Would Troodon really have evolved into a humanoid?

Aug 2013
956
Italy
#1
Troodon, often considered to be one of the brainiest of all dinosaurs, unfortunately went the way of his fellow dinos: into extinction.

But what would have happened if his species had survived into the Eocene and beyond?

Would this charming, clever chap really have evolved over time into a humanoid, with the intellectual capacity of Homo Sapiens?

An intriguing theory to this effect exists, and has been given much publicity...
 

Corvidius

Ad Honorem
Jul 2017
2,550
Crows nest
#2
On physical appearance I don't go with Dale Russell's "Dinosauroid" as it is way out of spec for any possible evolutionary development in dinosaurs, far too anthropomorphic and based on thinking that as we are the top of the ladder now, that our bauplan is the only one available for intelligence. We are a convenient shape to sit, and as we don't take up much room horizontally, can make homes and machines we can sit in that are not too big. A house for a dinosaur, even a small one, would need to be big, and any sort of vehicle, problematic with their body shape, but not impossible, just needing more materials and more space.

On intelligence things are better, much better. I'll make one unproven contentious statement to get it out of the way. This is about dolphins. We know they are very intelligent, but there is an element of doubt as too how intelligent they are based on EQ. A few dolphin species, Bottlenoses being the prominent one, are second to us in EQ and have an EQ of 4.4, which is huge compared to the best corvids and apes at about 2.8. But dolphins do not show such a huge advance in intelligence that their EQ would suggest. The big EQ dolphins also just happen to be the ones with the most sophisticated sonar, which do of course need greater intelligence, but I would suspect that most of their extra brains are for sensory purposes, not thinking. Therefore, I would contend that as it seems that the brainiest corvids are more brainy that the brainiest ape, except us, and that the big EQ dolphins don't have a corresponding level of intelligence, that corvids, a maniraptor cousin of troodontids, and even potentially a descendant of basal troodontids, could be the second or equal second most intelligent animal on the planet. And further, that before we evolved, and while dolphins were still evolving, corvids were for a time the most intelligent animal on the planet.

Troodon. Whether they would have evolved high intelligence is of course impossible to say. While bird intelligence can be said to be a consequence of flight, and even the lowliest modern bird has either more brains or no less brains than troodontids, that troodotids do have an EQ the same as some modern birds shows that flight is not the only determining factor in dinosaur intelligence.

If the extinction had never happened, then I don't see any pressing reason why modern avian intelligence would not have evolved to were it is now. But with non avians like troodon any increase in intelligence would be determined by a need for increased intelligence. That the coelurosaur brain was evolving and getting bigger in proportion to the animal shows that there was an evolutionary pressure to increase brain size irrespective of flight, so further increases in brain capacity cannot be ruled out. However, as there is a more than 100 million year gap between the first coelurosaur and the last non avian one, the advance in brain size, except on the branch leading to avialans, was glacial and it needs to be considered if, in the event of there not being an extinction, any further significant progress would have been made in the following 66 million years to today.

However, even without the extinction the Earth would still physically be the same, the same continental drift, the same ice ages and other less damaging meteor strikes. So Dinosaurs would have had a lot of major changes to contend with. Some would have fallen by the wayside, others evolved to cope with the changing conditions. Looking at birds and how they have evolved to occupy the entire planet and cope with extremes of heat and cold, it is reasonable to suppose that at the very least their maniraptor relatives would also have evolved to cope with the large changes to the Earth in the last 66 million years.

Birds and dolphins show that high intelligence is not dependent on having grasping hands, intelligence does not have to have a club, or a gun or a seat or a car, but to reach the Moon, well of course. So if we blinked out of existence tomorrow, I don't expect there will ever be a landing on the Moon by ravens, even in a further 66 million years. But Troodon does have grasping claws, only three, but that's better than none. So if ecological changes drove troodontid evolution to need to develop a large brain, then by fact of their grasping claws, I see no reason why they could not have become more competent tool users than corvids. In fact, by them having a usable hand, that should drive brain power further and an equivalent of the "Dinosauroid" could have evolved, but still as a horizontal biped, not upright, and still no seats, but maybe a rocket to the Moon.

This looks a far better candidate for a high intelligence non avian dinosaur than "Dinosauroid".


"Dinosauroid" for comparison. It is shown alongside it's "ancestor" Stenonychosaurus, which was renamed Troodon, and then this year reverted back to being Stenonychosaurus. Nothing about dinosaurs is simple....
 
