Dinosaurs 'shrank' regularly to become birds (1 Viewer)

Huge meat-eating, land-living dinosaurs evolved into birds by constantly shrinking for over 50 million years, scientists have revealed.

Theropods shrunk 12 times from 163kg (25st 9lb) to 0.8kg (1.8lb), before becoming modern birds.

The researchers found theropods were the only dinosaurs to get continuously smaller.

Their skeletons also changed four times faster than other dinosaurs, helping them to survive.

Results from the study are reported in the journal Science.

Continue reading the main story From dinosaur to bird
Previous work has shown that theropod dinosaurs, the dinosaur group which included Tyrannosaurus rex and Velociraptor and gave rise to modern birds, must have decreased in size at some point in their evolution into small, agile flyers.

But size changes frequently occurred in dinosaur evolution, so the research team members, led by Mike Lee, from the University of Adelaide, Australia, wanted to find out if the dramatic size reduction associated with the origin of birds was unique.

They also wanted to measure the rate of evolution in dinosaurs using a large data set.

The authors used sophisticated analytical tools - developed by molecular biologists trying to understand virus evolution - to study more than 1,500 dinosaur body traits coded from 120 well-documented species of theropod and early birds.

From this analysis they produced a detailed family tree mapping out the transformation of theropods to their bird descendants.

It traces evolving adaptations and changing body size over time and across dinosaur branches.

They found that the dinosaur group directly related to birds shrank rapidly from about 200 million years ago.

It showed a decrease in body mass of 162.2kg (25st 7lb) from the largest average body size to Archaeopteryx, the earliest known bird.

These bird ancestors also evolved new adaptations, including feathers, wishbones and wings, four times faster than other dinosaurs.

Shrinking and new bird-like traits jointly influenced the transition of dinosaurs to birds, researchers say.
The researchers concluded that the evolution of the branch of dinosaurs leading to birds was more innovative than other dinosaur lineages.

The authors say this sustained shrinking and accelerated evolution of smaller and smaller body size allowed the ancestors of birds to develop traits which helped them to cope much better than their less evolved dinosaur relatives.

"Birds evolved through a unique phase of sustained miniaturisation in dinosaurs," Mr Lee said.

"Being smaller and lighter in the land of giants, with rapidly evolving anatomical adaptations, provided these bird ancestors with new ecological opportunities, such as the ability to climb trees, glide and fly.

"Ultimately, this evolutionary flexibility helped birds survive the deadly meteorite impact which killed off all their dinosaurian cousins."

'No overnight transformation'The researchers believe that miniaturisation and the development of bird-like traits had a joint influence on the evolution of the dinosaurs into today's birds.

Professor Michael Benton, from the University of Bristol's school of earth sciences, said: "This study means we can't see the origin of birds as a sudden or dramatic event, with a dinosaur becoming a powered flyer overnight.

"The functions of each special feature of birds changed over time - feathers first for insulation, and later co-opted for flight; early reductions in body size perhaps for other reasons, and later they were small enough for powered flight; improvements in sense of sight and enlargement of brain - even a small improvement in these is advantageous.

"So perhaps it's a long-term trend associated with deputation to a new set of habitats, in the trees, to avoid predation, and to exploit new food resources."

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Ditka Butkus said:

bull####

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lod01 said:

Pretty ridiculous. I know we are talking about millions of years but I find it hard to believe that small reptiles mutate into giant dinosaurs and then into birds.

If we get hit with an extinction level asteroid what the hell will we become?

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lod01 said:

Maybe we evolved from birds and my great grandfather x2,500,000 was a T-Rex.

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bostonfred said:

Same thing that happened with the evolution of wings. Yes, things happened over a long period of time. Yes, small advantages select themselves over time. But why woulda smaller skeletal structure or a tiny flap of skin be advantageous enough to select itself into the species? The obvious answer seems to be that it wouldn't. And the obvious answer is correct.

As a predecessor to a wing or some ability to glide, a tiny flap of skin would be virtually worthless on its own. There is absolutely no reason for the species to select it. Of course, the species doesn't select the trait. It's not like there's some tribal council that says, here here, point of order, the next order of business is that we need to figure out what we want to do with this flap. I say keep it! All those in favor say aye. Instead, what happens is that, one day, a lizard has a weird flap. The other lizards don't pick on him for it because they probably don't notice it. And neither does he. But the good news for him - and for millions of future birdwatchers - is that, like most lizards, he has sex whenever possible, and some - but not all - of their baby lizards have a tiny weird flap just like daddy did.

Now for the sad part of the story: Some of those lizards die. The lizards that die do absolutely nothing to pass on their genetic material. But the ones that live continue to have sex, and some of their offspring also have the weird flap. Not a bigger flap, just the same tiny, meaningless, doesn't-help-in-any-meaningful-way flap in their armpit or between their fingers or whatever. And slowly but surely, some of the flap-havers mate with flapless lizards and their children have a mix of flap and no flap. A hundred years later, in an area with tens of thousands of these little lizards, a few hundred of the great great great great great great great grandchildren of the original flap lizard have flaps. And they've done nothing at all to help those lizards survive. These distant cousins were fortunate enough to survive because they were lizards, not because they had flaps.

