Artificially Evolved

[00:00] We got time. You guys want to do an under-googable?
[00:02] Ooh, we do an under-googables.
[00:16] That was the plan.
[00:17] Super excited.
[00:18] You told us we had to.
[00:20] We said we signed up for it.
[00:25] In the end, it's going to be better and more true than Google can give you.
[00:31] I was thinking about this the other day, and this is probably obvious to you, the doctor,
[00:37] but I don't know the answer to it.
[00:40] Why do dogs' tails wag?
[00:44] Hmm.
[00:46] Good question.
[00:47] I've got a wonderful dog, Winnie, who is just a sweet, sweet girl,
[00:54] and she occasionally is very angry.
[00:58] But I would say most of the time, her tail wags all the time.
[01:04] And when she's happy, when she's just chilling, she's just wagging that tail.
[01:11] It seems to go faster when she's happy, and it tends to go down when she's upset.
[01:18] And so I'm wondering if it's like an evolutionary thing, whether she's talking to other dogs.
[01:23] You know, I don't know whether it's a...
[01:28] I don't know. I don't know.
[01:30] Well, so that part I can tell you. For sure, she's talking to other dogs.
[01:33] And humans, for that matter.
[01:35] Right, yeah.
[01:36] So it's a form of nonverbal communication, right?
[01:40] So body posture is a common way that animals signal to one another what's going on.
[01:48] You know, you show your teeth to show that you're angry and try to scare another animal away.
[01:56] Or, you know, if you're fighting for dominance in the pack or whatever.
[02:02] And then the wagging of the tail indicates excitement.
[02:08] Dogs will also tuck their tails if they're...
[02:14] We interpret it as shame, but that's not right.
[02:17] But they're showing weakness, basically, or subordinates, right?
[02:21] Yeah, so that's where it comes from.
[02:25] You know.
[02:27] You're right, I don't.
[02:31] Well, okay, so I guess I understand that, of course.
[02:34] I mean, I guess my question was larger than that, which is...
[02:41] So we've talked evolutionarily about why tails exist, right?
[02:48] So for squirrels and cats, it's balance.
[02:52] And for bunnies and deer, it's to throw off predators.
[02:59] But dogs have a tail that doesn't seem to do any of those things.
[03:06] And so is it just to non-verbally speak, and that's why it exists?
[03:13] I'm sure that they use it for balance when they run and do things as well.
[03:20] Yeah.
[03:21] I mean, there's no reason that it wouldn't help.
[03:27] It helps create a larger center of gravity for you, right?
[03:34] It probably depends a little bit upon the animal.
[03:37] It's like another possible thing.
[03:40] Horses definitely flatten swatting flies with those things.
[03:46] Maybe there's at least some part of it that has to do with hygiene.
[03:56] Potentially, yeah.
[03:58] It wouldn't be for swatting flies.
[04:03] Well, no.
[04:04] I mean, so dogs come from wolves, which are from the tundra, basically.
[04:10] So it's not swatting flies, I don't think.
[04:13] But you can imagine maybe it's another thing to keep them warm
[04:19] when they curl up and wrap their tail around.
[04:22] I mean, I've lived in Minnesota, and there are serious insects up there.
[04:27] Oh, OK.
[04:28] It's true.
[04:29] Oh, yeah.
[04:30] It's true.
[04:33] Oh, yeah.
[04:34] It's summertime.
[04:35] I forgot about summertime.
[04:36] Summertime.
[04:37] And it's all flies.
[04:38] Yeah, you guys do have those biting flies up there.
[04:41] So you get a week and a half of spring, and then it's just fly season.
[04:49] Yeah.
[04:50] That's brutal.
[04:51] OK.
[04:54] So you've shifted the conversation from why do dogs wag their tails?
[05:00] But also, I guess, why do the dogs have tails in general?
[05:03] Why do they exist?
[05:04] Why do they have tails?
[05:05] But my guess would be it's a balanced thing.
[05:07] I mean, like, you can imagine if they're in the middle of a hunt
[05:12] or something like that, and they have to make complicated movements
[05:17] that having an extra thing to keep you balanced
[05:20] is definitely going to be useful.
[05:23] I mean, like...
[05:24] The ESPN stuff, at least these dogs...
[05:27] Because I have, like, 16 TVs.
[05:29] So ESPN2 plays, like, dog stuff all the time, like, races.
[05:34] They, like, jump into pools or they run the gauntlet or whatever.
[05:38] And it's like people will come to watch a game,
[05:41] and all they want to do is watch the dogs.
[05:44] It's amazing.
[05:45] These dogs are amazing.
[05:46] And I suppose if you're running at that speed
[05:51] or flying through the air, you do have to spin your tail.
[05:56] I guess that does make sense to me.
[05:59] Yeah, like, cats have tails for that reason, right?
[06:02] Right, but dogs don't just do the kind of leaping that cats do, I guess.
[06:06] That's what I was thinking.
[06:08] I think you're selling dogs short, but...
[06:13] Not your dogs?
[06:16] I'm trying to have them not leap over the fence,
[06:20] so should I just cut off their tail?
[06:23] I bet you would see them miss for a while,
[06:28] until they adjusted, figured out their new center of gravity.
[06:33] So this is a social thing, the wag of the tail.
[06:37] Dogs are group animals.
