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wd40
2011-Dec-12, 01:47 AM
If the behaviour of the velociraptors in "Jurassic Park" was an accurate depiction, then dinosaurs were quite intelligent, social and cooperative. It is speculated that had dinosaurs not become extinct 65 milion years ago, thereby giving mammals and ultimately humans a chance to evolve, which otherwise would not have happened, the world today would instead be dominated by bipedal reptile versions of ourselves, descended from dinosaurs, something like the Hirogens of Star Trek Voyager.

Apart from his brain, the key to human predominence is his opposing thumb. If humans became extinct tomorow, could we expect in 65 million years time an equally succesful and intelligent species having evolved to take over the planet, but deriving from a totally different branch of the animal kingdom, eg the supposedly intelligent squid family?

Noclevername
2011-Dec-12, 01:52 AM
There's no particular reason any species would "succeed" us, I.E. become sentient tool-users with civilization. Evolution doesn't work that way.

As for the accuracy of dinosaur behavior in JP, it was probably about as accurate as their appearance.

Solfe
2011-Dec-12, 02:15 AM
I can't help but think of the story "City" by Simak, where dogs and robots debate the existence of (a now absent) mankind.

Gillianren
2011-Dec-12, 02:23 AM
There's no way to predict what will come after humans are no more, because that would assume that evolution follows a predictable path. There's no reason to assume that.

HenrikOlsen
2011-Dec-12, 03:54 AM
Seeing that our ancestors at the time of the dinosaurs were shrew-like herbivores, brain-wise likely dimmer than a sickly glow word, I doubt our guesses at what's going to evolve, and how, is going to be any good.
Intelligence now isn't an indication of who will be intelligent in 65 million years.

Some things are possible to tell, e.g. a general prediction such as: There will be several arms races where a prey and a predator species get caught in a mutual feedback loop where they drive each other down the "better armor to protect against better weapons to penetrate better armor" blind alley, followed by both going extinct.
But that's just because it's a general pattern that's been followed several times already, there's no telling which pairs of species are going to go there until it's well under the way.

Squid would be an unlikely ancestor of a hypothetical land living successor because of their strong dependence on being wet for oxygen absorption and reproduction.

Jens
2011-Dec-12, 05:31 AM
If the behaviour of the velociraptors in "Jurassic Park" was an accurate depiction...

Well, if the behavior of ants in A Bug's Life is an accurate depiction, then I have no doubt they will take over after we become extinct.

Jim
2011-Dec-12, 01:09 PM
Well, if the behavior of ants in A Bug's Life is an accurate depiction, then I have no doubt they will take over after we become extinct.

Why wait?

wd40, you might give West of Eden by Harry Harrison a read. Interesting speculation.

Cougar
2011-Dec-12, 04:33 PM
Apart from his brain, the key to human predominence is his opposing thumb.

We can get some idea of where evolution might go by identifying convergent evolutionary features. (http://en.wikipedia.org/wiki/Convergent_evolution) The opposable thumb is apparently not one of those features.

HenrikOlsen
2011-Dec-12, 05:17 PM
Apart from his brain, the key to human predominence is his opposing thumb.
A body adaptable to a very wide range of climates (nude (i.e. unprotected by clothes) humans have a range going from 32F/0C (Terra del Fuego) to 104F/40C (African and Australian deserts)) is just as much an advantage that few other animals can compete with.
A digestive system that'll handle a vary wide range of foods is an advantage we share with few animals other than rats and pigs.

We can live anywhere and eat everything.

Don't diss those advantages just for the luxury of the thumb, there are lots of alternative to thumbs that are just as good.

wd40
2011-Dec-12, 06:16 PM
If humans did become extinct and one came back 65 million years from now to find that not only had no dominant or intelligent species evolved, but that all flora and fauna were exactly the same as today, would we say that 1) the theory of evolution is incorrect, 2) our interpretation of it is incorrect, or 3) evolution has ceased, and right now is as good as it gets?

Is no smidgen of speciation, macro-evolution or new organs at all over the next 65 million years from now a conceivable scenario?

Ilya
2011-Dec-12, 06:37 PM
If humans did become extinct and one came back 65 million years from now to find that not only had no dominant or intelligent species evolved, but that all flora and fauna were exactly the same as today, would we say that ...

I would say I am living in a bad simulation.

The question is as meaningless as "If water flowed uphill, what would you say?"


Is no smidgen of speciation, macro-evolution or new organs at all over the next 65 million years from now a conceivable scenario?
It is not.