But in just a hundred years, a mutation has spread throughout the population. Not to everyone, just to a small group of the lizards. The first lizard that had flaps had sex with lizards that didn't have flaps and after a few generations, some of their kids and grandkids had flaps, and so on. No evolutionary advantage required.

So over a few generations, the Flap family has grown. Now expand that from a hundred years to a thousand years, and some kids have bigger flaps, while others have smaller flaps. Still very small flaps, and hardly meaningful, but there are many lizards with tiny flaps in their armpit, and there's nothing killing them off any faster than their peers so they keep on procreating.

But this is clearly not the only lizard family in the world. There are lots of other lizards. And one of those other lizards gets a weird mutation: a bump on his left shoulder. And the lizard with the bump on his shoulder also has kids, and grandkids, and so on. And some of them have bumps. Some of their bumps are over their left shoulder, some are on the neck, some are bigger, some are smaller. And many generations later, in the whole population of lizards, the Bump family tree is about the same size as the Flap family tree. But you've probably never heard of the Bump-kin, because, like most mutations, they didn't really add any value to the family tree. The same goes for the lizards that had a weird brown blotch on their foot, or the ones with the sligthly bluer skin tone, or the ones with the yellower looking eyeballs. Sometimes lizard kids look weird, but they have sex, and their family tree looks a little weirder because of it.

Similarly, you may notice that your second cousins look more like your great aunts and uncles than your grandparents. Or maybe they look like you, because you both kind of resemble your great grandparents. We've come to expect that tall parents have tall kids and redheads have redheaded kids and people with big noses have kids with big noses, although we alos know that not every trait gets passed down, and some traits skip a generation, or stay on the female side of the family, and so on. The same was true with the lizards. And just like redheads haven't been selected in, neither have they been selected out at this point, so redheads and blondes coexist. And even if there were any kind of evolutionary pressure - for example, if gentlemen really did prefer blondes - the invention of hair dye makes it far less likely that future generations of human will be all blonde, or all brunette, or all redheaded.

So getting back to the flap family - they really didn't make any particular progress, but it didn't fall behind, either. A thousand years have gone by, and there are a lot of lizards with little flaps under their arms, and those lizards aren't jumping much further than their flapless counterparts at all. Over time, the mutation - flaps - is just part of what they look like. And, like any other trait, some of their flaps are bigger, some are smaller. And some of the brown spotted foot lizards have big brown spots and some have little brown spots. And some of the slightly bluer lizards are extra blue while others are greener. All these families are alive and kicking after a thousand years.

Ten thousand years, though, is a long time, and a lot of lizards have had a lot of sex during this time. And during this time, everyone has forgotten the father of the flap family. But by now, the variation in the size of the flaps is noticable. Some are just a millimeter, while others are closer to a centimeter. If you put them side by side, you'd be able to clearly see a difference. And you'd still have a large number of lizards with no flaps whatsoever, because, at this point, there still isn't an evolutionary advantage to having flaps. But the percentage of flaps versus no flaps would still be growing, because the flap family keeps having sex with the flapless, and there's all kinds of intermingling with cousins going on, and who can blame them. They're hot blooded animals.

All of this might be happening over the course of thousands of years, before the first lizards have flaps big enough to meaningfully change their ability to jump. And even then, it's not like those jumping lizards win a prize. At this point, the jumping lizards might be the cool kids in school, but still, the "species" hasn't selected any kind of trait. It's just that some lizards are able to jump further than others.

Meanwhile, just like the flaps and the brown spots and the blue skins, other families of lizards have had heavier and lighter bones. Again, there's nothing specific about light boned lizards that makes them live longer, although this trait has a little more to do with which lizards live and which die. Maybe some of them can climb up a skinny little branch to get to a leaf without the branch bending over and knocking them down, which means that more of them are able to eat enough to survive. Or maybe others tend to die before they can mate because they have a glass jaw. But when we're talking about small fluctuations in bone density, there's going to be some fat looking lizards that keep saying they're just big boned, and skinny lizards with lighter bones.

And out of all those lizards, the skinny lizards with light bones and big flaps seem to be able to jump the furthest. And by the furthest, I mean maybe a couple inches further than their counterparts.

Of course, with all these lizards having sex, you'd think the world would be overrun by lizards. But it isn't, because those lizards have predators eating them. And there's only so much food to go around. Out of a generation of a million lizards, maybe only a hundred thousand live long enough to have sex and pass their genes on to the next generation. And up until recently, the odds of a flap-having lizard surviving were almost identical to the odds of a flapless lizard surviving. But things have changed. Now the flap lizards - and especially the skinny, light boned ones with the biggest flaps - are able to jump far enough that it makes a difference. They can get from one plant to the next just a little faster, so when a bunch of lizards are fighting over a small amount of food, they eat first. When a predator is climbing a tree to catch them, they can jump just a little further than their peers. The odds of lizard survival are greater if they're skinny, have lighter bones and bigger flaps, so more and more lizards will have that trait.