[06:40] They're pack animals.
[06:42] And that's the way they speak to each other.
[06:45] We talked about social yawning and all that stuff.
[06:48] It just goes into that phase.
[06:51] Mm-hmm.
[06:52] Okay.
[06:53] All right.
[06:54] I guess it wasn't that complicated.
[06:56] They don't have words.
[06:57] They're so pervasive amongst four-legged creatures.
[07:00] Yeah.
[07:01] Yeah, I just feel like in general,
[07:04] dog tails seem less useful than most tails.
[07:08] I mean, reptile tails don't seem super useful either, but...
[07:12] Well, so you got to remember, when you're talking about dogs,
[07:16] you're also talking about an artificially evolved species.
[07:21] Right.
[07:22] Right.
[07:23] Which is no longer about evolution.
[07:25] Right, exactly.
[07:26] Right.
[07:27] And so you got to go back to the nearest common ancestor,
[07:31] the wolf, and think about what is a tail needed for in a wolf.
[07:36] Okay.
[07:37] Because there are certainly dog breeds that don't have tails,
[07:40] or have stubby tails, or certainly don't need a tail.
[07:45] But hunting dogs, they oftentimes crop the tails,
[07:48] so that they don't rattle the brush when they're pointing to it.
[07:53] Harper, do you remember this?
[07:54] I think we talked about this in college.
[07:56] There was some study they did where they put wolves in cages,
[08:02] and they put domesticated dogs in cages.
[08:06] And both the domesticated dogs and the wolves
[08:11] would get out of their cages at a similar rate,
[08:15] but the wolves figured it out on their own,
[08:18] and the domesticated dogs manipulated humans to get out.
[08:23] Yeah, that's about right.
[08:24] So wolves could unlock stuff and get out or sneak out,
[08:28] and dogs would just pretend to be sick or be real happy
[08:31] or whatever and run past them.
[08:32] They'd just look at their human until they break.
[08:35] Yeah.
[08:36] And literally throw the puppy dog eyes at them.
[08:38] I wonder if the tails, as you talk about this evolutionarily,
[08:45] we're actually taking evolution out of it by breeding these dogs,
[08:51] but the stuff that continues to exist,
[08:53] which is wagging tails actually manipulates humans better?
[08:59] I don't know.
[09:00] It's just a thought process.
[09:04] Well, I mean, it makes sense at some level, right?
[09:06] Like if you have a dog that you can read what their state is,
[09:12] you can handle them better, right?
[09:14] Sure.
[09:15] But sometimes they're lying, and they're just going to run past you,
[09:19] get out of the gate.
[09:23] Yeah.
[09:24] They just want to treat.
[09:28] That's true.
[09:29] They always just want to treat.
[09:31] Right.
[09:32] Yeah.
[09:33] So what I'm reading is dogs...
[09:35] Yeah, it's a balanced thing.
[09:37] Okay.
[09:39] Just like squirrels and cats.
[09:42] Also, potential...
[09:43] They do climb things, and they go over rocky things and stuff like that.
[09:49] Also, some body temperature regulation function, maybe.
[09:53] There are...
[09:54] Just like the nose and the tongue.
[09:56] There's a network of blood vessels.
[10:00] Okay.
[10:03] Dogs are really good at regulating temperature,
[10:05] apparently, is what we've learned.
[10:07] Nose and tongue and tail at this point.
[10:10] They don't act like a rudder when they swim.
[10:13] I forgot about swimming.
[10:14] That makes a lot of sense.
[10:16] Dogs swim.
[10:26] But do they swim enough to...
[10:27] Oh, again, right.
[10:28] We're out of evolution, I forgot.
[10:35] They didn't grow up...
[10:37] Dogs didn't grow up as a sea creature, you know?
[10:41] I don't know if really that works, evolution.
[10:44] I mean, no more than the rest of us, I suppose.
[10:49] Right.
[10:50] Yeah.
[10:58] And it's wagging as a communication thing.
[11:01] And dogs that don't have tails, they do seem to get by just fine.
[11:07] But they still wiggle their little butts.
[11:09] They do wiggle their butts.
[11:13] Interestingly, so, yeah, sometimes wagging can be like,
[11:17] I'm happy, I'm relaxed or whatever.
[11:22] But it can also be stressed or anxious dogs will wag.
[11:27] And there was a study published in Current Biology in 2013 that...
[11:34] ...indicated that...
[11:39] So they can...
[11:40] They can...
[11:41] They can preferentially wag on the left or the right side of their body.
[11:45] So that kind of tilts or whatever.
[11:48] And depending on which side they're doing it on is an indicator of, you know,
[11:53] that the happy, relaxed versus stressed and anxious wags.
[11:57] So you have to know which side of your dog's butt is happy and what side is anxious?
[12:02] Yeah, but it's consistent, I guess.
[12:04] So, like, if a dog is wagging his tail, more on the right side is more relaxed.
[12:13] And when he's wagging on the left side, it could be more alert, stressed or anxious.
[12:18] What if he's right-handed?
[12:21] Oh, good question. I don't know. Right pod?
[12:24] Right pod?
[12:25] Does it all switch? Yeah, I don't know.
[12:32] I mean, you know, a left pod dog is probably, you know...
[12:36] ...brain's kind of broken.
[12:41] Shout out to Joey.