Regardless of whether it was gradual or happened in a geologic instant, non-avian dinosaurs went extinct by approximately 65 million years ago, but the question of what they might be like today had they survived makes for some entertaining fiction. Most of such imaginary works are set on isolated islands or plateaus, "Lost Worlds" that have provided a refuge for dinosaurs (the most spectacular and enjoyable example being Weta Workshop's companion book to Peter Jackson's remake of King Kong entitled The World of Kong). Still, many of the dinosaurian hideaways do not take evolution into account, theropods, sauropods, hadrosaurs, and horned dinosaurs looking little different from what their Mesozoic forebears were supposed to have looked like during their heyday (Weta's work is a pleasant exception to this rule). There are some authors, artists, and even scientists who have pondered what evolution would have done to dinosaurs had their extinction been avoided, however, the most (in)famous example being Dale Russell's "Dinosauroid."
Unfortunately, I do not have the original 1982 Russell & Séguin paper that first proposed the "Dinosauroid" (pictured above) as a thought experiment, although today the figure is more prominent in online UFO conspiracy forums than in scientific discourse. Our awfully alien-like friend (a point I'll return to later) still crops up every now and then though, and it was a more recent television appearance that inspired me to go back and look at the bug-eyed creature that I was first introduced to during the late 1980's/early 1990's;
This clip brings up an important question, one that has important meaning for our understanding of evolution in general for our own history; are intelligent humanoids destined to evolve? Such a hypothesis invokes a philosophical idea of teleology, and while such a view that evolution direction (or at least inevitable outcomes) is entertained by some scientists, this type of argument is most commonly espoused by advocates of intelligent design. Indeed, those familiar with the views Simon Conway Morris will likely recall his long-standing public feud with Stephen Jay Gould over the Cambrian fossils of the Burgess Shale and the role of contingency in evolution relating to this issue, a topic that will loom large in this somewhat cursory analysis of the Dinosauroid and it's philosophical underpinnings.
Before going into why Russell's evolved Troodon looks so eerily familiar on multiple levels, I should reiterate what Russell has said in the past; the Dinosauroid was primarily a thought experiment in speculative biology. As he said himself in an interview given sometime in the year 2000;
The "dinosauroid" was a thought experiment, based on an observable, general trend toward larger relative brain size in terrestrial vertebrates through geologic time, and the energetic efficiency of an upright posture in slow-moving, bipedal animals. It seems to me that such speculation remains acceptable, particularly if directed toward non-anthropoid anatomical configurations. However, I very nearly decided not to publish the exercise because of the damaging effects it might have had on the credibility of my work in general. Most people remained polite, although there were hostile reactions from those with "ultra-quantitative" and "ultra-intuitive" world views.
Even though Russell stated that the Dinosauroid model is still acceptable, Russell obviously had some reservations about publishing the paper or giving too much attention to his interpretation of a Troodon 65 million years after the end of the Cretaceous. As Michael Ryan noted on his own entry on this topic on Paleoblog, a painting of a family of dinosauroids was planned for Russell's book An Odyssey in Time: The Dinosaurs of North America, and although the maquettes of the scene still exist in museum storage, the illustration was pulled from the book, a decision that I think was wise (despite how interesting such a scene would be). Still, the famous image of a humanoid dinosaur standing next to it's Troodon ancestor is a provocative one, a hypothetical relationship that confronts us with some important questions about our own evolution.
At the time that Russel and Séguin formulated their hypothesis, Troodon was known as Stenonychosaurus inequalis, primarily known from fragmentary material discovered by C.H. Sternberg in Alberta, Canada (the material that bore the name Troodon at that time were teeth initially assigned to a kind of lizard by Leidy and later identified to be from a theropod dinosaur, although not all scientists agreed on this until more material was discovered). Later, in 1969, Dale Russell found a more complete specimen that allowed Phil Currie to identify Stenonychosaurus as synonymous with Troodon in the late 1980's, five years after the emergence of the Dinosauroid in the public sphere. As you can guess, however, it was Russell's more complete Troodon that provided the basis for his speculation, primarily because it appeared to have a very large brain for its size, stereoscopic vision, and the first digit could have some sort of supporting role in grasping. Our problem, however, is determining just how significant each of these features are and if they really could have opened evolutionary paths up to Troodon unavailable to other dinosaurs.
