Evolution of Mammals Re-evaluated

AaxelB writes "A study described in the New York Times rethinks mammalian evolution. Specifically, that the mass extinction of the dinosaurs had relatively little impact on mammals and that the steps in mammals' evolution happened well before and long after the dinosaurs' death."

What About the Other Dinosaurs?

[by Anonymous Coward]

Most paleontologists now think that birds descended from dinosaurs. So in a sense, even dinosaurs in one form escaped the calamity.

Don't forget varanus komodoensis [wikipedia.org] ... and Strom Thurman [wikipedia.org], he died out only four years ago and was the most prominent organism to escape the icy grasp of natural selection!

Re:What About the Other Dinosaurs?

[by Anonymous Coward]

"...Dinosaurs were created on day 6 of the creation week approximately 6,000 years ago, along with other land animals, and therefore co-existed with humans."

"...Dinosaurs lived in harmony with other animals, (probably including in the Garden of Eden) eating only plants;" and "pairs of each dinosaur kind were taken onto Noah's Ark during the Great Flood and were preserved from drowning."

"Dinosaur bones originated during the mass killing of the Flood;" and "some descendants of those dinosaurs taken aboard the Ark still roam the earth today."

And you can look that up! [conservapedia.com]

Re:What About the Other Dinosaurs?

[Monokeros (200892)]

Easy. Elephants, hippos, alligators, lions, polar bears, and kitty cats were the food for the dinosaurs. The dinosaurs made their way through the dragons, unicorns, hobbits and fairies by the time the flood ended and the rest were spared. They're living on a ranch in Montana now.

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[toadlife (301863)]

One small correction that doesn't refute your point. It *rained* for 40 days, but after the rain stopped, the Ark was adrift for several months before finding land again.

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[truckaxle (883149)]

The biblical record states that the animals come to Noah.

The Noachian flood is falsifiable on so many different levels - it really only takes a few minutes of unbiased thinking.

Just how did these baby polar bears, kola bears, blind cave fish and blind mole rats make the oceanic journey and arrive in the Middle East.

Or better yet on the other end. Why is there *strong* geographic patterns of species distribution. For example, how did the marsupials almost exclusively arrive in Australia?). Biogeography, is

Re:What About the Other Dinosaurs?

[Tatarize (682683)]

My question is what color was the sky prior to Noah's flood?

Oddly enough, in the story, after God drowns everything for being completely evil. Man, woman, child, infant, fetus... all dead. God feels really really bad about it. Apparently he didn't think it through or know what was going to happen so in Genesis 9:9-13 he makes rainbows exist as a way to say, "I'm really sorry and will never do it again." -- However, rainbows are produced by a fairly trivial byproduct of the diffusion of white light through a medium. This is roughly why we have a blue sky. The light from the sun is diffused and the blue light is diffused more than the other colors. However, if this diffusion didn't exist before God screwed up by drowning everybody and everything (seems like a better solution than later sacrificing Himself to Himself to pay Himself for the debt mankind owes to Him and worse than just not keeping a grudge against people who didn't do anything wrong but somehow get the blame for some other mythological couple doing something wrong without the facilities to tell right from wrong), what color was the sky?

Re:What About the Other Dinosaurs?

[Peter La Casse (3992)]

Just how did these baby polar bears, kola bears, blind cave fish and blind mole rats make the oceanic journey and arrive in the Middle East.

Magic.

Oh, you don't believe in magic? Then you don't need any more reason to disbelieve that a magical being caused a worldwide flood, but you'll need harder questions than those to convince people who do believe in magic that it doesn't really exist.

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[Citizen of Earth (569446)]

Just how did these baby polar bears, kola bears, blind cave fish and blind mole rats make the oceanic journey and arrive in the Middle East.

And once there, how did Noah have room for over 1.25-million different species of animals on his boat? Did Noah save the plants? How did they get there?