Noclevername
2011-Dec-12, 06:45 PM
If humans did become extinct and one came back 65 million years from now to find that not only had no dominant or intelligent species evolved, but that all flora and fauna were exactly the same as today, would we say that 1) the theory of evolution is incorrect, 2) our interpretation of it is incorrect, or 3) evolution has ceased, and right now is as good as it gets?

Is no smidgen of speciation, macro-evolution or new organs at all over the next 65 million years from now a conceivable scenario?

Evolution is a part of life. As long as life continues, the process of evolution will continue. Mutations happen in every generation. Conditions continue to change, and life continues to adapt to those changes or it dies.

Gillianren
2011-Dec-12, 06:53 PM
What would cause evolution to stop? It hasn't now and is going on all the time, so you'd have to posit a mechanism to cause something we observe (and, yes, that includes speciation) to stop happening. I'm going to second "bad simulation."

Swift
2011-Dec-12, 06:53 PM
Is no smidgen of speciation, macro-evolution or new organs at all over the next 65 million years from now a conceivable scenario?
It is inconceivable.

It is inconceivable 65 years or 65 months from now. Evolution is observed all the time. Read some books on the topic, such as "The Beak of the Finch: A Story of Evolution in Our Time"

Rhaedas
2011-Dec-12, 07:08 PM
Partially because it would be highly improbable that the environment stay exactly the same over 65 million years, and the environment strongly drives selection.

publiusr
2011-Dec-12, 07:11 PM
We can get some idea of where evolution might go by identifying convergent evolutionary features. (http://en.wikipedia.org/wiki/Convergent_evolution) The opposable thumb is apparently not one of those features.

Well, there was Gould's blurb about the Panda's Thumb--so, in a few million years--we'd be replaced by Jack Black's character right as the Sun moves towards its Red Giant phase...

pzkpfw
2011-Dec-12, 07:13 PM
.. but that all flora and fauna were exactly the same as today ...

Where did you get that from?

Swift
2011-Dec-12, 09:02 PM
If humans did become extinct and one came back 65 million years from now to find that not only had no dominant or intelligent species evolved, but that all flora and fauna were exactly the same as today, would we say that 1) the theory of evolution is incorrect, 2) our interpretation of it is incorrect, or 3) evolution has ceased, and right now is as good as it gets?
My bold

This choice needs to be commented upon. It demonstrates a common, but fundamental misunderstanding. Evolution does not proceed towards a goal of increasing complexity or intelligence or other similar characteristic of organisms (and those stating this misunderstanding also usually add something along the lines that humans are the "peak" of whatever characteristic this is).

The only driver of evolution is that the organism has a better "fit" to its environment such that it reproduces more than other organisms. If the specific environment gets hotter, then organisms that can survive heat better will probably reproduce more; if it gets colder, the opposite will happen (this is a very simple example). But being tolerant of heat or cold isn't somehow fundamentally better, except as it applies to that specific environment.

Since the environment is constantly changing (whether because of climate changes, geological changes, or whatever), what is the "best" fit constantly changes too. So unless and until Earth became a completely static environment, evolution can not cease and there is no "good as it gets".

HenrikOlsen
2011-Dec-12, 09:47 PM
Evolution can't stop until every living thing is either dead or immortal, it's a fundamental property of anything that makes imperfect copies of itself.

Note that wd40 is demonstrating one of the really elementary properties of logic, if you assume a contradiction you can prove anything.

BioSci
2011-Dec-12, 10:15 PM
Since the environment is constantly changing (whether because of climate changes, geological changes, or whatever), what is the "best" fit constantly changes too. So unless and until Earth became a completely static environment, evolution can not cease and there is no "good as it gets".

And as HenrikOlsen commented, as long as imperfect replication (and limited survival) is involved, evolution must occur - even in a static environment.

transreality
2011-Dec-13, 12:04 AM
The last 65 myr have basically been the age of the mammal. As we go, we seem to be taking a lot of mammal species with us, especially the big ones. Maybe mammal diversity will not recover... if which case birds may be well placed to reclaim the earth, they seem to be a successful and very diverse group.

Certainly things will be very different in 65myr, the evolutionary process is subject to many contingencies from now until then, so it is impossible to predict the outcome, and not necessarily that intelligent species will emerge. It may be that even the more intelligent species currently are a result of selection in a environment affected by humans, they may not survive our passing.

HenrikOlsen
2011-Dec-13, 01:28 AM
The last 65 myr have basically been the age of the mammal. As we go, we seem to be taking a lot of mammal species with us, especially the big ones. Maybe mammal diversity will not recover... if which case birds may be well placed to reclaim the earth, they seem to be a successful and very diverse group.

