50 replies to this topic

[Roj47]

This may be a bit basic, but I can not find anything particularly conclusive on the net.

What was it that actually allowed certain dinosaurs to grow to immense sizes. Agreed there is the whale by todays standard, but was it oxygen levels? available food? purely time available to evolve? or a combination of these and other elements.

Should humans be able to hold the Earth for 135 million years. Would you expect us to grow to larger sizes as to some extent we are now, or as a genus are we limited to our growth potential?

regards

[Essan]

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This may be a bit basic, but I can not find anything particularly conclusive on the net.

What was it that actually allowed certain dinosaurs to grow to immense sizes. Agreed there is the whale by todays standard, but was it oxygen levels? available food? purely time available to evolve? or a combination of these and other elements.

A combination of those factors, plus a relatively stable climate.  Also, given stable conditions and adequate food supplies, herbivores tend to grow bigger as a defence against carnivores.  Who then grow bigger in order to be able to kill the bigger herbivores.  And so on.  Eventually a limit is reached, or else climate changes change the rules of the game.

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Should humans be able to hold the Earth for 135 million years. Would you expect us to grow to larger sizes as to some extent we are now, or as a genus are we limited to our growth potential?

On average we're several inches taller and rather a lot of pounds heavier than 100 years ago.  I doubt we'll end up being 20ft tall though.   20ft round the waist maybe?    

[Raptor]

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This may be a bit basic, but I can not find anything particularly conclusive on the net.

What was it that actually allowed certain dinosaurs to grow to immense sizes. Agreed there is the whale by todays standard, but was it oxygen levels? available food? purely time available to evolve? or a combination of these and other elements.

Like what Essan said, there was an evolutionary need to grow larger, herbivores for defense, carnivores for hunting. They were allowed to do so for the reasons you mentioned, oxygen and food.

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Should humans be able to hold the Earth for 135 million years. Would you expect us to grow to larger sizes as to some extent we are now, or as a genus are we limited to our growth potential?

regards

No. Unlike with the dinosaurs, we have no reason to grow larger.

Edited by Raptor X7, 05 September 2006 - 12:26 PM.

[frogfish]

Basically it's their niche and ecosystem. The ecosystem allowed them to grow that big.

[Twitch98]

For me a better question is why have human and proto-humans progressed in intelligence at an unprecidented rate when no other species, even those such as the dinosours around for eons longer, were able to?

[frogfish]

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For me a better question is why have human and proto-humans progressed in intelligence at an unprecidented rate when no other species, even those such as the dinosours around for eons longer, were able to?

It's just pure chance and evolution. To survive, we needed to gain intelligence. After that, we kind of took it into our own hands.

[Twitch98]

I might accept that if humans were one species.  The problem is that EVERY hominid species developed in intelligence exponentially branching off and accelerating from a brain no more complex than your average dinosaur.  Whatever cause that I'd like to know.

[Raptor]

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I might accept that if humans were one species.  The problem is that EVERY hominid species developed in intelligence exponentially branching off and accelerating from a brain no more complex than your average dinosaur.  Whatever cause that I'd like to know.

Well that would suggest that the common ancestor of modern hominids gained intelligence through the means that frogfish posted.

[the_h0llow_earth]

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For me a better question is why have human and proto-humans progressed in intelligence at an unprecidented rate when no other species, even those such as the dinosours around for eons longer, were able to?

In reality we don't know how smart dinosaurs were.  Scientists measure dinosaurs EQ (Encephalization Quotient) to try and find out how smart dinosaurs were.  EQ is the ratio of the brain weight of the animal to the brain weight of an animal of the same body weight.  So the intelligence of dinosaurs is measured assuming that smarter animals have larger brains, which is not a proven fact.  Dinosaurs may have been very intelligent, but they obviously could not build anything because of the way their bodies were.  The point is there is no sure way to tell how smart they were.

[Twitch98]

Well yeah there is a way to tell how intelligent dinos were.  The physical brain size is the universal key factor to intelligence in relation to the body.  Cranial capacity of dinos was immense but the actual size of the brain was small.  Imprints of brains inside of fossilized skulls have confirmed that.  There was no possible way that they had abstract thought or perspective and most importantly they were not tool users.

Frogfish is correct in that the dinos adapted to their ecosystem in evolutionary terms.  Early humans had brainpower to compensate for size and power so hominids didn't grow large.

Animals do amaze us when we see how perfectly they fill niches and adapt to enviromnents.  Being an efficient species doesn't guarantee high intelligence but simply a solid place in the food chain.

Of course if we really split hairs humans have actually increased in physical stature over just the last millenium.  Our average height and weight is far more than it was 1,000 years ago.

[frogfish]

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Animals do amaze us when we see how perfectly they fill niches and adapt to enviromnents.

When the space is there, they evolve...Especially after extinctions.

More proof of punctuated equilibrium.

[the_h0llow_earth]

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Well yeah there is a way to tell how intelligent dinos were.  The physical brain size is the universal key factor to intelligence in relation to the body.  Cranial capacity of dinos was immense but the actual size of the brain was small.  Imprints of brains inside of fossilized skulls have confirmed that.  There was no possible way that they had abstract thought or perspective and most importantly they were not tool users.

So midgets must be super intelligent!  

[Startraveler]

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Should humans be able to hold the Earth for 135 million years. Would you expect us to grow to larger sizes as to some extent we are now, or as a genus are we limited to our growth potential?

My paleontology professor introduced me to a very interesting famous essay that you might enjoy: J.B.S. Haldane's "On being the right size".

Edited by Startraveler, 10 September 2006 - 04:59 PM.

[Twitch98]

Since dwarves, midgets and giants are abberent they do not factor in.  Human infants have large brains relative to their size also but no one is drawing a conclusion that they are more intelligent than adults.

[Lord Umbarger]

Of course, if a species of dinosaur were to reach a decent level of intelligence, how would we know? What would they leave behind? Would we recognise tools that were designed by another thought process and to be used by hands with a different number of fingers? What will be left of human civilization in 65 milions years if we were to all vanish today? Would a species of advanced bees recognise the importance of a hammer or a spear point?

No traces of firemastery would remain from that time and even if it did, finding it would be next to impossible, right?

Then again, there is the question of enviroment making one smarter. Judging by the body to brain mass equation, how smart would you have to be to be the smartest thing on earth if your only compitition was an overgrown chicken? (...in the land of the blind the one eyed man is king?). What would compell evolution to waste brain power on a creature when all it had to do was listen and smell to find food and safety?

Before you poo-poo this thought, one can still find roaches in a chicken coop.