Mouse to elephant? Just wait 24 million generations

Jan 30, 2012
Large evolutionary changes in body size take a very long time. A mouse-to-elephant size change would take at least 24 million generations based on the maximum speed of evolution in the fossil record, according to the work of Alistair Evans and co-authors. Becoming smaller can happen much faster than becoming bigger: the evolution of pygmy elephants took 10 times fewer generations than the equivalent sheep-to-elephant size change. Image: Alistair Evans, David Jones and IMPPS

Scientists have for the first time measured how fast large-scale evolution can occur in mammals, showing it takes 24 million generations for a mouse-sized animal to evolve to the size of an elephant.

Research published today in the (PNAS) describes increases and decreases in mammal size following the extinction of the dinosaurs 65 million years ago.

The research also shows it took about 10 million generations for a cat-sized terrestrial mammals to evolve into the size of an elephant. Sea mammals, such as whales took about half the number of generations to hit their maximum.

Led by Dr Alistair Evans of Monash University's School of a team of 20 biologists and palaeontologists discovered that rates of size decrease are much faster than growth rates. It takes only 100,000 generations for very large decreases, leading to , to occur.

Dr Evans, an and Australian Research Fellow, said the study was unique because most previous work had focused on microevolution, the small changes that occur within a species.

"Instead we concentrated on large-scale changes in body size. We can now show that it took at least 24 million generations to make the proverbial mouse-to-elephant size change – a massive change, but also a very long time," Dr Evans said.

"A less dramatic change, such as rabbit-sized to elephant-sized, takes 10 million generations."

The paper looked at 28 different groups of , including , primates and whales, from various continents and ocean basins over the past 70 million years. Size change was tracked in generations rather than years to allow meaningful comparison between species with differing life spans.

Transformations can happen much faster in animals that live in the water. An increase from rabbit-sized to elephant-sized would take at least five million generations, but the equivalent change in whales takes half as many generations. Becoming smaller is also easier: dwarfing in elephants occurred 10 times faster than the equivalent increase to evolve large elephants. Image: Alistair Evans and David Jones

Dr Erich Fitzgerald, Senior Curator of Vertebrate Palaeontology at Museum Victoria and a co-author, said changes in whale size occurred at twice the rate of land mammals.

"This is probably because it's easier to be big in the water – it helps support your weight," Dr Fitzgerald said.

Dr Evans said he was surprised to find that decreases in body size occurred more than ten times faster than the increases.

"The huge difference in rates for getting smaller and getting bigger is really astounding – we certainly never expected it could happen so fast!" Dr Evans said.

Many miniature animals, such as the pygmy mammoth, dwarf hippo and 'hobbit' hominids lived on islands, helping to explain the size reduction.

"When you do get smaller, you need less food and can reproduce faster, which are real advantages on small islands," Dr Evans said.

The research furthers understanding of conditions that allow certain mammals to thrive and grow bigger and circumstances that slow the pace of increase and potentially contribute to extinction.

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tigger
4.3 / 5 (24) Jan 30, 2012
"...we certainly never expected it could happen so fast!"

Indeed. And I wager that many naysayers of evolution are somewhat at odds with the use of the word "fast" here... since they are often expecting evidence in the form of a monkey giving birth to a human being.
Parsec
3.7 / 5 (19) Jan 30, 2012
Sadly, most evolution deniers would doubt the evidence even in that case. Remember, evidence is for scientists, blind faith is for religion. Its really hard to reconcile the two.

Notice here I am not saying its impossible. There are a lot of scientists who are also quite strong in their spirituality, and a lot of quite spiritual people who embrace science and the principles it holds to.

Unfortunately, it requires an open mind AND an open heart to realize that there really isn't a conflict. And that's kinda rare.
antialias_physorg
3.8 / 5 (21) Jan 30, 2012
Unfortunately, it requires an open mind AND an open heart to realize that there really isn't a conflict.

Unfortunately there is a conflict. NOMA just doesn't work. The scientific method and belief in a predetermined outcome (i.e. the existence of some supernatural power) are mutually exclusive.

As soon as there si something that has an effect it is within the realm of science. Spiritual people will most certainly claim that their spirituality has an effect (if nothing else then on themselves).