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[steelfood (895457)]

The dieties in the old testament are not the all-powerful, all-knowing Diety in the new testament. The god in the old (who admits he is actually one among many in the first commandment through forbidding of the worship of the others) might be significantly more powerful than a mere human, and immortal to boot, but not nearly as "perfect" as the God in the new. Attempts to reconcile the two would only result in numerous logical inconsistencies. Why, for example, would an omniscient diety need to test believe

God is Luv....

[truckaxle (883149)]

Most people, you being one, criticize the Bible, having never read it, let alone carefully studied it with an open mind. If you had, you would read passages like:

Sure like:

Deuteronomy
"As you approach a town to attack it, first offer its people terms for peace. If they accept your terms and open the gates to you, then all the people inside will serve you in forced labor. But if they refuse to make peace and prepare to fight, you must attack the town. When the LORD your God hands it over to you, kill every

Alternate theory

[Average_Joe_Sixpack (534373)]

Most sensible explanation [youtube.com]

Magic man done it theory

[Bowling Moses (591924)]

A magic man done it! [youtube.com] With "forcey forces" of coursey.

Re:Alternate theory

[franksands (938435)]

Sorry for the comment abuse, but I just had to post this comment from youtube:

evilc27 (2 hours ago)
The fact that we are born babies and evolve into people is evidence enough to dispel the myth of evolution. If we were born monkeys, then there would be billions of monkeys in the world as there are billions of people. This does not equate. People have called me stupid for expressing my facts, but I am far from stupid. I took an IQ test at my church school, and I scored 95. You cannot get more than 100% and so I am in the top 5% of the smartest people in the world. chew on that disbelievers.

This just made my day.

Wasn't this common knowledge?

[elhondo (545224)]

I had thought this point was actually a point of disagreement between Gould and Dawkins, with Dawkins pointing out that the cambrian explosion wasn't as sudden as Gould had pointed out. I think this particular point was discussed in Bryson's "A Brief History of Nearly Everything". I didn't think anyone still held this viewpoint about mammalian evolution anymore.

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[AJWM (19027)]

What the hell does the cambrian explosion have to do with mammalian evolution? There's a several hundred million year time span between the two, and that's just to the beginning of the mammal line with the synapsids like dimetrodon. Add another hundred million or two before we get to anything that most people would consider mammalian.

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[victorvodka (597971)]

Dude you said "cambrian" - there was a cambrian explosion too and perhaps that's what you mean. But here we're talking about the Cretaceous, 65 Million years ago instead of 600 Million years ago.

Hrmm...

[grub (11606)]

But can they shoehorn it into the framework of a 6000 year old Earth?

Evolution? I thought Jebus created the dinosaurs!

[Ralph Spoilsport (673134)]

How could it be true otherwise?

Here's an interesting question: how long did it take for creatures to speciate after the Permian extinction? I wonder if there was the same amount of lag-time after that disaster...

RS

Re:Evolution? I thought Jebus created the dinosaur

[rucs_hack (784150)]

I thought it was about six million years, could be wrong though.

The big thing was grass, it hadn't been around for most of the time the dinosours had existed. The domination of grasses after the CT event really helped the spread of species

well, duh.

[Triv (181010)]

I've known about this since Sunday [youtube.com].

Triv

Shamelessly off-topic, but must be done...

[jeevesbond (1066726)]

From Conservapedia [conservapedia.com]:

The Theory of evolution is a materialist explanation of the history of life on earth. Despite being the scientific standard, in the United States, there are a significant number of lay people who do not accept evolution. According to a CBS poll, only 13% of American adults believe humans evolved without divine guidance.

A CBS survey said there's no evolution! If 87% of people say there's no evolution then this article is a sham sir!

Back on-topic, what interests me is:

But the researchers conceded that much more research would be required to explain the delayed rise of present-day mammals.

If it wasn't the dinosaurs stopping the evolution of mammals (i.e. dinosaurs dominating the habitat), then what did? Could it be that the available habitats were just better suited to dinosaurs vs. mammals? That's the first thing that springs to mind (although am no paleontologist). As ever with this sort of thing, the finding raises more questions than it answers!