The primary problem that I have with the Dinosauroid and other similar reconstructions is that it rests on the assumption that a level of intelligence on par with extant Homo sapiens would have evolved in one lineage or another if hominids never evolved. How can we be sure this is so? Let's assume, just for a moment, that Troodon really did have the potential to evolve a level of intelligence within the range of Homo sapiens and survived the extinction event at the end of the Cretaceous; would they have survived for the next 65 million years, or at least long enough to evolve a greater level of intelligence? There are entire groups of mammals that evolved after the extinction of the dinosaurs (mesonychids, to name one) that became extinct, so our hypothetical Troodon would not have been free-and-clear during the Cenozoic. Indeed, allowing non-avian dinosaurs to survive the end of the Cretaceous would impact life on earth in ways that we cannot account for, and there would be no guarantee that the group would not go extinct sooner or later due to some other cause.
Given this aspect of contingency, it is difficult to be sure that anything in certain in evolution, especially when the origin of our own intelligence remains mysterious. Even if we were absolutely sure of what led to the evolution of our well-developed brains, our upright posture, and other characteristics of our species, other groups of animals would not be obliged to follow precisely the same path and there would always be uncertainty in our comparisons to the hypothetical intellectual creatures. Convergences do occur in evolution, surely, but most of the well-understood examples (i.e. body shapes of dolphins, sharks, and ichthyosaurs as adaptations to an wholly aquatic lifestyle) do not provide good templates for the evolution of intelligence. Indeed, there's nothing in nature that suggests that Homo sapiens (or its equivalent) was somehow meant to be or would have evolved eventually; there is no goal or endpoint to the evolutionary process, and what is adaptive today might not be tomorrow. Stephen Jay Gould puts this more eloquently in an excerpt from his book Wonderful Life;
Life is a copiously branching bush, continually pruned by the grim reaper of extinction, not a ladder of predictable progress. Most people may know this as a phrase to be uttered, but not as a concept brought into the deep interior of understanding. Hence we continually make errors inspired by unconscious allegiance to the ladder of progress, even when we explicitly deny such a superannuated view of life.
As can be imagined, not everyone agrees with this view, and Simon Conway Morris has done much to speak out against the role of contingency in evolution. In a famous exchange in Natural History magazine about contingency in evolution and its relationship to the Burgess Shale, Morris wrote;
Contingency or no, I believe that a creature with intelligence and self-awareness on a level with our own would surely have evolved--although perhaps not from a tailless, upright ape. Almost any planet with life, in my view, will produce living creatures we would recognize as parallel in form and function to our own biota. But first, life must arise, and we have no idea how rare an event that might be. If we are honest, despite our exciting fancies about extraterrestrials, we must admit the real possibility that life arose but once, and that we are alone and unique in the cosmos--with an awesome and, to many, unanticipated role as stewards of all other living things. But were we to let evolution take another route than it did, why not grant (as, Gould will not) that another kind of being would have evolved to fill our special place in nature?
Morris' view is even more shocking when it is realized that he isn't just talking about intelligence, but the entire evolutionary history of life on earth. If we were to visit another planet that was host to living creatures for as long as ours, we would (in Morris' view) be able to see extant organisms similar to those on our planet and dig up alien equivalents of dinosaurs, temnospondyls, and trilobites, life following the same evolutionary pathways as on Earth. This seems to assume that the planet on which life arose would be similar to our own, but I find it extremely presumptuous to say that life must have evolved in a manner parallel to Earth's when extinction (especially mass or catastrophic extinction) has played an important role in determining what forms of life will be present on a planet during one time or another. Earth is a dynamic planet, changes occurring from the level of tidal pools to continental drift, and the only way to ensure an exact parallel of evolution on another planet would be to "replay the tape" in exactly the same way to an excruciating level of detail. Gould replied to Morris' claims this way;
I am puzzled that Conway Morris apparently, doesn't grasp the equally strong (and inevitable) personal preferences embedded in his own view of life--especially when he ends his commentary with the highly idiosyncratic argument that life might be unique to Earth in the cosmos, but that intelligence at a human level will predictably follow if life has arisen anywhere else. Most people, including me, would make the opposite argument based on usual interpretations of probability: The origin life seems reasonably predictable on planets of earthlike composition, while any particular pathway, including consciousness at our level, seems highly contingent and chancy.
I don't know how else to interpret the cardinal fact that life did originate on earth almost as soon as environmental conditions permitted such an event--an indication, although surely not a proof, of reasonable expectation and predictability; whereas consciousness has evolved only once, and in a marginal lineage among so many million that have graced our planet's history--an indication, although again not a proof, that such a phenomenon is not inevitably meant to be.