But what about the fatties? Do they all die? Maybe. Or maybe not. Maybe some of the chunky lizards with big bones and thick skin are able to survive the first punch a little better than their light boned counterparts. Maybe the ones with slightly browner skin tone are able to hide on tree bark, and the ones with slightly greener skin tone are able to hide on leaves, and avoid predators altogether. So the green lizards and brown lizards and big boned lizards and skinny light bones lizards with big flaps all tend to live long enough to have kids, while the others tend to die off more often. There are still skinny lizards with heavy bones and fat lizards with flaps and bluer skinned lizards and so on, but with each generation, there are fewer and fewer of them. And over the course of ten thousand more years, this becomes noticable.

And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more.

So now a hundred thousand years have passed, and we've started to see that the bigger the flaps, the lighter the bones, and the skinnier they were, the more they survived. Along the way, maybe they mated with other lizards, too, and some of those may have had desirable traits. Lighter skin might have been desirable for the jumping and gliding, but not so much for survival. But some of these new lizards have really light scales that fold one over the other, the early predecessors of feathers. And that was even lighter than the other lizards. But the same feature wasn't much help to the fat lizards with big heavy bones or the brown lizards or the green lizards, and in fact, those lizards lived longer when they had thicker skin that didn't tear as easily when a predator attacked.

So we start to get speciation. Skinny lizards with light bones and big flaps under their arms and feather like scales lived longer than skinny lizards with heavy bones or heavy lizards with light bones or any other combinations. And over the course of a million years, while they've inherited a substantial number of traits from their great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great grandparents, they bear very little resemblance to them, just like you probably don't look exactly like your grandfather, or your great grandfather, and even less like your great great great great grandfather, and so on.

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Ditka Butkus said:

See this is an example why I went with the simple bull####.....

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bostonfred said:

Same thing that happened with the evolution of wings. Yes, things happened over a long period of time. Yes, small advantages select themselves over time. But why woulda smaller skeletal structure or a tiny flap of skin be advantageous enough to select itself into the species? The obvious answer seems to be that it wouldn't. And the obvious answer is correct.

As a predecessor to a wing or some ability to glide, a tiny flap of skin would be virtually worthless on its own. There is absolutely no reason for the species to select it. Of course, the species doesn't select the trait. It's not like there's some tribal council that says, here here, point of order, the next order of business is that we need to figure out what we want to do with this flap. I say keep it! All those in favor say aye. Instead, what happens is that, one day, a lizard has a weird flap. The other lizards don't pick on him for it because they probably don't notice it. And neither does he. But the good news for him - and for millions of future birdwatchers - is that, like most lizards, he has sex whenever possible, and some - but not all - of their baby lizards have a tiny weird flap just like daddy did.

Now for the sad part of the story: Some of those lizards die. The lizards that die do absolutely nothing to pass on their genetic material. But the ones that live continue to have sex, and some of their offspring also have the weird flap. Not a bigger flap, just the same tiny, meaningless, doesn't-help-in-any-meaningful-way flap in their armpit or between their fingers or whatever. And slowly but surely, some of the flap-havers mate with flapless lizards and their children have a mix of flap and no flap. A hundred years later, in an area with tens of thousands of these little lizards, a few hundred of the great great great great great great great grandchildren of the original flap lizard have flaps. And they've done nothing at all to help those lizards survive. These distant cousins were fortunate enough to survive because they were lizards, not because they had flaps.

But in just a hundred years, a mutation has spread throughout the population. Not to everyone, just to a small group of the lizards. The first lizard that had flaps had sex with lizards that didn't have flaps and after a few generations, some of their kids and grandkids had flaps, and so on. No evolutionary advantage required.

So over a few generations, the Flap family has grown. Now expand that from a hundred years to a thousand years, and some kids have bigger flaps, while others have smaller flaps. Still very small flaps, and hardly meaningful, but there are many lizards with tiny flaps in their armpit, and there's nothing killing them off any faster than their peers so they keep on procreating.

But this is clearly not the only lizard family in the world. There are lots of other lizards. And one of those other lizards gets a weird mutation: a bump on his left shoulder. And the lizard with the bump on his shoulder also has kids, and grandkids, and so on. And some of them have bumps. Some of their bumps are over their left shoulder, some are on the neck, some are bigger, some are smaller. And many generations later, in the whole population of lizards, the Bump family tree is about the same size as the Flap family tree. But you've probably never heard of the Bump-kin, because, like most mutations, they didn't really add any value to the family tree. The same goes for the lizards that had a weird brown blotch on their foot, or the ones with the sligthly bluer skin tone, or the ones with the yellower looking eyeballs. Sometimes lizard kids look weird, but they have sex, and their family tree looks a little weirder because of it.