Certainly things will be very different in 65myr, the evolutionary process is subject to many contingencies from now until then, so it is impossible to predict the outcome, and not necessarily that intelligent species will emerge. It may be that even the more intelligent species currently are a result of selection in a environment affected by humans, they may not survive our passing.
Like mimicry and vision, intelligence, at least up to a point, does seem to be one of the universals. It's been developed repeatedly to increase survival in many species independently.
As for us driving them to it, we haven't been interacting enough with cephalopods to make them as intelligent as they are. Don't try to take the blame, we're not that special. :)

FarmMarsNow
2011-Dec-13, 03:24 AM
Because of convergent evolution I think it will be another mammal. My money is on the racoons.

HenrikOlsen
2011-Dec-13, 01:50 PM
The point of convergent evolution is that the same solution is found by unrelated species. That's not an argument for it being another mammal next time.

tnjrp
2011-Dec-13, 02:01 PM
If humans did become extinct and one came back 65 million years from now to find that not only had no dominant or intelligent species evolved, but that all flora and fauna were exactly the same as today, would we say that 1) the theory of evolution is incorrect, 2) our interpretation of it is incorrect, or 3) evolution has ceased, and right now is as good as it gets?Mind games are fun but only if there is no agenda involved.

I have a funny one for you: where to you get when you go north from North Pole?


Is no smidgen of speciation, macro-evolution or new organs at all over the next 65 million years from now a conceivable scenario?(1) Speciation (or "level I macroevolution" if you prefer) has been observed and it's not likely to stop.
(2) Define "macro-evolution".
(3) Define "new organs".

KaiYeves
2011-Dec-14, 12:28 AM
Is it creepy that I have wondered the question posed by the thread title several times?

Buzz-Lite-Punch
2011-Dec-14, 12:50 AM
There's no particular reason any species would "succeed" us, I.E. become sentient tool-users with civilization. Evolution doesn't work that way.

As for the accuracy of dinosaur behavior in JP, it was probably about as accurate as their appearance.

I think its done for dramatic licence of T-Rex eating man while relieving himself on a toilet. :rofl: LOL Noo, noo Roarrrrr!! Aghhhhh!

Well one things for sure! We won’t be around to know.
I hope cats rule the planet I’m a cat owner and I think cats and dogs should be living together.

I mean what have we’ve done in million years or so. I tell you what we’ve done, More death and destruction that creating life. It’s no wonder there is so much bitterness and hate in the world between neighbouring counties. It’s just going to continue on and on. We’re the givers of our own demise and who knows, ole Nos might be spot in December 2012?

As to what killed the dinosaurs it could be maybe a meteor or something different? We have only vague understanding not total concrete proof because “we” weren’t even around to record the last days of the dinosaurs. Maybe it one eat plant and spread a bad news disease around to the other dinosaurs. Speculation is all, it is. Who knows maybe aliens killed the dinosaurs and I’m sure Hollywood would get excited about that make 3D movies about it.

Yeah its sad they were wiped out but they had good life and so have we, until we wipe each other out. And who will be around to recoded our existence? No one! Expect a travelling probe called Voyage 1 and 2.

As for cats my cat stares at me and I know he is studying me, my behaviour my mood my fingers arms moving around any verbal words that he might like and he’ll respond back to me, with meow, lots of meow.
Yes cats could dominate the world along with dogs.

Sardonicone
2011-Dec-14, 12:53 AM
Is it creepy that I have wondered the question posed by the thread title several times?

No, because then that would make the fact I also do it Creepy.

I would consider Chimps to have a very real shot at this, but I fear we're getting close to not having a large enough beding population for that to happen. Rats are extremely intelligent, however their shortened lifespan and current size puts them at a severe disadvantage. Now, granted the rise of mammals happened with all of us basically being rat/shrew like beings...so perhaps given enough time that isn't enough to rule them out.

Meercats are cute. On that alone, I vote for them.

Buzz-Lite-Punch
2011-Dec-14, 01:15 AM
No, because then that would make the fact I also do it Creepy.

I would consider Chimps to have a very real shot at this, but I fear we're getting close to not having a large enough beding population for that to happen. Rats are extremely intelligent, however their shortened lifespan and current size puts them at a severe disadvantage. Now, granted the rise of mammals happened with all of us basically being rat/shrew like beings...so perhaps given enough time that isn't enough to rule them out.

Meercats are cute. On that alone, I vote for them.

Yeah they’re plenty of rats in New York at the local KFC which proves intelligence. They like 4 Big Macs 6 fries and 4 milk shakes.
:D
Rats no leave it out. I have only ever seen one rat crossing the road running away from Pizza restaurant 12 years ago and the size of it! I bet he was living off that restaurant, it had it made.

wd40
2011-Dec-14, 12:22 PM
Because of convergent evolution I think it will be another mammal. My money is on the racoons.