Could high levels of intelligence evolved in another lineage on earth if things were different (or on another planet, for that matter)? Absolutely, but such an outcome is not automatically deigned to be. Our own evolutionary history makes it plain that the mere possession of high levels of intelligence does not grant an organism a privileged position, free from threat of extinction, our past history making it clear that evolution produces a branching bush and not a straight line of ever more "fit" forms.
Extinction reveals the effect of contingency in evolution; why did so many of our evolutionary relatives, so close to us in form and mental ability, not survive? If we were to go back to the time when the chimpanzee lineage and the line leading to Homo split and started over again, would we have reached the same outcome? Would another relative of ours, perhaps Neanderthals, survived and developed in a similar way? This is a game of "What if?" that I have no answer to, but it seems clear that high levels of intelligence are allowed to evolve and are not an unavoidable consequence of the evolutionary process.
Returning to the subject of our friend the Dinosauroid, such reconstructions seem to reflect the sort of progression seen in the above illustration of horse evolution. It's easy to pick what may seem like a suitable ancestor and bookend an arrow with a living descendant, but there is a lot of evolution in that arrow that is omitted. This illustration, for one, suggests that once Eohippus evolved it was on the fast track to becoming Equus, the transitions in-between like the growth in size and reduction of toes being intuitive, and it seems that the Dinosauroid is based upon the same sort of logic that largely disregards the way evolution works. In a way, such reconstructions even represent a kind of special pleading, not only implying the survival of a particular species but also clearing the evolutionary path for it to evolve in one way rather than another, in this case taking the form of a human. Even if we are to play along with this idea, would highly intelligent creatures converge on a humanoid body form (as Morris suggests)? Again, not necessarily, and there's no reason to think that high levels of intelligence must be accompanied by an upright, bipedal stance, opposable thumbs, or an overly large braincase. As Darren Naish once wrote on this same topic;
The reason that we humans have the body shape that we do is not - I think - because it's the 'best' body shape for a smart, big-brained biped to have, it is instead the result of our specific lineage's evolutionary history. Given that, so far as we know, the humanoid body shape has evolved just once, we simply have no way of knowing whether it's a particularly 'good' morphology or not. Furthermore, the humanoid body shape is not a prerequisite for the evolution of big brains given that brains proportionally as big as, or bigger than, those of hominids are found in some birds and fish (that's right: humans do NOT have the proportionally biggest brains).
The morphology of Homo sapiens has some advantages (energy efficiency when walking long distances) and some drawbacks (convoluted, narrow birth canals and back pain/injuries), but I don't think that we can objectively call it "good" or "bad," either. Thinking that intelligent organisms must adhere to our shape does little except highlight the hubris that often goes into such considerations. I had mentioned before that the Dinosauroid has appeared more often in tabloid newspapers and alien internet forums than scientific papers, and this is primarily because it looks like the stereotypical alien, itself a sign of bias on the part of our own species. As Carl Sagan wrote in The Demon Haunted World;
The typical modern extraterrestrial reported in America in the '80s and early 90's is small, with disproportionately large head and eyes, undeveloped facial features, no visible eyebrows or genitals, and smooth gray skin. It looks to me eerily like a fetus in roughly the twelfth week of pregnancy, or a starving child. Why so many of us might be obsessing on fetuses and malnourished children, and imagining them attacking or sexually manipulating us, is an interesting question.
...
...the UFO abduction syndrome portrays, it seems to me, a banal Universe. The form of the supposed aliens is marked by a failure of the imagination and a preoccupation with human concerns. Not a single being presented in all these accounts is as astonishing as a cockatoo would be if you had never before beheld a bird. Any protozoology or bacteriology or mycology textbook is filled with wonders that far outshine the most exotic descriptions of the alien abductionists. The believers take the common elements in their stories as tokens of verisimilitude, rather than as evidence that they have contrived their stories out of shared culture and biology.
Oddly enough, it is often birds, the descendants of dinosaurs, that often show us that animals with high levels of intelligence do not have to be upright apes, or even primates. Alex the African Grey Parrot (who recently passed away) possessed extraordinary cognitive abilities, and it has long been known that members of the Family Corvidae (i.e. crows) are extremely intelligent, having brain sizes comparable to that of chimpanzees, dolphins, and humans. Even in turning to non-human primates, Capuchin monkeys have brain-to-body size ratios on par with those of chimpanzees, the New World Monkeys proving to be very intelligent even though they might not be immediately recognized as such as they are arboreal quadrupeds and not apes. Truly, the more animal cognition and intelligence is studied it seems that some have minds that are far closer to our own than we acknowledged previously.