Anyone who claims to be a 'spiritual scientist' is most certainly not involved in any of the hard sciences (maybe theology or philosophy or psycholog)
Silverhill
4.4 / 5 (14) Jan 30, 2012
Note to Henrik and kevinrts: Just stay away, OK? (Unless you truly have somthing to contribute about the *science* here.)
Telekinetic
2.4 / 5 (24) Jan 30, 2012
"Anyone who claims to be a 'spiritual scientist' is most certainly not involved in any of the hard sciences (maybe theology or philosophy or psycholog)" -antialias

"Planck made many contributions to physics, but is best known for quantum theory, which has revolutionized our understanding of the atomic and sub-atomic worlds. In his 1937 lecture "Religion and Naturwissenschaft," Planck expressed the view that God is everywhere present, and held that "the holiness of the unintelligible Godhead is conveyed by the holiness of symbols." Atheists, he thought, attach too much importance to what are merely symbols. Planck was a churchwarden from 1920 until his death, and believed in an almighty, all-knowing, beneficent God (though not necessarily a personal one). Both science and religion wage a "tireless battle against skepticism and dogmatism, against unbelief and superstition" with the goal "toward God!"
There are dozens of other well-known 'spiritual scientists.'
Deesky
4.4 / 5 (14) Jan 30, 2012
Tele, your random, out of context quotes in no way negate AP's point, which is a good one.
Telekinetic
1.4 / 5 (18) Jan 30, 2012
Deesky:
How is antialias' point a good one if it's false?
Deesky
4.8 / 5 (23) Jan 30, 2012
Deesky:
How is antialias' point a good one if it's false?

It's a good one because it ISN'T false. The word 'conflict' here doesn't mean physical conflict or a war of words. It's a fundamental conflict in critical thinking and the application of the scientific method to all things, not just narrow fields of specific interest. In the same way, there is no 'Christian' science - there is only science.
Telekinetic
1.9 / 5 (16) Jan 30, 2012
Far be it from me to put words in Planck's mouth, but I doubt that he'd make the distinction you're making.
MorituriMax
2.5 / 5 (11) Jan 30, 2012
tigger,
"...we certainly never expected it could happen so fast!"

Indeed. And I wager that many naysayers of evolution are somewhat at odds with the use of the word "fast" here... since they are often expecting evidence in the form of a monkey giving birth to a human being.
tigger, monkeys didn't give birth to humans, the common ancestor of monkeys AND humans gave birth to humans.
jsa09
4.2 / 5 (5) Jan 30, 2012
Size change was tracked in generations rather than years to allow meaningful comparison between species with differing life spans.


Except that I have a problem with generations which is almost the same problem as using years.

A mouse sized animal may have 1 year generation perhaps, depending on the animal. An elephant sized animal may have a lifespan 10 - 20 years generation.

So changing from mouse size to elephant size in 24 mill gens. creates a problem in guessing the length of a generation.

What is Human generation BTW is it 15 years? or more? or less?

I would presume the generation gets longer as the animal gets larger but it is not a smooth curve and generation may change faster or slower than size change depending on evolutionary forces in specific circumstance.
MorituriMax
2.5 / 5 (13) Jan 30, 2012
Telekinetic, why would any scientist who honestly and truly believes in "God" ever become a scientist?

If they do believe in "God" there is no point in trying to understand what makes the Universe go round. You just accept that whatever happens, "God" did it. You just answer every question with God Did It, and It's Not Ours To Question Why.

disclaimer: "God" implies supernatural man in the sky, somewhere, personally involved in managing all the Universes.
Telekinetic
1.5 / 5 (15) Jan 30, 2012
"I would presume the generation gets longer as the animal gets larger but it is not a smooth curve and generation may change faster or slower than size change depending on evolutionary forces in specific circumstance."-Jsa09
Turtles and parrots are long-lived while very tall people have shortened life spans.
Deathclock
2.3 / 5 (6) Jan 30, 2012
"I would presume the generation gets longer as the animal gets larger but it is not a smooth curve and generation may change faster or slower than size change depending on evolutionary forces in specific circumstance."-Jsa09
Turtles and parrots are long-lived while very tall people have shortened life spans.


The correlation between body size and life span is tenuous at best... it exists but there are many exceptions.
Telekinetic
2.2 / 5 (17) Jan 30, 2012
"Telekinetic, why would any scientist who honestly and truly believes in "God" ever become a scientist?"- MorituriMax
What if someone was an atheist before studying science and then began to believe in God even as a scientist. It's absurd to think that people think or believe in absolute terms, precluding them from doing something that doesn't fit the stereotype. I'm sure there are prostitutes and porn actors who believe in God, why is that hard to imagine? I wonder how someone can be a Republican and call themselves a human being, but there they are, or at least they look like people. There is no black and white to any issue, even science has its grey areas.
dogbert
2.8 / 5 (16) Jan 30, 2012
...why would any scientist who honestly and truly believes in "God" ever become a scientist?