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[geek (5680)]

Well, I may be corrected on this but I'll say it anyway since it's what I was taught in college. The median world temp around the peek of the dinosaurs was very high, somewhere around 130 to 140 degrees and there was a much larger amount of CO2 in the air. I would have assumed that as this changed mammals were given their chance at the top of the food chain.

I always interpreted mammalian evolution to be parallel with climate change. I suspect however many people would disagree.

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[Harry Coin (691835)]

Nope. It's not satire. It was created by Andrew Schlafly, son of arch-conservative anti-femininst Phillys Schlafly [wikipedia.org], and is used by her Eagle Forum [wikipedia.org].

If the ideas presented on that site induce laughter, it is because neoconservative ideas are completely ridiculous. Really, Mark Twain couldn't produce satire so deep. I honestly hope that the GOP uses that site as their definitive reference. Within two generations, they'll be too stupid to breed.

LIAR

[Doc Ruby (173196)]

Conservapedia is self-parody, but it is produced and maintained by "Conservatives" as a repository of official "Conservative" dogma. Because they think Wikipedia is "liberal", as they clearly state in their About [conservapedia.com] page. Typically Conservative, they're using the Wikipedia software for free, but don't even mutter a minimal thanks to Wikipedia - they just bash it.

Anonymous Conservative Coward is a typical Conservative: trying to have it both ways, all ways, whenever it's convenient. There is no "truth" for today's "Conservatives" (What are they "conserving"? They're wasters, reckless consumers and rampant destroyers.) So whenever they dart out from behind their favorite weasel words to make a clear statement, they're usually a joke, at least because they contradict whatever other statement they made before that was once convenient then.

"Reality has a well-known liberal bias." - Stephen Colbert [thinkprogress.org]

and that's sad...

[CasperIV (1013029)]

Whats worse is that some of those surveyed might not be in Alabama...

Re:Shamelessly off-topic, but must be done...

[Daniel Dvorkin (106857)]

There is obviously no evidence that the mutations which gave rise to speciations were "random" and not in some way directed, naturally or supernaturally, or otherwise forced in some particular direction.

"Obvious" if you ignore pretty much all work in molecular genetics at least since Watson and Crick.

Once we arrive at a better understanding of how DNA works, perhaps it will be possible to form mathematical models to determine whether or not the "random mutation" theory is feasible.

You mean, the way bioinformaticists and statistical geneticists do all the time, right now, and have been for years?

Maybe it's only feasible during intermittant radiation events that decimate populations by causing widespread mutations, leaving a few individuals with improvements, who go on to reproduce and build up populations again. Maybe it's not possible at all.

Do you have any data, at all, that would support either one of these hypotheses? Or are you just cut'n'pasting from some ID site somewhere?

Many mammalian lineages predate the K-T extinction

[saforrest (184929)]

If you read The Ancestor's Tale [amazon.com] by Richard Dawkins, you'll find that recent genetic evidence suggests that many of the distinct branches of modern mammals predate the K-T extinction.

In particular, by the time of the K-T extinction, I believe that the primate lineage had already separated from rodents, as well as the laurasiatheres [wikipedia.org] (all hoofed mammals, lions, tigers, bears, etc.), xenarthrans [slashdot.org] (armadillos, sloths, etc.), and afrotheres [wikipedia.org] (elephants, manatees, anteaters, etc.).

So, while most mammals in the Cretaceous may still have been tiny shrew-like creatures scurrying around in the underbrush, many of the modern lineages had already come into separate existence.

It is also interesting to read, in the book, that our nearest non-primate relatives aside from the tree shrews are rodents. I can sort of see it: give a mouse a little more finger dexterity and it wouldn't not that different from a lemur. It also might explain why rodents are such good laboratory specimens.

Yes, and....

[Conspiracy_Of_Doves (236787)]

Specifically, that the mass extinction of the dinosaurs had relatively little impact on mammals and that the steps in mammals' evolution happened well before and long after the dinosaurs' death.

Do they think that those steps ever could have taken place if the dinosaurs were still around?

Re:From a friend

[Tackhead (54550)]

> a similar analysis for birds, published recently in the journal Biology Letters, revealed that more than 40 avian lineages survived the mass extinctions. Most paleontologists now think that birds descended from dinosaurs. So in a sense, even dinosaurs in one form escaped the calamity.

