Why didn't animals evolve wheels?

[Tero]

Because there was need. They are very good at being sharks.

[Seth]

Because there was need. They are very good at being sharks.

They'd be better sharks with big brains and arms, after all that's what we have, and we're better than sharks...Oh, and dolphins too.

[JimC]

I wanna know why, in 40 million years, sharks haven't evolved either arms or advanced brains.

Simply, they can excel in their ecological niche without requiring either. In terms of arms, some bottom dwelling sharks have developed a pair of fins on which they appear to walk over the bottom, possibly gaining some information via touch, but that seems to have been the limit.
As well as not needing brains to be extremely successful in their niche, I suspect that shark brains have limited scope for evolutionary development without having proceeded through the various changes that lead another group of ancient fish in the end to becoming tetrapods and eventually mammals. Dolphins re-entered the water after a long period of evolutionary development in much more varied environments than sharks, bringing their large mammalian brains back to the water in the process.

[Sean Hayden]

...

[Xamonas Chegwé]

Because there was need. They are very good at being sharks.

They'd be better sharks with big brains and arms, after all that's what we have, and we're better than sharks...Oh, and dolphins too.

There's a trade-off. A bigger brain requires a bigger, heavier skull; longer developmental time (ie. learning) for infants and hence a greater period of dependence upon its parents; and changes to blood supply, musculature, etc. That simply wouldn't happen evolutionarily unless in every generation the disadvantages at very least did not outweigh the advantages and make the organism less successful in terms of survival and breeding. That's how evolution works. Thankfully, it's also the reason sharks have yet to evolve jet-flippers and laser-eyes. When they do, we're fucked!

[Hermit]

Because there was need. They are very good at being sharks.

...we're better than sharks

Not when you encounter them in their environment. When you try to kick a great white shark as it approaches you at 40 kilometres an hour with your o so superior leg or punch them with your o so superior arm, all guided by your o so superior brain, you'll soon find out exactly how superior your arms, legs and brains are compared to its primitive stage of development.

[mistermack]

I wanna know why, in 40 million years, sharks haven't evolved either arms or advanced brains.

You betray your lack of understanding of evolution and how it works.
Evolution doesn't start with a goal, and work towards it. So to question why something hasn't evolved a feature is assuming that evolution KNOWS that a feature is a desirable thing to have.
Evolution knows nothing.

A designer god might know that a shark could do better, if it had a big brain like ours. But evolution just blunders blindly on, producing variation within species, and whatever variety survives and breeds the best is what gets to reproduce.

With humans, there is a big price to be paid for having a big brain. We take about fifteen years before we become independent. That's because a big brain takes a long time to grow and a long time to mature. And it uses a lot of energy as well.
A shark is independent the day it's born, and can survive on a lot less food, pound for pound, than we can.
So growing a bigger brain might make it slightly less successful, in the short term, and it's the short term that counts, in evolution.

[rainbow]

It wasn't part of the Creator's plan.

[Brian Peacock]

Wheels need a relatively flat and expansiv surface to be effective. Not a lot of the the natural world is flat so any wheeled animal would also have to evolve the equivalent of tires and suspension, and only then if the intermediate stages between the wheeled animal and their non-wheeled ancestor offered tolerable survivability benefits. Then there's the energy transfer problem - how to drive a continuously turning wheel with enough force to move x amount of body-weight, so the creatures would also need some sort of drive train assembly from power source though some sort of evolved gearing system to thee wheel. The gearing system needs to be in place first before any further possible evolutionary experimentation with wheels could even begin let alone proceed. Although all this points to the fact that things evolve blindly over time with no desired end point or design aspirations it's interesting to note that Mamma Nature has put in a bit of R&D time into tooling up for gearing...

[Seth]

Because there was need. They are very good at being sharks.

...we're better than sharks

Not when you encounter them in their environment. When you try to kick a great white shark as it approaches you at 40 kilometres an hour with your o so superior leg or punch them with your o so superior arm, all guided by your o so superior brain, you'll soon find out exactly how superior your arms, legs and brains are compared to its primitive stage of development.

But why aren't they land sharks with legs and everything? We grew legs and arms and big brains which made us the apex organism on the planet, so why doesn't every other creature follow that same plan? Sharks have remained the same for 40 million years, which seems to defy even the notion of accidental genetic changes of beneficial value. After all, dolphins are smarter than sharks and they evolved that way, so why haven't sharks likewise evolved?

[Seth]

I wanna know why, in 40 million years, sharks haven't evolved either arms or advanced brains.

You betray your lack of understanding of evolution and how it works.
Evolution doesn't start with a goal, and work towards it. So to question why something hasn't evolved a feature is assuming that evolution KNOWS that a feature is a desirable thing to have.
Evolution knows nothing.

But evolution created human beings and everything we are today, and yet sharks haven't changed substantially in 40 million years. Why not?

A designer god might know that a shark could do better, if it had a big brain like ours. But evolution just blunders blindly on, producing variation within species, and whatever variety survives and breeds the best is what gets to reproduce.

