Cheetah vs Greyhound | World's Fastest Dog In Super Slow Motion | Slo Mo #29 | Earth Unplugged

So YouTube, we couldn't help but notice our first cat vs dog slow-mo video kind of stirred a few of you up. So it's time for cat vs dog round two and it's going to be awesome. So mate today's slow-mo is all about speed and let's face it, the cat's already won. Kind of don't want to agree with you on that one, but I'm going to have to, you're absolutely right. Yeah, fastest land animal, the cheetah. I mean the BBC has filmed some great cheetah footage in the past and you can just see why they're such speed demons. So what's the key behind why they're so fast then? Well they've got this really flexible spine which gives them a massive gait, really spreads out their legs and they've got these incredibly powerful back leg muscles to really drive them forward. They've got these semi-retractable claws, so basically their claws are partly out all the time, which is like runner's spikes, just giving them excellent grip and they're just incredible animals, really streamlined, very powerful animals. Ok man, so cheetahs are pretty cool, but how about getting the greyhound, the fastest dog in the world, get that in slow-mo. So we've got two dogs today, Sitty and Sweep, who are going to race for us and we've got two so that one of them can have a rest while the other one's racing. They've just got such big powerful legs, I can't get over it. With the aid of the vampire Batmobile we should really be able to get some awesome shots of these guys in motion. We'll shoot this on a relatively long lens, just so we can keep a bit of distance from the dogs. So quick. So we're about to go for the first run. You're not going to get away from me. Got him. I'm really pleased we got the beginning of that, that's great. Did you see that mud flying? Yeah, and that was off the front feet. I would have expected it off the back, wouldn't you? Really dug in. It really stretches out that. It's so like a cheetah. They run in a style called rotary gallop, which is where their feet basically land in a circular position as they go around. It's that front left, front right, back right, back left. So it's that circular rotary gallop we were talking about. And as you can really see there's two flight phases, so when their feet are off the ground they're either fully extended or tucked up to the body, just like a cheetah. That was pretty quick, Duncan. What kind of speeds were we clocking there? Because we've just a bit overtaken him. Yeah, he's certainly doing 43 plus miles an hour. That's pretty impressive. Without a doubt. So a cheetah's faster than a greyhound, why is that? Yeah, well to be honest, to look at that it's not all that clear, because they're running in a really similar style. But basically some researchers at the Royal Veterinary College in London discovered that greyhounds aren't very good at increasing the frequency of their stride, whereas cheetahs are really good at swinging their legs forward and just building it up and up and up. That was awesome, but now let's try for a head on shot. So I think we've done the dog some justice today. I think you have, I think she deserves her lie down. Yeah, definitely. So the debate still rages on, cats versus dogs, what do you think? Don't forget to like and subscribe and stay tuned for more on Earth Unplugged.