Similarly, you may notice that your second cousins look more like your great aunts and uncles than your grandparents. Or maybe they look like you, because you both kind of resemble your great grandparents. We've come to expect that tall parents have tall kids and redheads have redheaded kids and people with big noses have kids with big noses, although we alos know that not every trait gets passed down, and some traits skip a generation, or stay on the female side of the family, and so on. The same was true with the lizards. And just like redheads haven't been selected in, neither have they been selected out at this point, so redheads and blondes coexist. And even if there were any kind of evolutionary pressure - for example, if gentlemen really did prefer blondes - the invention of hair dye makes it far less likely that future generations of human will be all blonde, or all brunette, or all redheaded.

So getting back to the flap family - they really didn't make any particular progress, but it didn't fall behind, either. A thousand years have gone by, and there are a lot of lizards with little flaps under their arms, and those lizards aren't jumping much further than their flapless counterparts at all. Over time, the mutation - flaps - is just part of what they look like. And, like any other trait, some of their flaps are bigger, some are smaller. And some of the brown spotted foot lizards have big brown spots and some have little brown spots. And some of the slightly bluer lizards are extra blue while others are greener. All these families are alive and kicking after a thousand years.

Ten thousand years, though, is a long time, and a lot of lizards have had a lot of sex during this time. And during this time, everyone has forgotten the father of the flap family. But by now, the variation in the size of the flaps is noticable. Some are just a millimeter, while others are closer to a centimeter. If you put them side by side, you'd be able to clearly see a difference. And you'd still have a large number of lizards with no flaps whatsoever, because, at this point, there still isn't an evolutionary advantage to having flaps. But the percentage of flaps versus no flaps would still be growing, because the flap family keeps having sex with the flapless, and there's all kinds of intermingling with cousins going on, and who can blame them. They're hot blooded animals.

All of this might be happening over the course of thousands of years, before the first lizards have flaps big enough to meaningfully change their ability to jump. And even then, it's not like those jumping lizards win a prize. At this point, the jumping lizards might be the cool kids in school, but still, the "species" hasn't selected any kind of trait. It's just that some lizards are able to jump further than others.

Meanwhile, just like the flaps and the brown spots and the blue skins, other families of lizards have had heavier and lighter bones. Again, there's nothing specific about light boned lizards that makes them live longer, although this trait has a little more to do with which lizards live and which die. Maybe some of them can climb up a skinny little branch to get to a leaf without the branch bending over and knocking them down, which means that more of them are able to eat enough to survive. Or maybe others tend to die before they can mate because they have a glass jaw. But when we're talking about small fluctuations in bone density, there's going to be some fat looking lizards that keep saying they're just big boned, and skinny lizards with lighter bones.

And out of all those lizards, the skinny lizards with light bones and big flaps seem to be able to jump the furthest. And by the furthest, I mean maybe a couple inches further than their counterparts.

Of course, with all these lizards having sex, you'd think the world would be overrun by lizards. But it isn't, because those lizards have predators eating them. And there's only so much food to go around. Out of a generation of a million lizards, maybe only a hundred thousand live long enough to have sex and pass their genes on to the next generation. And up until recently, the odds of a flap-having lizard surviving were almost identical to the odds of a flapless lizard surviving. But things have changed. Now the flap lizards - and especially the skinny, light boned ones with the biggest flaps - are able to jump far enough that it makes a difference. They can get from one plant to the next just a little faster, so when a bunch of lizards are fighting over a small amount of food, they eat first. When a predator is climbing a tree to catch them, they can jump just a little further than their peers. The odds of lizard survival are greater if they're skinny, have lighter bones and bigger flaps, so more and more lizards will have that trait.

But what about the fatties? Do they all die? Maybe. Or maybe not. Maybe some of the chunky lizards with big bones and thick skin are able to survive the first punch a little better than their light boned counterparts. Maybe the ones with slightly browner skin tone are able to hide on tree bark, and the ones with slightly greener skin tone are able to hide on leaves, and avoid predators altogether. So the green lizards and brown lizards and big boned lizards and skinny light bones lizards with big flaps all tend to live long enough to have kids, while the others tend to die off more often. There are still skinny lizards with heavy bones and fat lizards with flaps and bluer skinned lizards and so on, but with each generation, there are fewer and fewer of them. And over the course of ten thousand more years, this becomes noticable.

And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more.

So now a hundred thousand years have passed, and we've started to see that the bigger the flaps, the lighter the bones, and the skinnier they were, the more they survived. Along the way, maybe they mated with other lizards, too, and some of those may have had desirable traits. Lighter skin might have been desirable for the jumping and gliding, but not so much for survival. But some of these new lizards have really light scales that fold one over the other, the early predecessors of feathers. And that was even lighter than the other lizards. But the same feature wasn't much help to the fat lizards with big heavy bones or the brown lizards or the green lizards, and in fact, those lizards lived longer when they had thicker skin that didn't tear as easily when a predator attacked.

