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What's the Use of a Horse's Tail? (scientificamerican.com)
47 points by extraterra on Oct 18, 2018 | hide | past | favorite | 40 comments



Well. I had to read the entire article to see if I was missing something, but my answer is no.

The answer to the question as presented in the headline is more or less obvious for everyone who spent significant time around horses and cows: it keeps insects away. (It might also tell you something about the mood of a horse, less so with cows IMO. Small calves and lambs however will wiggle their tail when drinking milk, either because of some kind of enthusiasm or I've also heard to make sure their mother can smell that they are hers. Sidenote: IIRC lambs who try to steal milk will typically position themselves with the tail away from the head of the eve they are stealing from while lambs that are with their own mother will typically stand parallel to their mother, possibly so she can verify them.)

Then there is the question about the pendulum speed, why do horses swing their tails so much faster.

Well a simpler explanation might be because: 1. Tails arent ideal pendulums and 2.) To get enough speed to cover the top of their backs.

I'm no lawyer or startup founder or cryptographer so often I cannot point out if an article is wrong but I did grow up an a farm and I've earned my first money as a farm hand until I was about 20 and I also have some months in farming school so today it feels like I had something to share :-P


My opinion: long mammals like cows, horses, camels, etc can't reach their behinds with their limbs. They can use their head (especially when the tail doesn't reach the fronter part of the behind), but it's not efficient because their head is heavy (and they're heavy animals in general) and has more inertia. Therefore, a tail is their swift efficient defense for the behind.

By contrast, smaller mammals like cats, dogs, rats, etc, don't use their tails to deter insect, because they can easily jump, move quickly, or smash their head into their body, because they are much lighter.

Now, this makes me wonder, why do cats and dogs have tails. Maybe im the case of cats it is for equilibrium, but dogs? I think dogs use tails to show people when they're excited :)


Look at what the cat's tail does when it leaps through the air, or the dogs tail when turning a corner at high speed, and it will become clear. It's for balance and agility.

Greyhounds and Cheetahs naturally have fairly long tails.


Can we call a greyhound's tail natural, if it has been bred for purpose by people?


I would as they where bread for speed not looks, with the tail evolving based on selection pressure.


Can you call any domesticated animal natural?


Sure, it's not a terrible stretch. An external force (us) encouraged their shaping through selective pressure. We are from the environment, the same as a rift valley or other long term environmental impact, for domesticated animals. As far as I know little to none current domestication uses fully manipulative method like CRISPR.

That we semantically look at our own involvement as somehow different on outcome isn't really the intent of artifice, I think. Rather that humans, individually and collectively, modify the environment to suit their needs.

I'm not really looking to argue the point, but interested in hearing other's thoughts on this.


It’s a legitimate question but it's a slippery slope. A wild horse can be domesticated, is it natural? Donkeys, and camels too, even birds like parrots and raptors can be trained to do work and be subservient to humans.

If the question is learned behavioral domestication vs bred genetic domestication... Is a banana natural? Apples oranges grains, virtually every verity of produce at the store has been ’domesticated’. Are they natural?

Humans have been bred for group behavior, language and manual (slave) labor by means of evolutionary pressure and natural selection. Are we unnatural?

Pretty sure ‘natural’ is not the delineation we want to use


Do not conflate taming/training (of an individual) with domestication (of a species). Very different things.


I saw a lemur (in a zoo) without a tail once — it couldn't jump.


It the case of labrador retrievers, those without a tail have an extremely difficult time swimming, whereas those with a tail used them to provide propulsion and steering.


The tail in dogs is fairly important for communication (especially with other dogs - intraspecific communication), as it can indicate many different emotional states, not only excitement. See for example https://www.mdpi.com/2076-2615/8/8/131/pdf https://www.dogways.info/how-dogs-communicate and https://www.psychologytoday.com/us/blog/canine-corner/201112...

This is another reason why cutting the tail is wrong - besides the fact that it's cruel (it's almost incredible now, but it was common a few years ago, and it is still practiced in some countries).


Showing someone (or another dog) that you're excited or scared ("tail between his legs") is a very potent social mechanism I think. I don't think it adds much to the motor skills of the dog, besides maybe giving it a tool to keep flies and insects away from the ol' pooper.


