When it comes to teeth, do most people have fairly straight teeth or are most teeth crooked in one way or another? Without braces, what would the population look like? Why is it that humans have problematic teeth (crooked, crowded, too far apart)? This isn’t beneficial to us, so shouldn’t genes for “bad” teeth have been selected against/not appeared at all. I realize that humans with bad teeth have kept on reproducing, passing on these genes and it’s been very difficult to get rid of this, but why are genes for problematic teeth even present?
When it comes to animals in the wild, do they have cavities/teeth problems just as much as humans do or is it a lot less? If it is less, why so? Do animals just put up with the pain or do they have another solution to painful cavities?
First, you are assuming that the poor alignment of teeth is genetic - it may not be. It could very well be primarily developmental, in which case there’s little natural selection can do about it. Second, even if the trait is entirely genetic, it doesn’t matter that the trait is not beneficial, only that it is not detrimental.
Nice, evenly-spaced, white teeth is more of a cosmetic concern than a functional one. Teeth (our teeth, anyway) pretty much just need to cut, tear and/or crush, and even poorly aligned ones (save for certain extremes, of course) can accomplish that much. And as long as they work, unless there is a concentrated effort on the part of potential mates to base their preferences on the crookedness (or lack thereof) of one’s teeth, the trait is unlikely to adversly affect one’s ability to reproduce.
Exactly as they do in the vast majority of the world where braces are not common. I.e., some people have straight teeth and some do not.
Bad teeth - worn, rotted, cavity-ridden, or whatever - are very much due to changes in diet over the millennia. Grit included in agricultural products wear teeth down; sugar in diets rot them. Whatever teeth you see in the world today have little to do with whatever evolution would produce.
I got one right here. Not badly misaligned, but my daughter’s Peke has slightly crooked lower teeth. It happens; most of the time you just don’t notice because animals don’t have those prominent upper front teeth like we do.
As far as whether animals get cavities, yes, they do. Pets, anyway, especially those who eat too much soft food. We had a cat whose canine teeth had to be removed because of infection and gum disease. In nature, carnivores gnaw on bones and such, and their teeth stay a bit cleaner. But if they develop a problem, yes, they just suffer and if the problem is bad enough that they can’t hunt or eat, they die. I’m basing this on TV nature programs, of course, so maybe this isn’t the best source, but it sounds reasonable.
Then you haven’t looked very closely at dogs teeth.
Canine (and feline) dental work is an increasing part of the business of vets nowdays. Partly related to them being mostly pets, rather than working animals, and the kind of stuff we feed them. Plus the fact as pets, many of them are pampered, and the indulgent owners ask vets to fix problems that previously would have been considered natural. Often really mostly cosmetic work – we want our pampered pets to be as beautiful as movie stars. So often owners will request fixes even for dental ‘problems’ that are non-threatening to the animals health.
My mother has an equine dentist who comes by twice a year to check out our horses teeth. But that’s actually functional, since it’s important both for their feeding, and because the teeth & jaw is where the bridle guides a horse.
And don’t say anything about ‘looking a gift horse in the mouth’. At the prices we pay for this, it’s far from a gift!
Bad teeth won’t necessarily be selected against, by the way. As long as the creature can chew, it should be fine. Take my teeth, for example. They’re not properly lined up, but the surfaces have formed in such a way that I can grind my food like a normal person.
both my parents have naturally straight teeth. i don’t. 4 years of braces.
the philly zoo had a tiger (condor) who ended up with root canal in nearly every tooth. he would have died in the wild. the pain from chewing, and breaking teeth would have starved him. he would have had great difficulty in tearing.
turned out it was a genetic thing as his son had the same tooth problems. they didn’t breed him again. he and his son, even with the root canals and crowns, needed to have their food ground up, they had trouble “tearing into” their food.
if you are a rocky fan, i’m told the proposal scene has the tiger (condor) in the backround.
One of the dogs I see every day has crooked teeth. He’s one of those flat-faced toy breeds. I’m told they frequently have poor teeth.
Domestic horses need their teeth floated (rasping off sharp edges) periodically because most horses, like most people, don’t have perfectly aligned teeth. As the portions of teeth that *do * align wear down, the parts that *don’t * align form razor-sharp ridges that can cut into the opposing gum and cheek tissue.
Wild horses either live with this or die from the effects (infection of the abraded tissue, starvation due to being unable to eat). This probably helps weed out animals with misaligned teeth, and increases the number of animals with good teeth that live to reproduce. When this pressure is removed, as in domestic horses that get their teeth done, more animals with poor teeth are able to reproduce.
A lot of this, however, is due to the diet of modern domestic horses. They are generally fed a fairly high-quality (protein rich) feed, 2 or 3 times a day.
Horses are evolved to eat lower quality feed, and pretty much graze continuously. Such grazing tends to keep their teeth in better shape than the typical barn schedule of feeding rich food only a couple times a day.
What is the point of wearing braces anyway? My teeth were somewhat crooked as a kid and I wore braces for 2 years until they become straight. Then I wore a retainer for a year and a half after that, but who wants to wear a retainer for the rest of their life? Once I stopped wearing it, my teeth gradually shifted back to their original crooked position. I don’t see many adults wearing braces or retainers, so I would have to conclude that the population wouldn’t look much different whether they once wore braces or not.
I vaguely remember hearing that having braces can evade a future headache problem because of misaligned jaw or somesuch. Anyone have the dope on such a claim?
I’d also like to point out that wild animals tend not to live so long as those in captivity - so they don’t live long enough to develop problems.
For example - a wild horse might live 5 or 6 years compared to a domestic horse living 15 or even 20. So in the latter case there’s just simply more time in which uneven wear or decay can take place.
Same for dogs (and, by the way, I’ve known a number of dogs with crooked teeth, not all of them flat-faced toy breed). A wild dog might live 2-3 years. A domestic dog 7-10. So the pets have an addition 5 or more years in which to develop decay, tartar, gum disease, break teeth, etc.
In nature, carnivores gnaw on bones and such, and their teeth stay a bit cleaner. But if they develop a problem, yes, they just suffer and if the problem is bad enough that they can’t hunt or eat, they die. I’m basing this on TV nature programs, of course, so maybe this isn’t the best source, but it sounds reasonable.