In other words, chicken tastes like dinosaur!

(In Creationist America and Lysenkoist Russia, dinosaurs taste like chicken!)

Re:From a friend

[Cro Magnon (467622)]

So in a sense, even dinosaurs in one form escaped the calamity. I found it pretty cool.

It's not so "cool" having to clean dinosaur droppings off my car, though.

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[thePig (964303)]

Can it be because there is more selection pressure due to the dinosaurs?
If there is more selection pressure, more the chance of diverging to new species.
And when dinosaurs died out, the mammals had a field day.

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[gardyloo (512791)]

Speaking of misleading titles! I got all excited about your post's title, anticipating a link to some Miss Universe-type website. Instead, all I got was a one-sentence comment.

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[zappepcs (820751)]

Yeah, sure. This one species of mammals is totally different from all the rest of them.

Not to bait flames here, but the evidence for divine creation is pretty damned weak if you take into account all the imperfect humans that had to be involved in bringing us 'his word'... while the evidence for evolution is getting stronger all the time, and this little theory of evolution doesn't mind a few corrections here and there. It's a bit tolerant of the process of discovery.

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[Oligonicella (659917)]

So, you propose that because we are humans, somehow we should ignore the tons (literally) of evolutionary evidence concerning our origins? Nope.

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[ChrisMaple (607946)]

The purpose of having words, sentences, and languages is to express thoughts. Throwing together phrases in defiance of sense defeats this purpose.

I know that cold hard facts should trump what we wish to be true, but for a question as fundamental as the origin of our own existence, maybe it works the other way.

This is just nonsense. For fundamental and crucial things, it is of the highest importance to use the rules of logic that make human understanding possible.

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[Oligonicella (659917)]

Evolution is a theory of science, not a parlor talk theory. There is no faith in evolution, only vast reams of empirical data supporting it.

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[ajs (35943)]

Evolution is a theory of science, not a parlor talk theory. There is no faith in evolution, only vast reams of empirical data supporting it.

That over-states the case rather drastically. First off, there's an awful lot of faith in evolution, and that's actually a point that far too many folks who defend evolution blindly should accept, otherwise they get blindsided with the news that ... shock, some corner of the theory was actually wrong.

There's faith in the idea that what we observe is representative of what happened before recorded history. There's faith that empiricism is generally valid (watch how many people leap to defend empiricism and

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[testpoint (176998)]

I have recently examined the Marzeah Papyrus (7th century B.C.), fragments of the dead sea scrolls, septuagint leviticus , septuagint exodus and Gospel of John fragments all from the 3rd century A.D. Modern, nonparaphrased, versions of the Bible, corresponding to these fragments are accurately translated.

Many of the original writers and earliest translators could write and speak multiple languages. While you might consider them superstitious they weren't illiterate. William Tyndale, a 16th century sc

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[Hognoxious (631665)]

Evolutionary is just a theory, not a law

It's neither - it's an adjective, meaning of, or pertaining to, evolution.

Re:This is Great

[Coryoth (254751)]

Until the next "re-thinking." Will we ever have hard evidence, or just thought experiments?

But we do have hard evidence - indeed it was hard evidence that helped lead to this rethinking. Recently there have been a number of finds of surprisingly large mammals that are much older than had previously been expected. They include a beaver like (pre)-mammal [wikipedia.org] from the Jurassic that was almost half a metre long, discovered in 2004, and two species large carnivorous mammal from the cretaceous [wikipedia.org] (dated to about 130 million years ago - or 65 million years prior to the dinosaur extenction) which were discovered in 2000 and 2005. Such large mammals (relatively speaking) during the time of the dinosaurs draws into question the previous belief that mammals were restricted to small rat/mouse like scavengers at that time. Instead we see evidence of large, active, meat eating mammals. This implies that mammals were rather less marginalised during the dinosaurs "reign" than previously thought, and imples that mammal evolutionary history needs to be rethought accordingly.