So we start to get speciation. Skinny lizards with light bones and big flaps under their arms and feather like scales lived longer than skinny lizards with heavy bones or heavy lizards with light bones or any other combinations. And over the course of a million years, while they've inherited a substantial number of traits from their great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great grandparents, they bear very little resemblance to them, just like you probably don't look exactly like your grandfather, or your great grandfather, and even less like your great great great great grandfather, and so on.

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Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

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Dan Gladden said:

Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

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It's nice to see someone so proud of their ignorance.

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lod01 said:

Pretty ridiculous. I know we are talking about millions of years but I find it hard to believe that small reptiles mutate into giant dinosaurs and then into birds.

If we get hit with an extinction level asteroid what the hell will we become?

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bostonfred said:

Same thing that happened with the evolution of wings. Yes, things happened over a long period of time. Yes, small advantages select themselves over time. But why woulda smaller skeletal structure or a tiny flap of skin be advantageous enough to select itself into the species? The obvious answer seems to be that it wouldn't. And the obvious answer is correct.

As a predecessor to a wing or some ability to glide, a tiny flap of skin would be virtually worthless on its own. There is absolutely no reason for the species to select it. Of course, the species doesn't select the trait. It's not like there's some tribal council that says, here here, point of order, the next order of business is that we need to figure out what we want to do with this flap. I say keep it! All those in favor say aye. Instead, what happens is that, one day, a lizard has a weird flap. The other lizards don't pick on him for it because they probably don't notice it. And neither does he. But the good news for him - and for millions of future birdwatchers - is that, like most lizards, he has sex whenever possible, and some - but not all - of their baby lizards have a tiny weird flap just like daddy did.

Now for the sad part of the story: Some of those lizards die. The lizards that die do absolutely nothing to pass on their genetic material. But the ones that live continue to have sex, and some of their offspring also have the weird flap. Not a bigger flap, just the same tiny, meaningless, doesn't-help-in-any-meaningful-way flap in their armpit or between their fingers or whatever. And slowly but surely, some of the flap-havers mate with flapless lizards and their children have a mix of flap and no flap. A hundred years later, in an area with tens of thousands of these little lizards, a few hundred of the great great great great great great great grandchildren of the original flap lizard have flaps. And they've done nothing at all to help those lizards survive. These distant cousins were fortunate enough to survive because they were lizards, not because they had flaps.

But in just a hundred years, a mutation has spread throughout the population. Not to everyone, just to a small group of the lizards. The first lizard that had flaps had sex with lizards that didn't have flaps and after a few generations, some of their kids and grandkids had flaps, and so on. No evolutionary advantage required.

So over a few generations, the Flap family has grown. Now expand that from a hundred years to a thousand years, and some kids have bigger flaps, while others have smaller flaps. Still very small flaps, and hardly meaningful, but there are many lizards with tiny flaps in their armpit, and there's nothing killing them off any faster than their peers so they keep on procreating.

But this is clearly not the only lizard family in the world. There are lots of other lizards. And one of those other lizards gets a weird mutation: a bump on his left shoulder. And the lizard with the bump on his shoulder also has kids, and grandkids, and so on. And some of them have bumps. Some of their bumps are over their left shoulder, some are on the neck, some are bigger, some are smaller. And many generations later, in the whole population of lizards, the Bump family tree is about the same size as the Flap family tree. But you've probably never heard of the Bump-kin, because, like most mutations, they didn't really add any value to the family tree. The same goes for the lizards that had a weird brown blotch on their foot, or the ones with the sligthly bluer skin tone, or the ones with the yellower looking eyeballs. Sometimes lizard kids look weird, but they have sex, and their family tree looks a little weirder because of it.

Similarly, you may notice that your second cousins look more like your great aunts and uncles than your grandparents. Or maybe they look like you, because you both kind of resemble your great grandparents. We've come to expect that tall parents have tall kids and redheads have redheaded kids and people with big noses have kids with big noses, although we alos know that not every trait gets passed down, and some traits skip a generation, or stay on the female side of the family, and so on. The same was true with the lizards. And just like redheads haven't been selected in, neither have they been selected out at this point, so redheads and blondes coexist. And even if there were any kind of evolutionary pressure - for example, if gentlemen really did prefer blondes - the invention of hair dye makes it far less likely that future generations of human will be all blonde, or all brunette, or all redheaded.

So getting back to the flap family - they really didn't make any particular progress, but it didn't fall behind, either. A thousand years have gone by, and there are a lot of lizards with little flaps under their arms, and those lizards aren't jumping much further than their flapless counterparts at all. Over time, the mutation - flaps - is just part of what they look like. And, like any other trait, some of their flaps are bigger, some are smaller. And some of the brown spotted foot lizards have big brown spots and some have little brown spots. And some of the slightly bluer lizards are extra blue while others are greener. All these families are alive and kicking after a thousand years.