With humans, there is a big price to be paid for having a big brain. We take about fifteen years before we become independent. That's because a big brain takes a long time to grow and a long time to mature. And it uses a lot of energy as well.
A shark is independent the day it's born, and can survive on a lot less food, pound for pound, than we can.
So growing a bigger brain might make it slightly less successful, in the short term, and it's the short term that counts, in evolution.

So why aren't dolphins like sharks. Or sharks like dolphins? Why are there elk and deer, wolves and coyotes? Why is there 40 million year old species differentiation? Why haven't all creatures evolved towards an organism that is in all ways superior to all other forms of life in all environments?

[Seth]

Wheels need a relatively flat and expansiv surface to be effective. Not a lot of the the natural world is flat so any wheeled animal would also have to evolve the equivalent of tires and suspension, and only then if the intermediate stages between the wheeled animal and their non-wheeled ancestor offered tolerable survivability benefits. Then there's the energy transfer problem - how to drive a continuously turning wheel with enough force to move x amount of body-weight, so the creatures would also need some sort of drive train assembly from power source though some sort of evolved gearing system to thee wheel. The gearing system needs to be in place first before any further possible evolutionary experimentation with wheels could even begin let alone proceed. Although all this points to the fact that things evolve blindly over time with no desired end point or design aspirations it's interesting to note that Mamma Nature has put in a bit of R&D time into tooling up for gearing...

There was a science fiction story I read about a planet that was essentially one smooth ball where the creatures evolved wheels and sails for moving about.

[mistermack]

But evolution created human beings and everything we are today, and yet sharks haven't changed substantially in 40 million years. Why not?

You are making assumptions, based on very little knowledge of evolution. You still seem to have this feeling that evolution has some sort of goal, to produce some super being. It's not like that at all.
Evolution is a random, haphazard process. It doesn't matter if it produces change, or no change. The majority of species went extinct. Do you question that? Those that exist now were basically the lucky ones, which had just enough of an edge to survive. Not always by constantly changing. Sometimes a design reaches a point where it doesn't get any better. Like the bicycle. While computers have changed out of all recognition, the bicycle is still pretty much what it was sixty years ago.
Having said all that, the shark has produced the closely related rays. Manta rays and sharks. Not changed substantially?
Just because one branch develops in a different way, it doesn't mean that others can't stay the same. If it works, it will reproduce.

So why aren't dolphins like sharks. Or sharks like dolphins? Why are there elk and deer, wolves and coyotes? Why is there 40 million year old species differentiation? Why haven't all creatures evolved towards an organism that is in all ways superior to all other forms of life in all environments?

You really do need to do some reading. No form of life is superior to other forms. If it's alive, after four and a half billion years, it's incredibly successful, as were all of it's ancestors.
A human isn't superior to an ant in evolutionary terms.
A lion isn't superior to a wildebeest, or a hyena. They all get by, just about.

Why don't you read up on it a bit, instead of wasting your breath on everlasting gun posts? Evolution is the most interesting thing I've ever discovered, and you never stop learning, there is so much to it.
You'll find better answers than I can give, and all the evidence you could wish for.

And if you want the above questions answered fully, read up on how and why evolution is geared to produce variety. It's a subject all on it's own, and well worth reading. You can't answer it in one post on a forum.

[Brian Peacock]

I wanna know why, in 40 million years, sharks haven't evolved either arms or advanced brains.

You betray your lack of understanding of evolution and how it works.
Evolution doesn't start with a goal, and work towards it. So to question why something hasn't evolved a feature is assuming that evolution KNOWS that a feature is a desirable thing to have.
Evolution knows nothing.

But evolution created human beings and everything we are today, and yet sharks haven't changed substantially in 40 million years. Why not?

A designer god might know that a shark could do better, if it had a big brain like ours. But evolution just blunders blindly on, producing variation within species, and whatever variety survives and breeds the best is what gets to reproduce.

With humans, there is a big price to be paid for having a big brain. We take about fifteen years before we become independent. That's because a big brain takes a long time to grow and a long time to mature. And it uses a lot of energy as well.
A shark is independent the day it's born, and can survive on a lot less food, pound for pound, than we can.
So growing a bigger brain might make it slightly less successful, in the short term, and it's the short term that counts, in evolution.

So why aren't dolphins like sharks. Or sharks like dolphins? Why are there elk and deer, wolves and coyotes? Why is there 40 million year old species differentiation? Why haven't all creatures evolved towards an organism that is in all ways superior to all other forms of life in all environments?

Just in case you're not being rhetorical, the shark is perfectly adapted for its niche - it doesn't have to be any smarter than it is to be the consummate lone apex predator that it is. Orcas and dolphins on the other hand are social mammals which hunt through communication and cooperation, so it seems reasonable to suppose that animals like this probably benefit from enough smarts to develop a theory of mind and a communication schema by which they can relate to other pod members and pool information, and where developing more smarts significantly enhances survivability over time within a particular niche. Cali's the one to ask really. Him and the fishes go back a long way.

[Jason]

Ecological niches.

Also, re: wheels, 'natural' terrain is probably far too uneven to make wheels more viable than limbs - walking is probably a lot more efficient than generating enough torque to roll over a little pebble.