Because intelligence isn’t really very important for survival or more generally for evolutionary success. We like to believe that evolution is directed to producing intelligence, but that’s only because it’s our defining feature. Animals did just fine without it for 500+ million years.
Also, it wasn’t just intelligence that got us to where we are today. It would have been useless for dinosaurs to be able to think of domesticating prey animals as a more dependable food supply when they didn’t have opposable thumbs to make corrals.
Not sure if you’re being serious or not, but what makes you think one needs opposable thumbs to make corrals? And some dinosaurs had forelimbs capable of clasping objects.
Thanks for the link, Doughbag! Funny and informative. 
I think there was a breed of dinosaur that had both opposible thumbs and binocular vision and who lived in groups which scientists think might have been on their ay to self awareness. But one will never know unless we find a fossil of one holding a clay pot.
Which brings up the old question that if humans ever became extinct, which animal would rise up and invent the wheel and such?
Assuming the chimps are still around I’d put my money on them, followed by other apes and monkeys. But I wouldn’t rule out animals like beavers either, or even birds. Animals like dogs and wolves are very intelligent but seem highly adapted to their particular abilities and physiology and it’s hard to see the evolutionary pressure driving them in the direction of tool building.
Some theropods had binocular vision, and Bambiraptor is thought to have had opposable digits. However, if any scientists think any dinosaurs may have been on the way to self awareness it’s wild just speculation without any definite basis.
Since land animals had gone hundreds of millions of years without inventing the wheel, I wouldn’t count on it ever happening again. There is nothing in evolutionary history that suggests that human grade intelligence is something that will deterministically arise given enough time.
The OP might want to read The Ancestor’s Tale, by Dawkins, which traces our evolution backwards, and highlights the major points where we diverged from other kinds of animals.
Such a development would be neither predictable nor inevitable. It might happen; it might not.
This is a point that lies at the heart of many a misunderstanding about evolution. Intelligence (and even self awareness, as another poster mentioned here) is simply one adaptive strategy in the game of survival. It’s not the end-goal of evolution.
Intelligence allowed homo sapiens to adapt more easily to changing environmental conditions, so in a way it has been a useful trait. But intelligence itself is not necessarily a good strategy. Look at our closest relatives, the great apes. For all their intelligence, gorillas and other great apes have not done very well compared to other less intelligent mammals. Rats, for example, are probably not as intelligent as chimps or gorillas, but they have shown an ability to adapt into the human urban environment that has made them much more successful in terms of survival and reproduction.
If we take the measure of a species’ success as the actual number of individuals alive, then the most successful is the lowly ant:
Okay, okay, maybe they could have built crude corrals with their mouths, but beyond that they wouldn’t have been able to accomplish much without fine manual dexterity.
There are certain types of ants that farm and herd aphids and mealy bugs as a source of food. Here’s a video. No need for opposable thumbs.
Maybe, maybe not. But no reason that trait couldn’t evolve.
Lots of other animals probably do have self awareness. Hard to know for sure, and to what level, of course. Check out the mirror test.
That’s fascinating in its own right (really cool video), but without hands, let alone opposable thumbs, they can’t do much else.
Of course, but my point was that they would have needed that as well as intelligence to become as technologically advanced as humans are. We didn’t get to the point of going to the moon on intelligence alone. We had to make the tools to get us there.
I dont think it would be a species of great apes since they have evolved into the niche we see them in today. So have almost all other animals. For apes to evolve higher they would have to take some steps back or de-evolve some to put them on a different evolutionary track.
So whatever species rises up and invents the wheel and such is probably right now in the basic stage of simple multi-celled organism which might require a hundred million years to evolve that high.
sorry if the question is unclear, my knowledge on the matter is rudimentary. as it often happens when my mind wonder on matters i don’t fully understand, i’m not exactly sure what my own point was.
anyway, i was picturing some thing without pain receptors, and i wondered how far back you have to go before our ancestors live without experiencing pain. do fish experience pain? we have fingernails. does that mean that, at some point, there must be a creature with prototype hands without nails? which came first? the penis or the vagina? did the first prototype penis fit? was it a square peg in a round hole?
thanks for the replies. i may not be able to contribute much to the discussion but it is always interesting to follow.
you sound like the 2nd graders! the classifiers have spoken, hush 