Ten thousand years, though, is a long time, and a lot of lizards have had a lot of sex during this time. And during this time, everyone has forgotten the father of the flap family. But by now, the variation in the size of the flaps is noticable. Some are just a millimeter, while others are closer to a centimeter. If you put them side by side, you'd be able to clearly see a difference. And you'd still have a large number of lizards with no flaps whatsoever, because, at this point, there still isn't an evolutionary advantage to having flaps. But the percentage of flaps versus no flaps would still be growing, because the flap family keeps having sex with the flapless, and there's all kinds of intermingling with cousins going on, and who can blame them. They're hot blooded animals.

All of this might be happening over the course of thousands of years, before the first lizards have flaps big enough to meaningfully change their ability to jump. And even then, it's not like those jumping lizards win a prize. At this point, the jumping lizards might be the cool kids in school, but still, the "species" hasn't selected any kind of trait. It's just that some lizards are able to jump further than others.

Meanwhile, just like the flaps and the brown spots and the blue skins, other families of lizards have had heavier and lighter bones. Again, there's nothing specific about light boned lizards that makes them live longer, although this trait has a little more to do with which lizards live and which die. Maybe some of them can climb up a skinny little branch to get to a leaf without the branch bending over and knocking them down, which means that more of them are able to eat enough to survive. Or maybe others tend to die before they can mate because they have a glass jaw. But when we're talking about small fluctuations in bone density, there's going to be some fat looking lizards that keep saying they're just big boned, and skinny lizards with lighter bones.

And out of all those lizards, the skinny lizards with light bones and big flaps seem to be able to jump the furthest. And by the furthest, I mean maybe a couple inches further than their counterparts.

Of course, with all these lizards having sex, you'd think the world would be overrun by lizards. But it isn't, because those lizards have predators eating them. And there's only so much food to go around. Out of a generation of a million lizards, maybe only a hundred thousand live long enough to have sex and pass their genes on to the next generation. And up until recently, the odds of a flap-having lizard surviving were almost identical to the odds of a flapless lizard surviving. But things have changed. Now the flap lizards - and especially the skinny, light boned ones with the biggest flaps - are able to jump far enough that it makes a difference. They can get from one plant to the next just a little faster, so when a bunch of lizards are fighting over a small amount of food, they eat first. When a predator is climbing a tree to catch them, they can jump just a little further than their peers. The odds of lizard survival are greater if they're skinny, have lighter bones and bigger flaps, so more and more lizards will have that trait.

But what about the fatties? Do they all die? Maybe. Or maybe not. Maybe some of the chunky lizards with big bones and thick skin are able to survive the first punch a little better than their light boned counterparts. Maybe the ones with slightly browner skin tone are able to hide on tree bark, and the ones with slightly greener skin tone are able to hide on leaves, and avoid predators altogether. So the green lizards and brown lizards and big boned lizards and skinny light bones lizards with big flaps all tend to live long enough to have kids, while the others tend to die off more often. There are still skinny lizards with heavy bones and fat lizards with flaps and bluer skinned lizards and so on, but with each generation, there are fewer and fewer of them. And over the course of ten thousand more years, this becomes noticable.

And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more.

So now a hundred thousand years have passed, and we've started to see that the bigger the flaps, the lighter the bones, and the skinnier they were, the more they survived. Along the way, maybe they mated with other lizards, too, and some of those may have had desirable traits. Lighter skin might have been desirable for the jumping and gliding, but not so much for survival. But some of these new lizards have really light scales that fold one over the other, the early predecessors of feathers. And that was even lighter than the other lizards. But the same feature wasn't much help to the fat lizards with big heavy bones or the brown lizards or the green lizards, and in fact, those lizards lived longer when they had thicker skin that didn't tear as easily when a predator attacked.

So we start to get speciation. Skinny lizards with light bones and big flaps under their arms and feather like scales lived longer than skinny lizards with heavy bones or heavy lizards with light bones or any other combinations. And over the course of a million years, while they've inherited a substantial number of traits from their great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great grandparents, they bear very little resemblance to them, just like you probably don't look exactly like your grandfather, or your great grandfather, and even less like your great great great great grandfather, and so on.

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Gr00vus said:

Have they stopped shrinking yet?

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Ditka Butkus said:

Gr00vus said:

Have they stopped shrinking yet?

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.I think the humming bird was the previous Triceratops

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Ditka Butkus said:

Gr00vus said:

Have they stopped shrinking yet?

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.I think the humming bird was the previous Triceratops

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Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

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butcher boy said:

How will the Creation Museum portray this latest discovery?

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butcher boy said:

How will the Creation Museum portray this latest discovery?

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Parrothead said:

that explains my pecker

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EYLive said:

So is this the "fact" that scientist are going with until new truths are discovered?

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Leroy Hoard said:

Parrothead said:

that explains my pecker

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It takes a lot of balls to admit that.

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dickey moe said:

bostonfred said:

Same thing that happened with the evolution of wings. Yes, things happened over a long period of time. Yes, small advantages select themselves over time. But why woulda smaller skeletal structure or a tiny flap of skin be advantageous enough to select itself into the species? The obvious answer seems to be that it wouldn't. And the obvious answer is correct.

