New study rebuts 75-year-old belief in reptile evolution

In it, researchers show that the evolution of extinct lineages of reptiles from more than 250 million years ago took place through many small bursts of morphological changes, such as developing armored body plans or wings for gliding, over a period of 50 million years instead of during a single major evolutionary event, as previously thought. They also show that the early evolution of most lizard lineages was a continuously slower and more incremental process than previously understood.

Further evidence that contradicted adaptive radiation included similar but surprising findings on the origins of snakes, which achieved the major aspects of their skinny, elongated body plans early in their evolution about 170 million years ago (but didn’t fully lose their limbs for another 105 million years). They also underwent rapid changes to their skulls about 170 to 165 million years ago that led to such powerful and flexible mouths that today they can swallow whole prey many times their size. But while snakes experienced the fastest rates of anatomical change in the history of reptile evolution, these changes did not coincide with increases in taxonomic diversity or high rates of molecular evolution as predicted by adaptive radiations, the researchers said.


You have to stop relying on press release hype. Here is the actual paper. It’s an interesting and complex story, and I shudder to imagine what you may have made of it.


She directed to an interesting article. I’d be curious your take on the details @John_Harshman.


Thanks. I thought about searching for the actual paper but was feeling lazy, and was helping my son with an art project and assumed someone would do so if they felt it necessary to discuss.

Generally I thought it was interesting and knew this group would be interested in it.

I did wonder how long God cursed the serpent to creep with legs still attached before it evolved into the snake we’re more familiar with. How embarrassing to have legs you can’t use. :joy: Since we were discussing Eden and the fall in the forum that came to mind.

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Even though your comment is tongue-in-cheek, many Christians do assume that Genesis claims that all snakes were “cursed” to slithering on the ground because of what happened in the garden in ancient Eden. Yet, if they read Genesis 3 closely, it is only “the serpent” which tempted Eve that is told:

"Because you have done this, “Cursed are you above all the livestock and all the wild animals! You will crawl on your belly and you will eat dust all the days of your life. And I will put enmity between you and the woman, and between your offspring and hers; he will crushyour head, and you will strike his heel.”

Of course, populations evolve but not individual animals. And Genesis 3:14 says nothing about any descendants of the Serpent.

I agree. It also doesn’t rule out the possibility.

I’ve found that with @thoughtful you can’t trust that interpretation. She could have meant every bit of it. No way to tell.

Apparently you don’t understand the “just-so story” genre. There was only one Elephant’s Child, but still all elephants have trunks. There was only one Eve, but all women have pain in childbirth. And so on.


Actually, it doesn’t seem all that surprising to me. First some species evolves a new trick, then that species spreads all over, speciates a lot, and becomes a big clade. Perhaps the lag between step A and step B is larger than previously imagined, but the sequence seems as expected.

The decoupling of rates of morphological and molecular evolution also wouldn’t be surprising.

It’s a fine study based on lots of data, and it has rigorous measures of some interesting relations among parameters, but I guess you have to really hype things up to get into Nature, even Nature Communications.

One odd thing: their tree contradicts the current consensus on the position of turtles (living sister group of archosaurs) and makes them instead the living sister group of diapsids. I wonder what effect that has on the analysis.

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You’re right. Some of the time what I write is a little bit of tongue-in-cheek and utter seriousness at the same time. Eek. Not sure how that’s possible, but if my comments can be read both ways, you’ve probably got my meaning. But @John_Harshman you especially bring that out in me. No idea why. Sorry. :see_no_evil:

Yes. I was also thinking that in the text you also have similar “just-so” pronouncements - and it’s later clarified by the New Testament the seed of the woman and seed of the serpent is more than one generation, and all the curses of Genesis 3 are permanent until reversed by Christ. You also have the snake on the pole for healing of snake bites in the wilderness - the symbol of medicine. So all of that seems to imply the curse extends to all snakes.

I don’t believe you are. Some may find your caprice and tendency to nonsense charming, but others may not. You should understand that.


Geez. Be nice.

Passive-aggressive needs to be pointed out.


You made me smile - I wasn’t sure if anyone found me charming. :grinning: I’ll take that compliment as an indication you may be beginning to like me.

Ogres do like odd ducks; I wasn’t sure if it held true the other way around.

Edit. This is a serious comment. :rofl:

Don’t be too quick. I said “may”, and I wasn’t referring to myself.


I enjoyed the comment because - as I have said, my husband has autism, hence no filter: Reading something about myself that had nuance and refers to what others think was a refreshing change of pace. And the criticism wasn’t wholly undeserved.

Silliness in our household often relieves tension, and life is too hard not to have fun sometimes. Science and conversation about it is not a sacred cow - at least not to me.

But if you criticize the character of my God, or seem to attack Him, I will take that very seriously. But I try to be a little silly to say that doesn’t mean I don’t like you; you just don’t know Him.

Yes, that’s very similar to the way I just don’t know Atticus Finch, or Indiana Jones, or the Tooth Fairy.

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