Finally, this brings us to the birds. Troodon was closely related to birds and likely had feathers, but by the time it existed in the Late Cretaceous there were already avians in the air. Even if Troodon survived, would birds have developed higher levels of intelligence first? What if both dinosaur and avian did? It is clear from living species that many birds have high levels of intelligence, however, and so we can say that dinosaurs did evolve high levels of intelligence but look nothing like Homo sapiens, refuting the Dinosauroid model. This becomes immediately apparent when we stop considering ourselves as privileged or superior to other forms of life on this planet, leaving us no reason to think that there is some universal constraint that only also primate-like organisms to achieve intellectual prowess.
At this point I should probably mention the fantastic artwork of Nemo Ramjet, an artist who's Dinosauroids are probably more accurate when considering if dinosaurs were able to evolve higher levels of intelligence. As I've attempted to make clear in this post, however, there's no reason to believe that given a reprieve from extinction at the end of the Cretaceous non-avian dinosaurs would have evolved in such a manner at all (Dougal Dixon's The New Dinosaurs springs to mind here, although it's guilty of supposing fine-tuned convergence in many cases, as well), such a change in history having no set outcome and still being subject to contingency. The extinction of so many of our own evolutionary relatives like Paranthropus show that intelligence does not provide an evolutionary free ride or have inevitable consequences, making the development of intelligence all that more special and rare. As fulfilling or enjoyable as it may be to construct evolutionary narratives to elucidate how evolution made us what we are, we should not attribute the role of "Mother Nature" to evolution; nature neither cares for us or despises us, and it is that fact that makes our present condition all the more spectacular and valuable.
References;
Gould, S. J. Wonderful Life W.W. Norton, 1990.
Hecht, J. "Smartasaurus." Cosmos. Issue 15, June 2007.
Hopson, J.A. "Relative Brain Size and Behavior in Archosaurian Reptiles." Annual Review of Ecology and Systematics, Vol. 8. (1977), pp. 429-448.
Larsson, H.C.E., et al. "Forebrain Enlargement Among Nonavian Theropod Dinosaurs." Journal of Vertebrate Paleontology, Volume 20, Issue 3 (September 2000), pp. 615-618
Morris, S.C. & Gould, S.J. "Showdown on the Burgess Shale," Natural History magazine, 107 (10): 48-55.
Naish, D. "Dinosauroids Revisited." Tetrapod Zoology [Blog], November 02, 2006.
Russell, D.A. "Speculations on the Evolution of Intelligence in Multicellular Organisms." CP-2156 Life In The Universe Conference.
Russell, D. A., & Séguin, R. 1982. "Reconstruction of the small Cretaceous theropod Stenonychosaurus inequalis and a hypothetical dinosauroid." Syllogeus 37, 1-43.
Sagan, Carl. The Demon Haunted World.Ballantine Books, 1996.
Stevens, K.A. "Binocular Vision in Theropod Dinosaurs." Journal of Vertebrate Paleontology. Volume 26, Issue 2 (June 2006), pp. 321-330
Stock, C. "The Dawn Horse or Eohippus" 1947.
- Log in to post comments
I find it amusing to consider things from the other direction. Not "what if dinosaurs had not died out but had evolved into sapient beings", but "if some species of dinosaur HAD evolved sapience, how advanced could their society have gotten and still left absolutely no recognizeable trace 65 million years later?"...
Not so much about the dinosaurs but just question of whether or not there is anything a civilization could do that would leave recognizeable traces after 65 million years...
There's quite a bit of science fiction about just that, SMC, one story in particular coming to mind about a ground of "sapient" dinosaurs that survived the meteor impact and were scattered around. Lots of television shows, from both incarnations of Land of the Lost and the TV series The Lost World had such dinosaurs, although they always seemed to be lurking around in caves/not have much architecture to be preserved. My favorites, though, are the dinosauroids of Xenozoic tales that communicate through Scrabble tiles.
Your last comment reminds me of another quote as well, which I will promptly dig up and post and such a question has been considered before.
The insistance on humaniform sentients is nothing short of pathetic. Darren is far too kind: that the human shape has only ever evolved once is itself evidence that our form is far from the best possible. That is, if it were any good, there would be (or once have been) other animals like us.
Nathan makes a good point. Dolphins and ichthyosaurs mimicked sharks because that form works so well in their environment. If our upright, bipedal posture worked so well, you'd think other organisms would have figured it out first (or second).