Last edited:

Bart Dale

Ad Honorem
Dec 2009
7,095
#3
On physical appearance I don't go with Dale Russell's "Dinosauroid" as it is way out of spec for any possible evolutionary development in dinosaurs, far too anthropomorphic and based on thinking that as we are the top of the ladder now, that our bauplan is the only one available for intelligence. We are a convenient shape to sit, and as we don't take up much room horizontally, can make homes and machines we can sit in that are not too big. A house for a dinosaur, even a small one, would need to be big, and any sort of vehicle, problematic with their body shape, but not impossible, just needing more materials and more space.

On intelligence things are better, much better. I'll make one unproven contentious statement to get it out of the way. This is about dolphins. We know they are very intelligent, but there is an element of doubt as too how intelligent they are based on EQ. A few dolphin species, Bottlenoses being the prominent one, are second to us in EQ and have an EQ of 4.4, which is huge compared to the best corvids and apes at about 2.8. But dolphins do not show such a huge advance in intelligence that their EQ would suggest. The big EQ dolphins also just happen to be the ones with the most sophisticated sonar, which do of course need greater intelligence, but I would suspect that most of their extra brains are for sensory purposes, not thinking. Therefore, I would contend that as it seems that the brainiest corvids are more brainy that the brainiest ape, except us, and that the big EQ dolphins don't have a corresponding level of intelligence, that corvids, a maniraptor cousin of troodontids, and even potentially a descendant of basal troodontids, could be the second or equal second most intelligent animal on the planet. And further, that before we evolved, and while dolphins were still evolving, corvids were for a time the most intelligent animal on the planet.

Troodon. Whether they would have evolved high intelligence is of course impossible to say. While bird intelligence can be said to be a consequence of flight, and even the lowliest modern bird has either more brains or no less brains than troodontids, that troodotids do have an EQ the same as some modern birds shows that flight is not the only determining factor in dinosaur intelligence.

If the extinction had never happened, then I don't see any pressing reason why modern avian intelligence would not have evolved to were it is now. But with non avians like troodon any increase in intelligence would be determined by a need for increased intelligence. That the coelurosaur brain was evolving and getting bigger in proportion to the animal shows that there was an evolutionary pressure to increase brain size irrespective of flight, so further increases in brain capacity cannot be ruled out. However, as there is a more than 100 million year gap between the first coelurosaur and the last non avian one, the advance in brain size, except on the branch leading to avialans, was glacial and it needs to be considered if, in the event of there not being an extinction, any further significant progress would have been made in the following 66 million years to today.

However, even without the extinction the Earth would still physically be the same, the same continental drift, the same ice ages and other less damaging meteor strikes. So Dinosaurs would have had a lot of major changes to contend with. Some would have fallen by the wayside, others evolved to cope with the changing conditions. Looking at birds and how they have evolved to occupy the entire planet and cope with extremes of heat and cold, it is reasonable to suppose that at the very least their maniraptor relatives would also have evolved to cope with the large changes to the Earth in the last 66 million years.

Birds and dolphins show that high intelligence is not dependent on having grasping hands, intelligence does not have to have a club, or a gun or a seat or a car, but to reach the Moon, well of course. So if we blinked out of existence tomorrow, I don't expect there will ever be a landing on the Moon by ravens, even in a further 66 million years. But Troodon does have grasping claws, only three, but that's better than none. So if ecological changes drove troodontid evolution to need to develop a large brain, then by fact of their grasping claws, I see no reason why they could not have become more competent tool users than corvids. In fact, by them having a usable hand, that should drive brain power further and an equivalent of the "Dinosauroid" could have evolved, but still as a horizontal biped, not upright, and still no seats, but maybe a rocket to the Moon.

This looks a far better candidate for a high intelligence non avian dinosaur than "Dinosauroid".


"Dinosauroid" for comparison. It is shown alongside it's "ancestor" Stenonychosaurus, which was renamed Troodon, and then this year reverted back to being Stenonychosaurus. Nothing about dinosaurs is simple....
The picture showing what the hypothetical intelligent dinosaur would have looked like the reveals the fundament flaw in the thinking. It shows a very human like bipedal gait, very unlike the bipedal motion of dinosaurs. To change over from a dinosaur bipedal motion to a human style one would require major evolutionary changes, and I don't see that happening. Human bipedal walking is impossible with a tail, and human ancestors lost their tail before they became bidepal. I don't see the dinosaur evolution proceeding that way.

