Sorry, but it is a basic principle in biology that a Master Race does not scuttle into hiding when you turn on the overhead light in the kitchen.
“We’re marching to a faster pace…
Omigod! Run!! RUN!!!”
It is… and it isn’t. The main thing to appreciate is that the three aren’t independent. One enabled the other which enabled yet another.
What you are saying is a bit like pondering that a state lottery winner had to be in that state on that date, had to buy a ticket, then own a winning ticket, then return the winning ticket to collect the prize. Any of those things on its own is staggeringly remote by chance alone, after all most people don’t buy tickets, many people on this planet are innumerate, many people never check the lottery results and so forth. So on the face of things it seems like winning the lottery would be impossible because there are so many factors involved. But in reality the only independent probability is the probability of buying the winning ticket. Everything else is interconnected: people who play the lottery will usually check their results, people will usually play the lottery in their home state as opposed to ordering tickets from Alaska or Hawaii by mail and so forth.
The same applies to the traits needed for human intelligence and society. Apes are intelligent because we have grasping hands and live in societies. We evolved language because we were intelligent and live communally. The three traits you describe are all interconnected.
Australopithecines had an upright posture and grasping hands, but no language and less intelligence than a chimp. Intelligence evolved later because upright posture and grasping hands allowed it o be useful. Language evolved still later precisely because it had a use for creatures with upright posture, grasping hands and intelligence. So really it was only the evolution of upright posture in primates that was required. Everything else was connected to that one event.
Luck didn’t have anything to do with it. Dinos never had opposable thumbs, so even though they evolved upright posture at least twice intelligence was never beneficial to them. And lacking intelligence they never had any use for language.
You can’t randomly produce traits like intelligence or language in fully developed form. It is a gradual process and if your anatomy doesn’t allow the very earliest forms to be beneficial then the process stops there.
Jellyfish we can give up on. Radial symmetry and centralised nervous control are mutually exclusive, never mind that jellyfish don’t have any neural centralisation at all.
Arthropods are behind the eightball because they have there nerve cord located on the underside of their bodies. That places all sorts of constraints on size and intelligence. Without some fundamental restructuring to the point where they are no longer recognisable as arthropods cockroaches can’t evolve intelligence.
No. When the very first cockroach came into existence your ancestor was alive right beside it. In fact your ancestor may well have eaten the very first cockroach that ever existed. Your lineage is every bit as ancient as any cockroach’s.
The fact that cockroaches have been stuck in an evolutionary cul-de-sac for 400 million years doesn’t make them any more ancient. It just means that they were stuck while your ancestors moved on. But you and a cockroach have been on the same journey for exactly the same period of time. There lineage hasn’t existed for longer than your lineage.
Less intelligence than a chimp? Can we have a cite for that?
I think it could probably be reasonably argued that the cockroach lineage has experienced more evolution than the human one (even though less morphological change appears to have occurred) - more, because there have been more generations of cockroach ancestors in that time than there have been generations of human ancestors.
Sure, heres one. I didn’t think this was particularly surprising. Even Gould once refereed to the early Australopithecines as slightly dim chimps, or something very similar.
Obviously we can’t measure intelligence of dead species, we can scarcely do that for living species. All we can do is extrapolate from the information we do have. Australopithecines, or at least the earliest forms, had relatively smaller brains compared to their body mass than do chimps.
We can’t really say that. In that time period the human lineage was probably mostly breeding continuously for at least 8 months a year, one litter every 6 weeks, maturity reached at no more than six weeks. Remember for most of that time we were akin to mice or shrews. Cockroaches in contrast may well have been breeding only once or twice a year as most species do now.
Of course we can’t know for sure, but we can’t rule out that in that there have been far more generations of human ancestors.
OK, now I’m really confused. From your cite:
Emphasis added. Did I miss something?
Most anthropologists I’ve read postulate about equal intelligence. But that’s really just an educated guess based on euqivalent brain size. You might find some argument that Paranthropus robustus (the hominid formerly known as Australopithecus robustus) was a bit dim-witted, but that’s also just a guess, and is based also on its reliance on a more specialized diet.
That’s fair enough; there are probably other factors too; for example the frequency at which mutations arise; if this is significantly (and consistently) greater for one lineage than the other, then again, I think it could be argued that this lineage experiences more (of) evolution.
John Mace and Blake, thanks for the replies.
What I was thinking is that opossums have opposable thumbs and they’re dumb as rocks, and elephants have grasping trunks and, although bright, they can’t make tools like chimps or crows. Parrots pick things up with their feet and they’re intelligent–not as much as we are, but enough that I think they’d do better if they had language. Feel free to comment on anything I’m missing.
I know.
Every so often, my little flying Alvin gets this wistful look in his eyes, like he’s thinking about the good old days, when his ancestors were in charge, and we mammals were cowering in the leaf litter. I guess that made me think that at least one of those ancestors got closer to opposable toes (or thumbs) and intelligence than they did. That, and taking Jurassic Park at all seriously.
Why is that? That is, why does it constrain them, not why is the nerve cord where it is; the latter is the kind of thing I’d always ask in high-school biology, and my teacher would say, “Do you want me to answer as your biology teacher, or do you want me to answer as God?”
Just a few random comments about parrots:
-They do have language - I’m not talking about mimicry (although I believe there is at least tentative evidence that mimicry isn’t just ‘parrot-fashion’ mindless repetition) - I’m talking about body language and vocal communication. No capability to discuss abstract concepts though, as far as I know.
-The grasping feet are would seem to be a result of adapting to climb about amongst branches - a similar general need and response as our own grasping hands (or those of primates generally), which is an interesting correlation, I think.
-They’d do better if they were able to grasp and walk at the same time
-They don’t really have the body mass to be able to attack tool technologies.
So one of the pre-flight ancestors of birds - some medium-sized bipedal dino with forearms - could therefore well have been a candidate for adaptation into an intelligent, tool-using world-beater. It just failed to happen, is all.