Watch something like a greyhound or German Shepherd at full throttle and you might reassess your view about whether it adds to motor skills. It seems to be a very active part of a full speed sprint.

It's also a very subtle tool for social interaction as you note - the difference between tail wagging whilst up, horizontal and down, or wagging just the tip and so on. There's quite a lot of complexity hiding there.


Anatomical features often serve multiple purposes. Scent glands in many animals are evolved out of pre-existing features. We talk and chew with our mouths. Etc.


To put it more bluntly, the obvious difference is that cats and dogs can lick their private parts. Cows and horses can't perform the same level of personal hygiene while also providing more surface area for insects to invade.

I wonder whether this is not really more about infestations than bites.


Horses tend to kick if they're trying to get at something behind them.

According to a quick internet search, dogs have tails for the same reason as cats, to help with balance and inertia when running.


you're right, they do kick. they also can shake their skin.

i was thinking more in terms how people or primates can use their hands or feet to basically reach all parts of the body, while cows/horses cannot to the same degree.


With the prevalence of trails, my guess is there is just some cost to removing the trails, genetically. Some evolutions paid the cost, some didn't. Even among animals that don't really need the tail for anything.


String players probably have a strong opinion on this ;)

Seriously, AFAIK there is no artificial solution for bow strings. The only good material for them is carefully selected tail hair from horses in places with cold climates, like Mongolia.


Synthetic bow hair does exist, but it's rather controversial. My experience with it as a luthier and conservatory trained violist is limited..but it looks/feels/acts like very thin gauge high-tension fishing line.


Tangential - the Norden bombsight in WW2 used blonde hair taken from long haired women as part of the sighting mechanism


I don't know how exactly the strings are produced, but I would imagine that cutting off some tail hair is something different than amputating half of the tail.


> The only good material for them is carefully selected tail hair from horses in places with cold climates, like Mongolia.

Do string players usually try drinking horse blood mixed with fermented horse milk? I only played trumpet, so no idea what’s normal for orchestra culture.


Hey man, are you having a good day?


No I mean that's actually a traditional Mongolian food.[1] I'm saying if you have such a deep relationship with these Mongolian horses (via the bow strings) to the point where they're responsible for how you make your art/living, it wouldn't surprise me if some percentage of string players eventually wanted to go over there and learn more about Mongolia and how these horses live in their native habitat. (And/or just try drinking fermented horse milk at parties or whatever.)

It's not really any different than how most people who are ethnically Norwegian or Swedish are probably eventually going to try lutefisk, not because they expect it to be good but just because it gives context to their identity or whatever.

[1] https://en.wikipedia.org/wiki/Horse_culture_in_Mongolia


No cows in zoos. So the biologists didn't study them.

Because of cow patties, there are always lots of flies in cow pastures.

Anyone who has been in a cow pasture in summer would easily notice that cows use their tails the same way as horses do: to chase away flies.


I use a horse hair hygrometer: https://en.wikipedia.org/wiki/Hygrometer


tl;dr: “Our work shows that a horse’s tail isn’t just an ornament. It’s their main line of defense against biting insects”


That's interesting considering it can really only swat away insects around it's behind and is useless for the rest of the body.


I've noticed that when a fly lands on a horse's front area, the horse will twitch its muscles in that area (sort of like if a fly lands on your are and you jerk your arm to get it off), but in the back area it will swish it's tail. Maybe it can't twitch its muscles in the back area like it can in the front area.


According to the article, the goal is not to hit any insect with the tail but rather to create an air wave that is impossible for insects to navigate.


Based on my of observations of cows while working around them another (or IMO rather, the) primary goal seemed to be to swipe or scare away flies and horse-flies that have already landed.


It's not uncommon to see 2 horses standing next to each other, but facing opposite directions, so that each horse's tail can flick flies away from the other horse's face.


There are some nice soft parts there that aren't protected by the animal's skin


The behind tends to be the smelly end on horses though.


Don't forget they're herd animals. They also protect each other (using their tails) when insects are bad.


At least some animals use their tails to balance when running fast.


Balance?


Its so that you can bite on it to make it go faster.




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