Scientists seek to understand the physical world. Why would the existence of God suppress that desire? (It doesn't, of course.)
Deesky
4.1 / 5 (9) Jan 30, 2012
Far be it from me to put words in Planck's mouth, but I doubt that he'd make the distinction you're making.

You really want to argue facts by quote mining? And from something that was said some hundred years ago? For pete's sake, Planck was born in the 1850s, a time where strong religious beliefs were very common and the wealth of current contemporary knowledge was unimaginable.

But, putting that aside. I'll see your quote and raise you one:

"Science enhances the moral values of life, because it furthers a love of truth and reverence love of truth displaying itself in the constant endeavor to arrive at more exact knowledge of the world of mind and matter around us"

"Religion belongs to that realm that is inviolable before the laws of causation and therefore closed to science" - Another words, a philosophical position at best.
Sinister1811
1.7 / 5 (11) Jan 30, 2012
That is awesome. So if you were to fast forward to the future, you would be able to see different megafauna..?
Deesky
4.6 / 5 (9) Jan 30, 2012
What if someone was an atheist before studying science and then began to believe in God even as a scientist. It's absurd to think that people think or believe in absolute terms, precluding them from doing something that doesn't fit the stereotype.

It's not a question of 'stereotypes'. It's not about pointing to a single individual or more and saying: look, there's your exception.

The original bone of contention in this discussion was about there being tension or conflict between the notion of scientific critical thinking in all things vs research done filtered by the prism of religious baggage. In the end, the results may well be perfectly valid, but to suggest that there isn't a conflict in thought and approach is naive.
Infinite Fractal Consciousness
3.5 / 5 (8) Jan 30, 2012
To some of us, "God" = "Everything." Not all of those who are spiritual are anti-science. Those guys are idiots.
Deesky
4.5 / 5 (8) Jan 30, 2012
That is awesome. So if you were to fast forward to the future, you would be able to see different megafauna..?

Depends on how far in the future you go. While humans are still the dominant species, it's unlikely you will see much megafauna, let alone different forms. Millions of years after the demise of humans, I'd say you'd have a much better chance of seeing different megafauna.

Though don't fast forward too much, as the Earth will become unlivable for most animals (700 - 1000 million years) due to solar heating.
Telekinetic
1.6 / 5 (13) Jan 30, 2012
" For pete's sake, Planck was born in the 1850s, a time where strong religious beliefs were very common and the wealth of current contemporary knowledge was unimaginable."-Deesky

Planck lived until 1947, so he was exposed to many modern thoughts and concepts that are as modern as any today. Don't forget his quantum theory must've raised a few eyebrows in his day when he presented them to the scientific community. I personally think it's paradoxical that men of his mental caliber and rigorous training could "believe" in a concept as nebulous as God. But that's what life continually presents to us, having our assumptions thrown up in our faces, and coming to grips with these incongruities.
Sinister1811
2.2 / 5 (13) Jan 30, 2012
Millions of years after the demise of humans, I'd say you'd have a much better chance of seeing different megafauna.

Though don't fast forward too much, as the Earth will become unlivable for most animals (700 - 1000 million years) due to solar heating.


Very true. I could not agree more with that.
Telekinetic
2.1 / 5 (14) Jan 30, 2012
"The original bone of contention in this discussion was about there being tension or conflict between the notion of scientific critical thinking in all things vs research done filtered by the prism of religious baggage. In the end, the results may well be perfectly valid, but to suggest that there isn't a conflict in thought and approach is naive."-Deesky
In terms of Planck's work, there was no interference,
coloration, or adulteration from his beliefs. It is prejudicial on your part to expect that it would be. His work is considered the gold standard in scientific circles to this day.
Deesky
5 / 5 (5) Jan 30, 2012
I personally think it's paradoxical that men of his mental caliber and rigorous training could "believe" in a concept as nebulous as God.

His 'belief' was a philosophical one in the sense that he believed an agent set off the big bang but which subsequently lead to the laws of physics and chemistry through natural processes (ie, no further involvement by the instigating agent).

