I texted this clip to my wife who wanted proof. I wasn't doing anything stupid on a recent trip to the bahamas. Now, if you're wondering what my feet are doing in shark-infested waters with a bucket of blood 20 miles away from any land. Well, that comes down to a conversation i had with my friends at the discovery channel six months ago.

They told me shark week is coming up and they want to know what i would do if they could put me in the middle of the ocean on a boat surrounded by sharks. For as long as i can remember, i've always wanted to test if sharks can really smell a drop of blood in the water from a mile away. Now, before you say, mythbusters already did this um, they kind of did this, as you can see to test this, they poked their fingers and then stuck them in a barrel with these tiny, lemon sharks and since they didn't really seem to turn around and look at Their fingers, they said i was busted now i'm friends with both carrie and adam, but i think even they would admit at least in this case the methodology was less than scientifically rigorous. So i came up with a more robust test procedure built some nasa grade hardware.

For the experiment, hopped on a plane and then a speed boat and soon enough, i was 20 miles off shore of the bahamas, dude they're sharks, that's shocked! That's the first time i've ever seen a shark like in the wild, see some science to kick things off. I sat down with my marine biologist shark, diving expert friend, luke tipple, and explain my plan down eventually i plan to test just how far they could smell a single drop of blood in the water, but first i wanted proof that they actually preferred blood over any Other scent so for my first experiment, i plan to put four surfboards in the water equidistant from the back of the boat. Each board would host two liters of a different liquid that we would pump into the ocean over the course of an hour. Then, using a three meter radius around each board as a gauge, we would use drone footage and count how many sharks went over to check out each board.

So this board would be fish oil, which i heard was a general attractant for lots of fish. Then we would have cow's blood here then seawater here as a control to make sure the sharks weren't just interested in the surfboard and then finally urine. I've heard from surfers that a lot of them won't be in their wetsuits because they feel like it's going to attract a shark. I don't know a surfer alive who doesn't pee in their wetsuit.

But yes, it's definitely something that i've heard a lot gon na liberate. Surfers everywhere and we show that it's cool to pee in your website and so after a bit more discussion. Luke was on board for the first of our two experiments. Well, as a firm believer in the scientific method, we'll test it out, and then you dive well depending on the results, i can't pee the deals off, and so with that we started putting the four boards together.

We also started collecting scientific donations from the crew. All right so now it's time to fill these bags. What do you want to do? First, pee or blood yeah? I do, let's do pee? Okay, let's do rock paper scissors for who holds the bucket, who holds it back all right appreciate it. I got ta strategize.

Okay, i know it. I know what it needs to be ready. One two three shoot yeah, damn it. Oh that smells so bad, it's urine whose ever it is they need to hydrate dude.

This is going to be a nightmare. Oh, oh! It's warm! Ah dude you're. Pouring sucks, oh okay, we're good we're good all in the name of science. This is a great time of day to be doing this because we have a lot of sharks.

Looking down here, we got oh three or four lemons on the surface and i can actually see two tigers down on the bottom and that's actually a massive target down there. Huge all right see if you can do a better job pouring the knight in oh, my gosh, oh wow, there's a feeding frenzy. I did not it's not going to jump out of the water okay, so we've got seawater as our control. Fish oil have urine and cow's blood let's so, while luke is bravely swimming, the four surfboards out and anchoring them in place in preparation for the one hour.

Countdown now is a perfect time to explain the cool tech on each board. I designed and built from scratch with my buddy sean hodgins, for this experiment to be robust. All four boards need to start pumping at the exact same time after luke has them in place. That means we need to somehow start the pumps using a radio signal from the boat, so each surfboard has a waterproof receiver box like this.

That also hosts the battery a custom, printed circuit board and two arduinos. Then i have the remote control and as soon as i hit this button, they all start pumping. At the same time, we know each pump is working because the corresponding yellow light is lit up. That's important because they're too far away from the boat to see, if they're functioning properly to pump the blood and pee we're using a peristaltic pump.

This is a perfect choice because it's a totally sterile way to get the blood from the bag to the ocean. Since the blood never touches any sort of valve or something it just, has these rollers that sort of pinch and push the blood through the tubing in a manner that just happens to be similar to a severed artery and so with the boards in place. It was go time, operation, shark, bait, test thing commence, three, two one all four are going. We have confirmation, everything is rolling, the experiment is underway, we'll let them go for an hour.