At any rate, the Dinosauroid always makes my stomach queasy. The very idea that evolution will eventually churn out a hominoid-like body plan is unrealistic. I have the same problem with several of Dougal Dixon's "new dinosaurs," in which the author takes a modern animal, slaps a dinosaur or pterosaur bent on it, and calls it good. We've got pterosaurs that are really giraffes, a coelurosaur that's a flamingo, etc. It gets harder and harder for me to read that book.
I think you've given me a topic to blog about, Brian...*begins brainstorming*
I really love Ramjet's work, and I would really like to see the animals who painted those pictures.
It is interesting to consider SMC's question with a different angle.
What if in their 165 million years of existence some form of Dinosaur did evolve intellegence?
Now granted I'm not seriously proposing they did, but if one or even two groups did over the run of the mesezoic what are the odds of us finding the evidence?
I JUST wrote a huge reply to the next post on Laelaps (the post on the creationist birthday of the Earth) about how evidence of civilization is pretty short lived in the geologic record. Wood, bricks, cement, metal it all erodes, decomposes, or disintegrates back into the surrounding environment within thousands (not millions) of years. Thus meaning if Dinosaurian civilizations existed we'd be hard pressed to find these remains. (Just look at the ongoing Arcky efforts to find a few thousand year old Troy...)
I mention this as a reference to the ONLY cool part of the Star Trek Voyager episode with hyper evolved Dinosaurs in the "present" (i mean geologic present as star trek is only a few hundred years away ;p)whose ancestors saw the need to expand beyond the earth and went into space before the KT extinction. The ep has a part where one of the star fleet people say "it's possible we just haven't found the evidence of your peoples civilization on earth" to the 65 million year old evolved dinos.(sidenote: sadly like the rest of Voyager this episode was SO stupid otherwise... example of all the dinosaurs they picked to evolve to intelligence they picked hadrosaurs!?!)
I found that line very interesting as I was part of a one day research project that showed pretty darning evidence that civilizations just don't leave a big stamp on the geologic record (outside of atmospheric and radiation traces on the geology, but these won't be clearly caused by intellegent beings... imagine the cause of late cretaceous global warming being fossil fuel using dinos ;p)... we were only looking at evidence surviving 1 million years into the future of human civiliazation and couldn't prove much would survive... I'm not going to retype this though. Check out my comment on the next post on Laelaps.
We'd than have to relay on more passive means of detecting intellegent Dinos. Mainly that of fossil remains. Which as we know has a low probitility anyways due to less than .01% of living things being fossilized (though there'd be a higher chance if their civilizations were like ours in building their population by water sources).
This than comes back to the brillance of Brian's post, and the problem with assuming bipidalness with intel. Maybe (though I personally do NOT believe... so please don't call me a quack! I'm just saying for fun and sci-fi's sake) we already have the remains of ubber intelligent Dinosaurs, and just haven't realized it...
Perhaps even scary the hack writers of Voyager were right and it is a Hadrosaur *Traumador shudders*
However
One more quick thing. Just watched the video...
You know Morris is wrong when Phil (Currie) sides against him! One of the judges of my one day research project was Phil (see my comment on the next post for this story... it's long and I should be doing homework!) Phil's the dude!
Now if only the intelligent Dinosaur colony that fled to the stars would just launch their invasion of earth so I don't have to do my homework LOL...
Hey that could be a new explanation for the greys and UFO's... not aliens but returning evolved dinos hmmmmmmmm
Welcome to Sci Blogs. Another fine article. People are going to think you don't have enough to do with your time if you keep posting at length like this!
SCM's curious telelogical views are, I believe, based in his personal interpretation of Christianity, an attempt to find a place for divine predetermination without actually abandoning natural selection as a mechanism. I can't find a reference, but I'm pretty sure I've read this on a dead tree.
The thing about identifying very old intelligence in the record is that to a large extent it depends on how intelligent you want it. A mesozoic equivalent to the Oldowan culture would surely be completely untraceable, whereas a high tech, steel using civilisation would be more likely to leave surviving traces. At what point on the cultural continuum would you expect to start seeing anything?
Thanks for the comments, everyone! Our own form of bipedalism seems to have been constrained/molded in a particular way because we evolved from arboreal ancestors; the placement of our shoulder blades on our back rather than on our sides allows our arms a much greater range of motion and is indicative of an ancestor who hung below the branches of trees and probably brachiated (arboreal quadrupeds, like Capuchins, have their shoulder blades on their sides). Indeed, our past history can tell us a lot about why we have the form we do, and as I wrote earlier I don't think it can be termed "good" or "bad."