That is a purely philosophical notion as no one can know what happened before or at the BB, or what caused it, as we have no information about the event itself (just some time afterwards).

So Planck brings no religious, dogmatic baggage to his prosecution of science and therefore no conflict.
Deesky
5 / 5 (3) Jan 30, 2012
In terms of Planck's work, there was no interference,
coloration, or adulteration from his beliefs. It is prejudicial on your part to expect that it would be.

Straw man. Where did I claim that his work was tainted in any way? In fact, I made clear quite the opposite.
Deesky
5 / 5 (10) Jan 30, 2012
Grrr. Who the hell came up with this new paged comment section? It just impedes navigation!

You go to refresh the page and it takes you back to page 1! You change the post order to 'oldest first', do a page reload and it takes you back to 'newest first' and back to page one!!!

It even makes searching difficult as you have to keep loading pages until you find what you're after! What the hell is the point of this???
Telekinetic
2.2 / 5 (11) Jan 30, 2012
Still no conflict from his beliefs because his mathematics, which allowed Einstein to formulate his equations, bore no mention of God or religion at all. If the body of work is accepted as fact by mainstream science, where could there be conflict? If you ostracize people because of religious belief, and think their work is inferior or deny them work because of their belief, then you're no better than those who espouse racial and religious hatred.
Henrik
Jan 30, 2012
This comment has been removed by a moderator.
davhaywood
2.7 / 5 (3) Jan 30, 2012
There is absolutely no conflict between spirituality/belief and science. The interests and pursuits lie in completely different realms -- metaphysics and empiricism. Problems do arise, however, when one attempts to reconcile irreconcilable differences between the two. Spirituality is an element of human experience which defies any attempt at proving it empirically and the physical world defies any attempt to bring religion or belief to bear on it. Though, I will say that I personally think that science has gleaned more information about spirituality than the inverse. In any case, this can either be a strength, or a weakness of spirituality depending on one's point of view.
Deesky
4.3 / 5 (6) Jan 30, 2012
Still no conflict from his beliefs because his mathematics, which allowed Einstein to formulate his equations, bore no mention of God or religion at all. If the body of work is accepted as fact by mainstream science, where could there be conflict? If you ostracize people because of religious belief, and think their work is inferior or deny them work because of their belief, then you're no better than those who espouse racial and religious hatred.

Boy, you really do have poor reading comprehension abilities. Go on, make up some more false conclusions from unstated arguments - I'm out.
davhaywood
4.6 / 5 (9) Jan 30, 2012
Henrik, you display once again your ignorance of evolution. Intermediates are their own fully-formed beings. In any case, the fossil record isn't even the hardest piece of evidence for evolution, not that you care.
kochevnik
2.8 / 5 (4) Jan 30, 2012
To some of us, "God" = "Everything." Not all of those who are spiritual are anti-science. Those guys are idiots.
Sadly the Henriks of the world often confuse "everything" with "nothing", which begets much of humanity's woes.
Telekinetic
1.5 / 5 (8) Jan 30, 2012
"His 'belief' was a philosophical one in the sense that he believed an agent set off the big bang but which subsequently lead to the laws of physics and chemistry through natural processes (ie, no further involvement by the instigating agent)."- Deesky
Planck believed in God, not as a mere philosophy or whose influence ended after the Big Bang. That's a facile description to make him more palatable to you and to conveniently tie up the loose ends of your argument. He wasn't completely rigid, and had differences with the church regarding unquestioning belief. There is plenty of room in this world for differing beliefs, so long as one's own doesn't persecute another's.

Silverhill
4.8 / 5 (5) Jan 31, 2012
Henrik:
There is no evidence that their fancy story telling ever occured in real life.
Pot, meet kettle!
Deesky
5 / 5 (2) Jan 31, 2012
Planck believed in God, not as a mere philosophy or whose influence ended after the Big Bang

I guess you must have missed this quote of his, which invalidates your comment:

"Religion belongs to that realm that is inviolable BEFORE the laws of causation and therefore closed to science".

Pure philosophy (well, about the religion part).
bewertow
4.3 / 5 (6) Jan 31, 2012
not those fairy-tale intermediates.


LOL! Wow that's really ironic considering you believe in a sky fairy who is his own father.
Tausch
1 / 5 (3) Jan 31, 2012
...a team of 20 biologists and palaeontologists discovered that rates of size decrease are much faster than growth rates...