As a predecessor to a wing or some ability to glide, a tiny flap of skin would be virtually worthless on its own. There is absolutely no reason for the species to select it. Of course, the species doesn't select the trait. It's not like there's some tribal council that says, here here, point of order, the next order of business is that we need to figure out what we want to do with this flap. I say keep it! All those in favor say aye. Instead, what happens is that, one day, a lizard has a weird flap. The other lizards don't pick on him for it because they probably don't notice it. And neither does he. But the good news for him - and for millions of future birdwatchers - is that, like most lizards, he has sex whenever possible, and some - but not all - of their baby lizards have a tiny weird flap just like daddy did.

Now for the sad part of the story: Some of those lizards die. The lizards that die do absolutely nothing to pass on their genetic material. But the ones that live continue to have sex, and some of their offspring also have the weird flap. Not a bigger flap, just the same tiny, meaningless, doesn't-help-in-any-meaningful-way flap in their armpit or between their fingers or whatever. And slowly but surely, some of the flap-havers mate with flapless lizards and their children have a mix of flap and no flap. A hundred years later, in an area with tens of thousands of these little lizards, a few hundred of the great great great great great great great grandchildren of the original flap lizard have flaps. And they've done nothing at all to help those lizards survive. These distant cousins were fortunate enough to survive because they were lizards, not because they had flaps.

But in just a hundred years, a mutation has spread throughout the population. Not to everyone, just to a small group of the lizards. The first lizard that had flaps had sex with lizards that didn't have flaps and after a few generations, some of their kids and grandkids had flaps, and so on. No evolutionary advantage required.

So over a few generations, the Flap family has grown. Now expand that from a hundred years to a thousand years, and some kids have bigger flaps, while others have smaller flaps. Still very small flaps, and hardly meaningful, but there are many lizards with tiny flaps in their armpit, and there's nothing killing them off any faster than their peers so they keep on procreating.

But this is clearly not the only lizard family in the world. There are lots of other lizards. And one of those other lizards gets a weird mutation: a bump on his left shoulder. And the lizard with the bump on his shoulder also has kids, and grandkids, and so on. And some of them have bumps. Some of their bumps are over their left shoulder, some are on the neck, some are bigger, some are smaller. And many generations later, in the whole population of lizards, the Bump family tree is about the same size as the Flap family tree. But you've probably never heard of the Bump-kin, because, like most mutations, they didn't really add any value to the family tree. The same goes for the lizards that had a weird brown blotch on their foot, or the ones with the sligthly bluer skin tone, or the ones with the yellower looking eyeballs. Sometimes lizard kids look weird, but they have sex, and their family tree looks a little weirder because of it.

Similarly, you may notice that your second cousins look more like your great aunts and uncles than your grandparents. Or maybe they look like you, because you both kind of resemble your great grandparents. We've come to expect that tall parents have tall kids and redheads have redheaded kids and people with big noses have kids with big noses, although we alos know that not every trait gets passed down, and some traits skip a generation, or stay on the female side of the family, and so on. The same was true with the lizards. And just like redheads haven't been selected in, neither have they been selected out at this point, so redheads and blondes coexist. And even if there were any kind of evolutionary pressure - for example, if gentlemen really did prefer blondes - the invention of hair dye makes it far less likely that future generations of human will be all blonde, or all brunette, or all redheaded.

So getting back to the flap family - they really didn't make any particular progress, but it didn't fall behind, either. A thousand years have gone by, and there are a lot of lizards with little flaps under their arms, and those lizards aren't jumping much further than their flapless counterparts at all. Over time, the mutation - flaps - is just part of what they look like. And, like any other trait, some of their flaps are bigger, some are smaller. And some of the brown spotted foot lizards have big brown spots and some have little brown spots. And some of the slightly bluer lizards are extra blue while others are greener. All these families are alive and kicking after a thousand years.

Ten thousand years, though, is a long time, and a lot of lizards have had a lot of sex during this time. And during this time, everyone has forgotten the father of the flap family. But by now, the variation in the size of the flaps is noticable. Some are just a millimeter, while others are closer to a centimeter. If you put them side by side, you'd be able to clearly see a difference. And you'd still have a large number of lizards with no flaps whatsoever, because, at this point, there still isn't an evolutionary advantage to having flaps. But the percentage of flaps versus no flaps would still be growing, because the flap family keeps having sex with the flapless, and there's all kinds of intermingling with cousins going on, and who can blame them. They're hot blooded animals.

All of this might be happening over the course of thousands of years, before the first lizards have flaps big enough to meaningfully change their ability to jump. And even then, it's not like those jumping lizards win a prize. At this point, the jumping lizards might be the cool kids in school, but still, the "species" hasn't selected any kind of trait. It's just that some lizards are able to jump further than others.

