103: Mysterious Duck Feet

Speaker 0 00:03 Welcome to brain junk. I'm Amy Barton and I'm trace Kurt and it's time for a brainstorm. So when I was little, my dad would take me to the park and there was a pond and one day I was like, dad, I would really like to pet a duck. And so he walked up and grabbed a duck. It's one of the biggest memories that I have of being a little kid of him holding this very surprised looking duck and getting to pet it. Awesome. And he and I were talking about that the other day and one of the things I was thinking about was the Duck's feet. And especially now that it's winter, I was, and this is something that comes up every time we see ducks on a frozen pond. It's like, why are their feet not freezing? Yeah. Stick into it like the kid in that movie with the pole. Speaker 0 00:49 Right? I mean, why aren't they getting hypothermia? I mean, I go outside with without gloves and my fingers are like super cold. Yes. Well, it turns out that a lot of birds, ducks especially have a very special thing. And their circulatory system, it's called <inaudible> Mira Bali. So if you think about in a human circulatory system, you have veins that go from the heart out to your extremities and then they come back to the heart. So you're circulating that blood will in birds, this Ricci, Mira Bali, imagine arteries woven together like a net. Huh? So that blood coming from the heart, warm blood is passing through a whole bunch of smaller veins and arteries coming back from the feet. Okay. So the warm blood is warming up that cold blood, that super cold blood, that's like standing on the ice. So as it comes back into the body, it's not super cold. Speaker 0 01:47 And then the blood that is getting out to the feet is cooler. So you're losing less heat. Okay. And it's just enough that it keeps the bird's feet from freezing and getting frostbite. Wow. It's not a, you know, it's not this huge flow of blood like it would be any human being that you got all this blood going down to your toes and your toes are getting super cold. In fact, in some ducks there are over 19 branches braided together, exchanging heat. Wow. As it goes down to the feet. Ah. So if their little web toes are already cold and they lose less heat, so the entire duct stays warm. Wow. Don't just wonder who the first scientist who figured this out was and how they're like, Oh, I mean science. Speaker 0 02:35 Well, what's cool is scientists have calculated that in freezing water. So it's 32 degrees Fahrenheit or zero Celsius. Mallard ducks last only 5% of their body heat through their feet. Really? Yeah. So you've got this blood that's getting cooled down as it goes through this network of arteries and then it goes out to those toes and then flip it around all day. Yeah, no problem at all. We do one polar bear pledge and we almost die pretty much. Yeah. And the same system is also used to keep birds and overheated water. Cool. So flamingos can have, I think it was like somewhere in the 70s or more of these braided arterial branches because it's doing the opposite thing. Your feet are super, super hot. Yeah. And as it comes in, it's getting cooled off by the cooler blood in your body and then it's going back. Exactly. Speaker 0 03:25 Wow. That is nifty. It is nifty. And as someone whose fingers get completely numb when they get super cold, I could handle some of this, I think. Oh yeah, yeah. Like you're going to be kind of cold all the time, but never freezing deal high five. I'll take it. Well, but that was a question that somebody had was do they even realize that they're cold? You know, I think about that with my chickens outside. And the thing is if you feel cold or if you are uncomfortable, you would probably try to move out of a situation. But think about those ducks. They're just sitting there on the ice, losing hardly any Pete through their feet. Yeah. They're not dancing around or looking like they wish they were somewhere else. No, they're just chill. Literally. That is amazing. And that's my brainstorm. We're on Facebook and Instagram as brain junk podcast. If you'd like to go look at pictures of duck feet, there might be some on this. Oh yeah, absolutely. And you can find us on Twitter as at my brain junk trace, and I will catch you next time when we share more of everything you never knew you wanted to know, and I guarantee you will not be bored.