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[Coryoth (254751)]

I should add that these fossil discoveries lead to various people taking a more serious look at the presumed facts of mammal evolution and were the catalyst for a "rethink", however there is even more "hard evidence" in the paper cited by the NYT article which was a far more detailed study looking at far more fossil (and apparently molecular) evidence.

Trolly trolly troll troll.

[SatanicPuppy (611928)]

Re-Thinking? Well, hell if you knew it wasn't right, why didn't you say so before?

Jeez.

See, this is why Creationism is right...No rethinking required. Ever.

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[Fordiman (689627)]

"Nobody has EVER made a fossil. NO fossils are being made anywhere today, especially by any slow, gradual process, sometimes imagined by evolutionists."

Two words: Snow Mummies.

"To prevent this, a dead body needs to be put in an environment that prevents all microorganisms from feeding on the remains and oxygen must be excluded."

Hm. Like drowning in tar?

"A sudden disastrous upheaval such as the Biblical flood could certainly account for fossils."

Yes. Because there are no waterborne microorganisms.

Read as "N

Re:"Rethinking"

[Kozar_The_Malignant (738483)]

A. Coward wrote:

Until the next "re-thinking." Will we ever have hard evidence, or just thought experiments?

Actually, the ideas contained in the Nature article are based on new, hard evidence, not a "rethinking" of thought experiments. Or didn't you read the linked NYT article? That's how science works.

Re:Science rethinking.

[flitty (981864)]

Science is often championed as being very sure... especially evolution,

I'm calling you on this rediculous statement. Science is only as sure as they can prove. You'll hardly find a scientist who, under new evidence or studies, will say "nope, the way we used to believe is more correct, and i'll be damned if i take your new evidence into consideration!"
Sounds more like religion to me.

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[RatBastard (949)]

A valid question. That evolution happens is a known fact. That animals adapt over the generations and change to the point that disparate isolated populations can no longer interbreed is a fact. What is constantly being reevaluated is the actual mechanisms that drive this change. Early assumptions are reexamined when they don't hold up to scrutiny. Theories are revised when we discover that things are more complex than we thought. Natural selection (higher survival potential) does not explain creatures

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[Coryoth (254751)]

Does it raise questions in no one else's mind when it is quite consistently being "rethought?" It seems it should not be dogmatically asserted as it is now, nor should a "rethinking" be taken in stride as if it's entirely normal behavior for science. And yes, I know it's not a scientific fact, it is a scientific theory, as most scientific thoughts are - but most school kids don't know much of the difference between "fact" and "scientific theory." It's simply taught...Maybe informative materials should be re-evaluated when the theory itself is re-evaluated.

I think we should be clear on what is being re-thought here. The theory of evolution itself, that variation and descent, combined with selective pressure, will lead to complex organisms with the appearance of design, is not being rethought. The theory that evolution via natural selection is responsible for the diversity of species of life on earth is not being rethought. All that is being rethought is the particular history regarding the evolution of mammals. That the theory of evolution can be used to exp

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[Fordiman (689627)]

Summary:
Evolution, the historical record of species evolution on earth is being rethought, as there is new evidence to refine our understanding of it, and is as yet theoretical.

Evolution, the process of speciation (the forking off of species) and adaptation through natural selection, is quite firmly proven.

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[rucs_hack (784150)]

Your analogy of a freak accident isn't far wrong. It is a mistake to think of evolution as a planned process. That's where a lot of creationists try to poke holes in it by saying "what's the use of half an eye" The argument makes the assumption that an eye was the intended goal, but there was no intention.

It goes like this. Animal A and animal B are attacked by animal C. Animal A has some cells on its skin that are light sensitive, even if only a tiny bit. Neither A B or C have eyes, so animal A escapes bec

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[rucs_hack (784150)]

alas putting the argument initially in such a confrontational way doesn't help.

You need to get them to really debate. Most won't, and spout the same stuff over and over.

Thing is, two centuries ago everyone was a creationist, we would have been as well, there was no alternative. They are however fighting a losing battle if you look at the numbers. It will likely be another century before creationism is dead, and then only maybe.