Judging by this, if paw/hand dexterity is a requisite for the evolution of intelligence the "thieving racoon" has a head start! http://www.youtube.com/watch?v=_SOJ4y0PXm4

Solfe
2011-Dec-15, 02:59 AM
Is it creepy that I have wondered the question posed by the thread title several times?

A comedian once said that when we are all long gone, only Keith Richards will be around to step on the cockroaches. Darned if I can remember who said that, it is really funny.

Gillianren
2011-Dec-15, 03:12 AM
It's not exactly original.

Solfe
2011-Dec-15, 03:15 AM
Little of my knowledge base is. :)

JCoyote
2011-Dec-15, 05:22 PM
Well I would consider one important factor if mankind disappeared relatively abruptly that no one here has considered...

An accurate statement has been made that evolution doesn't particularly favor intelligence or opposable thumbs as goals and that's true in a relative vacuum, but there is a major factor here that gives preference.

Let's say a disease wipes out humans over the course of a couple years. We would leave a world full of shelters and tools fit to certain body types. This would leave a strong selection bias toward features that would help fill the same niche.

And actually raccoons do live in the shadow of human habitats without being domesticated and readily learn human tools and behaviors. That would place them as front runners because odds are they would be the first in line to move into our abandoned homes.

It's not terribly unreasonable to come up with a list of species that would be front runners for taking advantage of things we'd leave behind... those things do provide advantage after all.

HenrikOlsen
2011-Dec-15, 05:30 PM
It's not terribly unreasonable to come up with a list of species that would be front runners for taking advantage of things we'd leave behind... those things do provide advantage after all.
The OP stipulated 65 million years, very little left-over human stuff will last for that long or even for the shortness of time humans have been around.

The vast majority of species living in our shadow does so because of easy access to wasted food, besides the artificial recreation of their natural habitat.

With humans gone, so is the food.

JCoyote
2011-Dec-15, 07:09 PM
The OP stipulated 65 million years, very little left-over human stuff will last for that long or even for the shortness of time humans have been around.

The vast majority of species living in our shadow does so because of easy access to wasted food, besides the artificial recreation of their natural habitat.

With humans gone, so is the food.

65 million years later is a bit irrelevant. A few thousand years of selective pressure into an unopposed ecological niche will have long term impacts on a species. The results of evolutionary pressure do not disappear tomorrow.

Once the foothold is gained it won't be abandoned if advantageous. If mild capacities of replication and then innovation occur, ie the ability to make say knives and other simple implements, and later to improve on their own versions, then the cycle is self-sustaining. Short term pressures on species can lead to lasting changes if the outcome if more generally advantageous.

And with humans gone, so is the reason to stay on the edge of our habitats. And not all humans live in cities, plenty of humans live in places with ready access to natural food sources, turning their abandoned shelters into prime real estate for any species that can use it. And yes, foodless abandoned cabins in the woods are often food to have animals inhabiting them, often raccoons.

Gillianren
2011-Dec-15, 08:03 PM
It's also worth noting that no single species has ever dominated the planet for terribly long. "Dinosaurs," okay, but "dinosaurs" covers a lot of territory. We haven't been around very long as a species, and it can't even be said that mammals have dominated since dinosaurs were wiped out; birds had a pretty good run, I've read. In 65 million years, we won't recognize whatever species is in charge, even if it's our own descendants. At least almost certainly not. To assume the planet will be controlled by a species that exists today is to fail to understand all the processes involved. After all, another asteroid of the size that killed the dinosaurs is as likely as not some time in the next 65 million years.

transreality
2011-Dec-15, 11:16 PM
We haven't been around very long as a species, and it can't even be said that mammals have dominated since dinosaurs were wiped out; birds had a pretty good run, I've read.

wiki: paleocene (http://en.wikipedia.org/wiki/Paleocene)

"While early mammals were small nocturnal animals that mostly ate soft plant material and small animals such as insects, the demise of the non-avian dinosaurs and the beginning of the Paleocene saw mammals growing bigger and occupying a wider variety of ecological niches. Ten million years after the death of the non-avian dinosaurs, the world was filled with rodent-like mammals, medium sized mammals scavenging in forests, and large herbivorous and carnivorous mammals hunting other mammals, birds, and reptiles."

There were some big carnivorous birds in the Paleocene, but by the Eocene they are restricted to isolated habitats. Possibly New Zealand, and some other isolated islands represent what a world where mammals did not dominate most terrestrial niches, and as a consequence ground dwelling birds are much more diverse. The Eocene is pretty much defined by the appearance of modern mammal groups.