Chris; I didn't want to go into it in detail, but SCM's ideas do seem very much tied up with his faith, and what he mentions about convergence in the video is interesting because he's been awarded funds from the infamous Templeton Foundation to create a sort of database of evolutionary convergence. Such a database could be useful, but I have to wonder (even fret) that SCM's philosophical views will get wrapped up with it and the database will attempt to show direction/purpose/teleology in evolution in order to make it consonant with the idea that man was somehow "meant to be."
You also make a good point about technology, and we've been discussing that a lot in my Topics in African Prehistory class. Mt. Assirik chimpanzees, for example, use baobab trunks/limbs as anvils to crack the nuts of the tree, and other primates use stones and sticks as tools. Because these tools are not heavily modified, how can we tell when they started to be used? My professor is looking into just that (i.e. the patterns of wear on hammers/anvils used in the way chimpanzees and capuchins do today), but the presence of culture and technology is more difficult to discern the further back in the "cultural continuum" you go.
For all species, through all times, then "Life is a copiously branching bush, continually pruned by the grim reaper of extinction, not a ladder of predictable progress" but for any given species at any given point, there is indeed a ladder from the first cell to that species. It's just that showing only such a ladder is misleading in that it doesn't show what could have happened and what didn't happen as that particular species climbed its own ladder amongst all the other ladders being climbed by other species, most of which were considerably shorter than the ladders all extant species are sitting atop.
Stephen Jay Gould probabbly got it right when he criticised teleology, but, in my opinion, some of his examples in *Wonderful Life* were rather badly chosen. The idea that sentience would have never evolved without the K/Pg impact was such an example. Goulds line of arguments was that in this case, non-avian dinosaus would have remained the dominant terrestrial life form, and would never have developed sentience because of the innate restrictions of the (eu)reptilian brain. But for all my best knowledge, such restrictions do not exist. Parrots and corvids are good eureptilians, but they beat most mammals for intelligence. And, of course, the terrestrial niche that is most likely associated with higher degrees of intelligence - arboreal frugivores and omnivores - was not occupied by non-avian dinosaurs, but by metatherian polidolopids and probably birds in Maastrichtian North America (the only terrestrial ecosystem of the immediate pre-impact era with a reasonable complete fossil record), so the influence of non-avian dinosaurs on the development of higher levels of intelligence would have been rather limited even in a hypothetical non-impact scenario.
Judging by repeated experience (e.g. Pacific Islands, North and South America, the present), the best and most reliable indicator of the advent of a sentient species is ecosystem-wide mass extinction, both terrestrial and aquatic, particularly affecting larger species, and starting with large predators.
By that measure, the upper-Cretaceous extinction is practically unimpeachable evidence for the rise of a sentient dinosaur. That would also explain why so many species declined sharply below the iridium layer. And -- who knows? -- maybe the asteroid didn't just fall. Maybe it was pushed.
Surprising myself, I'm not entirely kidding.
I should write about speculative zoology more often if it'll stir up this much attention and detail...
Ian; you're right in that we can trace ancestry to the exclusion of others, following the "ladder" within the branches. I think the two ways of looking at evolution have caused much of the debate over how evolution proceeds, although I think there are good and bad points with both models.
Johannes; Like I said in the post, very intelligent dinosaurs did evolve in the form of birds, so you're right there. I think what Gould was saying, though, was that intelligence was not "destined" to be evolved; it could evolve in a different lineage, sure, but life is not spurred on to this point. That's the main contrast between Gould and SCM, I think; SCM thinks life must proceed in a particular fashion towards a certain end while Gould says that evolution does not have a direction and things could be very different today if we "replayed the time." Morris makes this mistake in the excerpt I quoted in the post asI don't think Gould is saying that intelligence in another group of organisms could not have evolved but rather that there is no requirement for it to evolve (i.e. it does not represent a "next step" that evolving organisms must go through).
Nathan; I can understand how mass extinctions pave the way for new radiations of life forms (the end-Cretaceous event being a good example given the radiation of mammals), but I don't follow how such extinctions are necessarily good for the development of intelligence. Even after the K/T boundary there were mass extinctions and our own intelligence did not develop fully until very very recently, so I don't exactly follow how a mass extinction would be a direct cause. Sure, they "shake things up a bit" and allow the diversification of surviving life forms, but those life forms are still subject to various constraints and contingencies (65 million years is a long time).
Brian, you miss my meaning entirely. Just as the present mass extinction, still in progress, may be traced directly to our (i.e. sentient apes') collective doorstep, I'm blaming the K-T mass extinction on the ill-considered collective activity of our hypothetical sentient dinosaur.