Moreever, dinosaur bipedal motion will always have pressure to reduce the arm size, because the arms are off the center of gravity. There may be counter evolutionary pressure to retain the arms for specific functions, but in the 150 million years of the dinosaur's reign, the dinosaurs hadn't evolved grasping hands equivalent to humans or even apes, I/am not sure another 65 million years would have made a difference.
 
Last edited:

Corvidius

Ad Honorem
Jul 2017
2,550
Crows nest
#4
The picture showing what the hypothetical intelligent dinosaur would have looked like the reveals the fundament flaw in the thinking. It shows a very human like bipedal gait, very unlike the bipedal motion of dinosaurs. To change over from a dinosaur bipedal motion to a human style one would require major evolutionary changes, and I don't see that happening. Human bipedal walking is impossible with a tail, and human ancestors lost their tail before they became bidepal. I don't see the dinosaur evolution proceeding that way.

Moreever, dinosaur bipedal motion will always have pressure to reduce the arm size, because the arms are off the center of gravity. There may be counter evolutionary pressure to retain the arms for specific functions, but in the 150 million years of the dinosaur's reign, the dinosaurs hadn't evolved grasping hands equivalent to humans or even apes, I/am not sure another 65 million years would have made a difference.
Nobody except those obsessed with "reptilians" took the "Dinosauroid" seriously, not even Russell I think as it was just an exercise in "what if", not serious science. All maniraptors, avian and non avian, had long arms and grasping hands, that's what gives them their name. There was no reduction in their arms and the only problem they had was reduction of the tail in avians, and this was countered by having a slightly more upright stance and drawing the knees forward under the body by changing the angle of the femur, their arms remained as long as ever.

The question of a dinosaur evolving a decent grasping hand like ours is probably the biggest stumbling block of course. The issue I think is of them having only three digits, so would never have the the type of grip that we have. I cannot see the long lost other two digits returning as there was not even a vestigial trace of them remaining. But they could grip of course, and to be a tool maker and user would, as far as their hands go, only need to evolve shorter digits and shorter claws, not beyond the realms of possibility. Corvids make tools, they even make tools to make tools, and just with a bill, so I think that a non avian maniraptor with grasping hands would do even better, even without being able to pronate it's wrists. And this is the next problem for them.

While it would be better for them to have their semilunate carpal joints evolve so that they could pronate their wrists and so have greater flexibility of use, I don't think it is essential, and we go back to corvids making tools with far less flexibility than this imagined evolved non avian maniraptor with at least a grasping hand. For the semilunate carpal to change it would need them to start doing something that directly affected how they use their wrists. They climbed trees and jumped around and eventually flew, but they never swung from branches like an ape because they never needed to. I cannot see what they could do to cause an evolutionary change, but again, we cannot know what changes would have affected them in the 66 million years since their, fictional, non extinction.

So while it is a little difficult to see them being able to pronate their wrists, it is possible to see them shorten their digits and claws and have a hand better able to function as a tool maker. They may not be able to type, but they could make a spear and throw it. But of course they could make a vertical keyboard with keys on either side, and be potentially quicker to use than ours. Think about it and it may make sense, though seeing the keys clearly could be a problem until they got proficient at touch typing. Probably jumping way way too far ahead here, but it's interesting to think about the mechanics of how things are achieved if you cannot pronate your wrists.

Then of course the evolutionary pressure to change the semilunate carpal could itself be their growing intelligence and, eventually when they began to make tools and use their hands in ways they had not before, their wrists begin to change.
 
Feb 2011
6,343
#5
Aren't some humans born with an extra finger? It doesn't sound like much of a leap in terms of mutation to be born with an extra digit, given a large amount of births. Also, would evolving thicker fingers offset somewhat the lack of digits in terms of grasping? Thicker fingers doesn't sound like too big an evolutionary leap.
 