Meanwhile, just like the flaps and the brown spots and the blue skins, other families of lizards have had heavier and lighter bones. Again, there's nothing specific about light boned lizards that makes them live longer, although this trait has a little more to do with which lizards live and which die. Maybe some of them can climb up a skinny little branch to get to a leaf without the branch bending over and knocking them down, which means that more of them are able to eat enough to survive. Or maybe others tend to die before they can mate because they have a glass jaw. But when we're talking about small fluctuations in bone density, there's going to be some fat looking lizards that keep saying they're just big boned, and skinny lizards with lighter bones.

And out of all those lizards, the skinny lizards with light bones and big flaps seem to be able to jump the furthest. And by the furthest, I mean maybe a couple inches further than their counterparts.

Of course, with all these lizards having sex, you'd think the world would be overrun by lizards. But it isn't, because those lizards have predators eating them. And there's only so much food to go around. Out of a generation of a million lizards, maybe only a hundred thousand live long enough to have sex and pass their genes on to the next generation. And up until recently, the odds of a flap-having lizard surviving were almost identical to the odds of a flapless lizard surviving. But things have changed. Now the flap lizards - and especially the skinny, light boned ones with the biggest flaps - are able to jump far enough that it makes a difference. They can get from one plant to the next just a little faster, so when a bunch of lizards are fighting over a small amount of food, they eat first. When a predator is climbing a tree to catch them, they can jump just a little further than their peers. The odds of lizard survival are greater if they're skinny, have lighter bones and bigger flaps, so more and more lizards will have that trait.

But what about the fatties? Do they all die? Maybe. Or maybe not. Maybe some of the chunky lizards with big bones and thick skin are able to survive the first punch a little better than their light boned counterparts. Maybe the ones with slightly browner skin tone are able to hide on tree bark, and the ones with slightly greener skin tone are able to hide on leaves, and avoid predators altogether. So the green lizards and brown lizards and big boned lizards and skinny light bones lizards with big flaps all tend to live long enough to have kids, while the others tend to die off more often. There are still skinny lizards with heavy bones and fat lizards with flaps and bluer skinned lizards and so on, but with each generation, there are fewer and fewer of them. And over the course of ten thousand more years, this becomes noticable.

And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more. And ten thousand more.

So now a hundred thousand years have passed, and we've started to see that the bigger the flaps, the lighter the bones, and the skinnier they were, the more they survived. Along the way, maybe they mated with other lizards, too, and some of those may have had desirable traits. Lighter skin might have been desirable for the jumping and gliding, but not so much for survival. But some of these new lizards have really light scales that fold one over the other, the early predecessors of feathers. And that was even lighter than the other lizards. But the same feature wasn't much help to the fat lizards with big heavy bones or the brown lizards or the green lizards, and in fact, those lizards lived longer when they had thicker skin that didn't tear as easily when a predator attacked.

So we start to get speciation. Skinny lizards with light bones and big flaps under their arms and feather like scales lived longer than skinny lizards with heavy bones or heavy lizards with light bones or any other combinations. And over the course of a million years, while they've inherited a substantial number of traits from their great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great great grandparents, they bear very little resemblance to them, just like you probably don't look exactly like your grandfather, or your great grandfather, and even less like your great great great great grandfather, and so on.

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Where in the hell did you find time to write this?

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Gr00vus said:

Have they stopped shrinking yet?

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matuski said:

lod01 said:

Maybe we evolved from birds and my great grandfather x2,500,000 was a T-Rex.

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You seem to really know your stuff here.

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Dan Gladden said:

Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

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It's nice to see someone so proud of their ignorance.

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Officer Pete Malloy said:

Dan Gladden said:

Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

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It's nice to see someone so proud of their ignorance.

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If Americans came from England why are there still English people?

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lod01 said:

Officer Pete Malloy said:

Dan Gladden said:

Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

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It's nice to see someone so proud of their ignorance.

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If Americans came from England why are there still English people?

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In a few million years it appears they won't be. They'll be birds or dinosaurs or something new.

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B-Deep said:

There's a shrinking dinosaur in my underpants

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Bob Sacamano said:

B-Deep said:

There's a shrinking dinosaur in my underpants

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Do you think Ichiro bobblehead evolved? Maybe that's why you can't hit it.

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B-Deep said:

Bob Sacamano said:

B-Deep said:

There's a shrinking dinosaur in my underpants

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Do you think Ichiro bobblehead evolved? Maybe that's why you can't hit it.

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he evolved some sort of sixth ding dong and spice drop avoidance sense

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lod01 said:

Officer Pete Malloy said:

Dan Gladden said:

Ditka Butkus said:

Apparently the lizards, snakes, alligators etc. didn't get the ...we are changing into birds memo.

Click to expand...

It's nice to see someone so proud of their ignorance.

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If Americans came from England why are there still English people?

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In a few million years it appears they won't be. They'll be birds or dinosaurs or something new.

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jamny said:

I was just coming in to post exactly what bostonfred said.

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Mr. Cross said:

The dinousaurs died in the Great Flood. They could not go from a giant to a small bird in 6000 years. God created birds.

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