate iron and redness. But it happens, the reason hemoglobin is red is actually due to the shape of the molecule, the way it interacts with light. It's nothing to do with the fact the iron's in there. So that's one aspect of it. It's not actually caused by the iron. And the other thing is the blue blood thing is not about the color of the blood itself.

So we tend to associate iron and redness. But it happens, the reason hemoglobin is red is actually due to the shape of the molecule, the way it interacts with light. It's nothing to do with the fact the iron's in there. So that's one aspect of it. It's not actually caused by the iron. And the other thing is the blue blood thing is not about the color of the blood itself.

So we tend to associate iron and redness. But it happens, the reason hemoglobin is red is actually due to the shape of the molecule, the way it interacts with light. It's nothing to do with the fact the iron's in there. So that's one aspect of it. It's not actually caused by the iron. And the other thing is the blue blood thing is not about the color of the blood itself.

It's about the way that light interacts with your veins. It's quite separate from the colour of the blood in them. Colour is quite interesting. Sometimes it's caused by a pigment. So sometimes it's caused by the colour of stuff, but sometimes it's structural. So actually the shape of something can change the appearance or the way light interacts with molecules.

It's about the way that light interacts with your veins. It's quite separate from the colour of the blood in them. Colour is quite interesting. Sometimes it's caused by a pigment. So sometimes it's caused by the colour of stuff, but sometimes it's structural. So actually the shape of something can change the appearance or the way light interacts with molecules.

It's about the way that light interacts with your veins. It's quite separate from the colour of the blood in them. Colour is quite interesting. Sometimes it's caused by a pigment. So sometimes it's caused by the colour of stuff, but sometimes it's structural. So actually the shape of something can change the appearance or the way light interacts with molecules.

If you look up at the sky, the sky is blue, but there's no blue colour. pigment in the sky. There's nothing up there that is blue. It's literally the way the light is interacting with the molecules of air. And similarly, when you see the blue veins in your arm, it's not that the blood in them is blue. It's the way the light interacts with the material that makes up the veins.

If you look up at the sky, the sky is blue, but there's no blue colour. pigment in the sky. There's nothing up there that is blue. It's literally the way the light is interacting with the molecules of air. And similarly, when you see the blue veins in your arm, it's not that the blood in them is blue. It's the way the light interacts with the material that makes up the veins.

If you look up at the sky, the sky is blue, but there's no blue colour. pigment in the sky. There's nothing up there that is blue. It's literally the way the light is interacting with the molecules of air. And similarly, when you see the blue veins in your arm, it's not that the blood in them is blue. It's the way the light interacts with the material that makes up the veins.

The reality is that bumblebees don't fly the way you might think. So if you think of a bird flapping its wings, it's fairly obvious what's happening. It's flapping its wings up and down. That pushes the air down, effectively pushes the bird up as it pushes the air down.

The reality is that bumblebees don't fly the way you might think. So if you think of a bird flapping its wings, it's fairly obvious what's happening. It's flapping its wings up and down. That pushes the air down, effectively pushes the bird up as it pushes the air down.

The reality is that bumblebees don't fly the way you might think. So if you think of a bird flapping its wings, it's fairly obvious what's happening. It's flapping its wings up and down. That pushes the air down, effectively pushes the bird up as it pushes the air down.

bumblebees wings move in a much more complicated way they basically almost act a bit like a helicopter in that they have a kind of curved motion and the result of that is they actually generate more lift than you expect from those little wings

bumblebees wings move in a much more complicated way they basically almost act a bit like a helicopter in that they have a kind of curved motion and the result of that is they actually generate more lift than you expect from those little wings

bumblebees wings move in a much more complicated way they basically almost act a bit like a helicopter in that they have a kind of curved motion and the result of that is they actually generate more lift than you expect from those little wings

The other thing about bumblebees actually is they look chunky, you know, compared with an ordinary insect, they look pretty fat, but actually it's still very light. So it isn't as dramatic looking, as dramatic as it actually looks to be. And the fact is there's no problem at all with bumblebee wings supporting bumblebees. In some ways, a more interesting example is kangaroos.

The other thing about bumblebees actually is they look chunky, you know, compared with an ordinary insect, they look pretty fat, but actually it's still very light. So it isn't as dramatic looking, as dramatic as it actually looks to be. And the fact is there's no problem at all with bumblebee wings supporting bumblebees. In some ways, a more interesting example is kangaroos.

The other thing about bumblebees actually is they look chunky, you know, compared with an ordinary insect, they look pretty fat, but actually it's still very light. So it isn't as dramatic looking, as dramatic as it actually looks to be. And the fact is there's no problem at all with bumblebee wings supporting bumblebees. In some ways, a more interesting example is kangaroos.

Of course, it is genuinely true that kangaroos use more energy or appear to use more energy when they bounce along than they consume. They seem to be able to actually give out more energy in their bounces than they've consumed in their food. And the reason for that is it's a bit like the way a rubber ball works. You know, if you drop a rubber ball on the floor, it bounces.