Corvidius

Ad Honorem
Jul 2017
2,550
Crows nest
#7
Aren't some humans born with an extra finger? It doesn't sound like much of a leap in terms of mutation to be born with an extra digit, given a large amount of births. Also, would evolving thicker fingers offset somewhat the lack of digits in terms of grasping? Thicker fingers doesn't sound like too big an evolutionary leap.
There is a rule that says that once evolution has removed something, then it does not come back. However, that depends on how deep this removal was. Birds don't have a long bony tail, but they have not lost their tails, they just have a much shortened modified version. Chickens, in the embryonic stage, form a longish tail, but it is then reabsorbed and the pygostyle appears. They also grow claws on the ends of their hands, which are also reabsorbed and they are hatched with the normal bird fused hand without claws. Likewise they also have vestigial teeth in the embryonic stage. It is thought possible that the genes that switch on tail, teeth and claw growth and the genes that then switch it off, could be manipulated and the "off switch" be disabled, so letting the embryo fully develop into an ancestral state. But as regards the two lost digits, they do not even appear in vestigial embryonic form, so it really does look like they have completely gone from the modern bird genome.

Can evolutionary pressure bring back those digits, or at least one of them, I don't know. The rule that something lost cannot return, is based on finding fossils of an animal with X,Y and Z features, then finding a much later fossil and seeing that it lost Y, and then from further fossils that Y never returned. However, I don't think we can say never as we need far more fossils than we have. We are generally basing certain assumptions on a tiny fraction of the totality of life that has existed before us. So I would say it cannot be ruled out that if an animal started to do something that required an extra feature, even if one long lost, then evolution will find a way.

For these non avian maniraptors in a fictional non extinction world to modify their claws to be shorter, and their three digits to be better able to grasp is completely possible. Their "thumbs" were in fact opposable and could sort of hinge partly over the palm. Not to be able to reach the base of the pinky with the tip of the thumb like us, but the entire digit hinge inwards as one unit. It is not beyond the bounds of evolution to modify this so they were fully opposable, but they would never have the same grip as us, or any other ape, raccoon, meerkat and others.

Dinosaurs as a whole also seemed to be very flexible as far as evolution goes, theropods particularly so, but also others, like Iguanadons with what Thomas Holtz calls a "Swiss army hand", with the three center digits supporting it's weight when they wanted to walk as a quadruped, the pinky was a long grasping digit and the spiked thumb possibly a weapon. Dinosaurs did a lot of clever stuff with evolution.
 
Feb 2011
6,343
#8
For a finger to be there it has to evolve it into being in the first place, so I don't see why evolution can't do it again give the right circumstances. The rule makes very little sense to me. Unless it means that instead of a simple mutation of inert DNA that is switched on again, a gene that is completely absent means evolution will have to start from scratch?
 
Last edited:

Corvidius

Ad Honorem
Jul 2017
2,550
Crows nest
#9
We don't don't have full information on this. While dinosaur eggs complete with embryos have been found, they are, to the best of my knowledge, all of ornithischians, which mostly kept either five digits or no less than four. We need theropod embryos at a very early stage of development to see what vestigial features they had. Modern chickens are just too modern for us to tell what vestigial features still existed 66 million years ago. I don't see a reason why evolution cannot start from scratch, but I do see some problems. Us and Dinosaurs are tetrapods and share a common ancestral bauplan, a head at the front for sensory organs and a mouth, four limbs, a discharge vent and a tail. No matter what bizarre shape tetrapods have evolved into, they have all been the result of loss of or modification of the basic plan. The sail on Dimetrodon is just a modification of the vertabrae, wings of any flying vertebrate just modified arms and fingers, the streamlined shape of cetaceans comes from the loss or extreme modification of the original four limbs. So there isn't really anything new, even if it looks new, it's just a modification of something pre existing. I could be proved wrong, but to the best of my knowledge this is the case.

So, if something that was lost, even from the genome, then evolution would have to create from scratch, and I think, for reasons way to technical for me to explain, would create a move away from the basic tetrapod plan, it could be like going back to our fish stage and creating a new body part. I think it may be impossible, but I have an open mind. While I said that is does look like the missing two therapod digits have gone from the genome, it's not possible to be certain, and I think that the probability is that the five fingered digit plan is still in there somewhere.

But even apart from all that, if you look at terror birds and modern ratites like ostriches, that even while they do have the remains of their long bony tails in the form of ten caudal vertebrae and the pygostyle, in all those millions of years since they became flightless, their long bony tails never reappeared, even when they should have been an advantage in running. So as they did, and do run very well without a tail to speak of, evolution did not, or could not make a tail grow again even with not just the genome, but part of the actual tail remaining. Evolving seems a one way process, and it seems that is was not possible for a highly derived maniraptor like a terror bird or ostrich, to return to a previous stage of evolution.