To reroute an asteroid onto a collision course would be spectacularly ill-considered, but the difference from past and present behavior of members of our own species is only one of degree.
SMC, my comment above touches on your question: which legacy of humanity (past or future) could possibly compare to our planetwide holocaust of animal and plant species, terrestrial, aquatic, and avian alike? And, how could any future civilization fail to notice such evidence? Of course, it's one thing to notice it and another to interpret it correctly.
When I saw photos of the Dinosauroid-model many years ago, I made sense for me. But now, many years later as I have learned much more about biology, evolution and paleontology I am also sceptical about it. I think one of the main reasons why we look how we look, is that already our ancestors were not quite different. Even most small monkeys have a more or less round head, a short face and are able to stand at least for a short time upright. But why should for example a dinosaur which can balance with its tail evolve a walking style like ours?
Something I find really fascinating is the idea, what creatures could have evolved, if other lines of primates had evolved to human-like being. Some monkeys already have a very human look, especially if you look at their eyes. But they do have also a huge variation of skin, hair and eye colour, not to speak about all the different hair-and beard-styles or the ability to use a tail. I could well imagine that many primates would have the theoretical potential to evolve in humanoid creatures. But they could at the end look VERY different to us. Just imagine the white Uakari would evolve to a humanoid (okay, this is lesser probably, because it is very specialized, but such a humanoid would look really strange - and ugly)or a humanoid with a Rhinopithecus roxellana as ancestor.
Interesting ideas, Sordes. There are a lot of similarities between us and our primate relatives, but it seems that our ancestors arboreal habits had a lot to do with our present state. The change from arboreal quadrupedal running (shoulder blades on the sides of the body) to brachiation (shoulder blades on the back and the ability to for overarm throwing/striking/etc.) seems to have played a large part in our becoming upright obligate bipeds, although this wasn't the only factor.
Still, we'll never know what could have evolved if things were different, although I would love to see what primates millions of years from now would look like (if they were still around).
Sordes,
they had a hypothetical ground-living uakari in "The Future Is Wild".
The idea was that in 5 million years, the climate will be so cold and dry that grassland replaces the Amazon rainforest, thus forcing the uakaris to become steppe dwellers. The resulting animal was, however, a baboonoid rather than a humanoid and was actually called the Babookari.
The Babookaris in the TV Show were able to make fishing nets, but otherwise they showed no traces of sentience.
Yes, I remember those fishing uakari-descendents, but like many other creatures of "The Future is Wild" they seems somewhat unprobable. Okay, this is perhaps also because the animation and design of those creatures was in some cases really bad, but many of them were actually biologically impossible.
I had also thought about the possibility of stereotypical not-human fantasy humanoids could have theoretically evolved. In fact early lines of hominids could have well resulted in orc-like creatures, or other lines in small robust hominids which would look like dwarves. If we look at the actual fossil record, there was in fact a comparably wide radiation even among hominid. Even our own species shows a huge variation.
Something I really dislike about intelligent races both in science-fiction and evolution-biology is the idea that they would be very human-like. But this is really not necessary. If the first vertebrates which coloniced the land had had six limbs instead of four, evolution had gone completely different ways, and had perhaps culminated in cantaur-like intelligent beings. Even an animal without any fingers or hands could have the potential for becoming really intelligent. If you keep in mind how highly skilled elephants are with their trunks, and that they even tools with them, an intelligent being with four legs but anatomical adaptions on the head which would enable tool-use could also be possible. I once sculpted for fun a C´thulhu-like humanoid-like squid-creature, which uses its tentacles like arms and fingers. It can be seen here:
http://www.tonmo.com/gallery/showphoto.php/photo/686
This is only a fantasy and very unlikely creature which is based on a sketch I did draw many years ago. But it shows more or less what I mean.
> Yes, I remember those fishing uakari-descendents, but like many
> other creatures of "The Future is Wild" they seems somewhat > unprobable.
Those things were able to make a complex structure like a fishing net, but were unable to make spears, wich are simply pointed sticks, the most simple of structures. Their main - or perhaps only - enemies were predatory flightless birds. The simplest of spears would work wonders against a maniraptoran or indeed any other coelurosaur, just pierce the thorax and the lungs and air-sac system collapses. So there would have been lots of pressure toward the development of spears, and little pressure toward the development of fishing nets - the environment was described as beeing pretty dry, without many rivers or lakes suitable for fishing. Inprobable indeed.