Just dripping stuff out and uh yeah we'll see what happens. Okay and after 10 minutes, i was really surprised there wasn't a lot of action on any of the boards. So so far it's pretty interesting. I mean we've shown if you have a massive cut and you're bleeding out and there's this many sharks within, like 50 yards of you, that they're kind of like man so like already that's an interesting finding right, you'd think a little bit of blood and there'd be A massive swarm, but that's not the case so far and to be clear, we weren't dealing with small quantities.

Here. The human body contains five liters of blood and after you lose two liters, which is the exact amount we're putting in the water. Then you die about 20 minutes in things were still pretty quiet, especially at the fish oil urine and control boards. But then the blood board started attracting some smaller fish and soon after one or two sharks started taking notice, not a lot of love for my pee.

I don't know why i find that kind of offensive, but i'm just a little hurt. Eventually, with about 15 minutes left things started getting pretty wild over by the blood board. The blood was spread out and made almost like a blood runway. So you have this surreal line of sharks swimming up this enticing blood trail, one after another, only to be super disappointed to find a big piece of styrofoam.

We're almost done three two one. The motors have stopped. Our experiment is done. I'd just like to point out: the bags have been sucked dry, so the engineering part of this experiment worked flawlessly dude.

There was shocks everywhere. Are you serious yeah? No two super pissed off tigers, and so now it's time to go in and review the footage and get a final tally for each board. And what we found was that four sharks went to check out the fish oil. Then zero sharks went to check out both the control and the urine, and then the blood board had a direct visit from a whopping 41 sharks, and so now that we debunked some surfing myths about urine and proved that sharks certainly had a strong preference for blood.

Over anything we tested, the real question was just how much blood is interesting to them, and there was one part of the experimental design that was really nagging at me, because that was cow's blood right. That was cow's blood. You want to do human blood. I want to stray human blood.

We've got at least 10 living breathing blood bags around here. It's worth noting not everyone was as stoked as luke, and i about this idea, yeah and then just draw it. We'll just have fresh blood, just mainline it and put it in the water. Why not? Would you be down i'd, be down main dog? What are you recording? Look at me, man.

You have all the pee you so luke made some calls and soon enough we had an amazing certified bahamian phlebotomist on board, i'm like oh, i'm, totally cool. As i like pop the ball, and after some generosity from the camera crew and even captain scotty. We had four bulging bags of human blood for our second experiment. This is my actual blood we're gon na see.

If sharks have a taste for it and uh, if they do, i probably won't go free, diving with them. For the second experiment, we had three boards again, we placed the control in the middle. The board over here would pump the human blood slowly at one drop a minute and then on the other side, this board would pump the blood fast on average one drop every four seconds. We were able to do that because another cool feature for the boxes we built was that by turning this knob, you can control the flow rate.

So over time they can pump out different amounts and because sometimes we all have to step up and just do our part, while luke once again risked his life by placing the three boards, i prepared to push a button. Three two one all right. All of them are uh pumping and good to go now the clock's just ticking. We have like 55 more minutes to go we'll see if the sharks notice it one drop of human blood.

Every four seconds may sound like a lot, and it certainly is, but it's also important to note that's 40 times less than the first experiment, where we saw so much activity in this case halfway into experiment number two, even though there were tons of sharks still in The area the boards themselves were pretty quiet, we'll have to see when we look at the footage afterwards, but so far it looks like the answer is no five, four three two one experiment's over and so after the full hour we brought in the boards and once Again reviewed the footage to see that, over the course of an hour, zero sharks checked out the control board, zero checked out the slow blood pumping board and exactly zero sharks checked out the fast one. So this was by no means a perfect experiment, but i think it's safe to qualitatively say that if no sharks came to check out 15 drops of human blood a minute in the middle of shark-infested waters, you're, probably gon na be okay with a small scrape. I mean there certainly won't be some kind of feeding frenzy with a single drop of blood from all sharks within a mile. Now that i had some first-hand data to put my mind at ease, i was willing to try diving with the sharks without a cage, but i had one final experiment.

I had a theory that if we secured a 360 camera to the front of a hand spear and then shot it near some sharks, we could create the world's first really cool matrix-like underwater bullet time effect. So i suited up and got in, and my theory proved correct on the bullet time handsphere, because, as you can see, that footage turned out really cool. Okay, i'm gon na die. That was amazing man.

We got them in like a feeding president yeah and there's like six of them all around us, and i lived, i mean this is shaping up to be a great day. What i'll take home from this shoot is just more evidence of the amazing animal that sharks are, but also the ability to point people in a specific direction to say: hey your thoughts about them are a little overblown. This experience definitely changed my perception on sharks. I would say i respect them more after seeing their raw power up close, but at the same time there's less of that fear that comes from ignorance.

On top of all that i didn't die, you.