See?*
*(What happens when size doens't matter!)**

**We single cells are by thousands of magnitudes the most abundant form of life of any period of life on earth.

Yeah, we're fast too. Size doesn't matter. If survival were a measure of dominance and/or intelligence we at least give you multicellulars food for thought - literally too. :)
cyberCMDR
5 / 5 (3) Jan 31, 2012
"Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." Attributed to Seneca.
The conflict between religion and science is that science engages critical thinking. Some can compartmentalize and avoid critical thinking regarding their beliefs, but science time and again disproves many assertions by the religious.
To pick on a religion besides Christianity, Mohammed said in the Koran that if a fly lands in your drink, you should dunk it in fully because the fly carries diseases on one wing but the other wing carries the cure. An easy proclamation to test and disprove, just as the Young Earth assertions are easy to disprove.
Cynical1
1.8 / 5 (5) Jan 31, 2012
Doesn't it all really boil down to how - or what you define as - a god?
Cynical1
1.8 / 5 (5) Jan 31, 2012
how - or what you define as - a god?
Sorry. Hyphenated incorrectly... (Don't they have an inhaler for that?)

how - or what - you define as a god.
Makes all the difference...:-)
Anda
3.7 / 5 (3) Jan 31, 2012
Unfortunately, it requires an open mind AND an open heart to realize that there really isn't a conflict.

Unfortunately there is a conflict. NOMA just doesn't work. The scientific method and belief in a predetermined outcome (i.e. the existence of some supernatural power) are mutually exclusive.

As soon as there si something that has an effect it is within the realm of science. Spiritual people will most certainly claim that their spirituality has an effect (if nothing else then on themselves).

Anyone who claims to be a 'spiritual scientist' is most certainly not involved in any of the hard sciences (maybe theology or philosophy or psycholog)


I don't believe in gods, but Einstein did. That's one of the reasons he couldn't accept quantum behaviour (god doesn't play dice). But I don't think he was into theology, philosophy or psychology...
As many other scientists...

Blakut
4 / 5 (4) Jan 31, 2012
Einstein's quote about God was a metaphor, he was denying the indeterministic nature of the world. I am an atheist and i exclaim "Oh my God!" or "God only knows" sometimes, just because i grew up in a culture where these phrases are very common.
Henrik
1.6 / 5 (14) Jan 31, 2012
Henrik, you display once again your ignorance of evolution.


Let me then offer you a quote coming from someone with this alledged knowledge:

"All paleontologists know that the fossil record contains precious little in the way of intermediate forms; transitions between major groups are characteristically abrupt." [evolutionist Stephen Jay Gould]

"If I knew of any, fossil or living, I would have certainly included them. I will lay it on the line, there is not one such fossil for which one could make a watertight argument."
[Colin Patterson, senior paleontologist at the British Museum of Natural History]
roboferret
4.5 / 5 (8) Jan 31, 2012
Creationists love quoting out of context.
Gould advocated punctuated evolution, which makes sense in the light of evolution being a dynamical system, self-organised criticality producing rapid change between relatively stable states.
(Creationists hate SOC, it mathematically demonstrates how complexity can arise from simple non-linear interactions).

For what Patterson actually said, in context, see this link.
http://www.talkor...son.html
Old Badger
2.8 / 5 (9) Jan 31, 2012
If something as relatively simple as body size requires timescales in the hundreds of millions of years to evolve, this reignites the debate about the span of time available for evolution. After all, once the first mammal has evolved, all the difficult part has been done - all the biochemistry, all the bio-engineering. If it takes 100 million years just to make it a little larger, then the 1 billion years between the appearance of the first multicelled organism and mammals appears woefully inadequate to accommodate any evolutionary process yet identified. Why don't we all admit that we still don't have the first clue about what really happened? The mystery is as profound as it was in Darwin's day. Probably a few centuries more research is required until we gain some deeper understanding. In the interim the debates about evolution and creationism, each based on almost total ignorance, are truly risible!
Deathclock
Jan 31, 2012
This comment has been removed by a moderator.
Deathclock
Jan 31, 2012
This comment has been removed by a moderator.
roboferret
4.4 / 5 (7) Jan 31, 2012
*Facepalm*
Systems evolved in parallel. They didn't evolve one organ at a time.
Deathclock
Jan 31, 2012
This comment has been removed by a moderator.
Henrik
Jan 31, 2012
This comment has been removed by a moderator.
Henrik
Jan 31, 2012
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