> If the first vertebrates which coloniced the land had
> had six limbs instead of four, evolution had gone completely
> different ways,
Dragons :-)
> I once sculpted for fun a C`thulhu-like humanoid-like
> squid-creature, which uses its tentacles like arms and fingers
Nice sculpture! I think the only thing thats stops cephalopods from becoming sentient is the fact that most - if not all - of them die immediatly after reproduction, thus making it very difficult for them to develop complex social structures like herds, packs or pods.
I'm going to have to agree. Nemo Ramjay's images Are absolutely beautiful. Also, am I the only one who gets really creeped out by the troodon-sapiens image on the top of the post?
Welcome to Scienceblogs, Brian.
Great post!!!
I know that this post was about Dinosoroids and whether homoinoids were, as SCM suggests, likley to evolve in other lineages but you quite rightly pointed out there is a deeper issue at stake here - the predictablity of evolution.
If we leave the contentious issue of hominoids aside and conway-morris' apeal to a "theology of evolution" (what ever that is!). His argument for the power of convergence becomes much more interesting. It provides very strong support for the theory of evolution by means of natural selction.
That the same design solutions are found time and again to many of the problems faced by organisms set by thier physical environment,shows us how well adapted organisms can be to the world around them and does not fit with the highly contingent view of evolution potrayed by Stephen Gould.
The question of where contingency applies to evoluition is one of scale, the details are contingent but the patterns need not be, much of an organisms shape and behaviour is highly predictable, e.g. the shape of leaves are often used by paleoecologists to reconstruct the rainfall patterens of past environments as leaf shape adapts to prevent damage. The gap in ecospace reprented by 'reefs' has been filled on 5 seperate occasions following mass extinctions, and given a few detils on an animals ecology zoologists are able to make highly accuarte predictions as to its likley mating system.
It appears to me as though Conway-Morris opens our eyes to the possibility of a new theory of animal form, long sought in the tradition of D'acy Wentworth Thompson, where an undestanding of the physics of an organisms environment and the mathmatial princiles governing it growth our central to our understanding of the world around us.
(Regarding hominoid forms: at present I side with John Maynard-Smith in his review of Wonderful life in the NYT, who said we just don't know! Both Gould And Conway-Morris' positions are led by thier personal beliefs.)
I am just a regular guy, young black guy. Why this interests me....? Bali Indonesia 07, I had an "experience" with what I thought was an "alien". Long head, BROWN, walked like a pigdeon(its joints at the knees bend forward not backwards like ours). ((Long story)) I am convinced that it was a Troodon evolved. Who would have guessed, dinosaurs on spaceships.
Some of them went into space some stayed here. The ones reamaining on earth survived the K-T extinction, hence the world wide spred of the "dragon myth". Those in space have kept watch on humanity and prevented any other races from interfering with our development.
SMC, my comment above touches on your question: which legacy of humanity (past or future) could possibly compare to our planetwide holocaust of animal and plant species, terrestrial, aquatic, and avian alike? And, how could any future civilization fail to notice such evidence? Of course, it's one thing to notice it and another to interpret it correctly.
terrestrial, aquatic, and avian alike? And, how could any future civilization fail to notice such eviden
xperience" with what I thought was an "alien". Long head, BROWN, walked like a pigdeon(its joints at the knees bend forward not backwards like ours). ((Long story)) I am convinc
SMC, my comment above touches on your question: which legacy of humanity (past or future) could possibly compare to our planetwide holocaust of animal and plant species, terrestrial, aquatic, and avian alike? And, how could any future civilization fail to notice such evidence? Of course, it's one thing to notice it and another to interpret it correctly.
All hail to our Reptilian Overlords !
Evolution, intelligence and environment - the rotting suspension bridge
I am no biologist, but rather a historian. With reference to the NASA equation on the chanches of discovering intelligent extra terrestrial life and the current debate on global environment, I would like to propose a hypothesis I like to cal the rotten suspension bridge. I guess am not the first to have done so, however.
If one asume that intelligence will allow for the exploitation of an increasingly wider range of resources, the sustainability of a speices would be the rotting suspension bridge and the speed at which one moves across be the inovative force of the species. That is, an intelligent species only survives as long as its level of inovation is keeping pace with its ability to procreate and exploite available resources. If not, the suspension bridge collapses and the creatures fall to the abyss. This I guess would be especially a risk when a society devolops a religious beleife or politicall ideology that leads to stagntion.
SMC, my comment above touches on your question: which legacy of humanity (past or future) could possibly compare to our planetwide holocaust of animal and plant species, terrestrial, aquatic, and avian alike? And, how could any future civilization fail to notice such evidence? Of course, it's one thing to notice it and another to interpret it correctly