No, Sauropods Did NOT Once Walk on Their Front Legs

I recently came upon a Fox News article titled Giant ‘thunder lizard’ dinosaurs may have walked on their front feet only. No, really!

Gigantic sauropods, some of the largest creatures to ever roam the Earth, apparently once walked only on their front feet.

The huge dinosaurs, which include the Brontosaurus and Brachiosaurus, among others, are thought to have needed all four of their thick legs to support their oversized bodies.

A new study, which refers to the dinosaurs as “thunder lizards,” offers support for a somewhat controversial view among scientists: that these giants were able to move around on only two legs at certain times.

Wait, what now?

I knew immediately that there was no way this claim could possibly be true. Sure, Sauropods in Jurassic Park sometimes got up on their hind legs, but forelegs?! No way! Trying to even get a mental picture of what that might look like was nearly impossible.

And so I did what I so often do when reading things that seem like they can’t possibly be true in science journalism articles: I pulled up the actual study. Here is the abstract:

Three parallel, manus-only sauropod trackways from the Coffee Hollow A-Male tracksite (Glen Rose Formation, Kendall County, Texas) were studied separately by researchers from the Heritage Museum of the Texas Hill Country and the Houston Museum of Natural Sciences. Footprint and trackway measurements generally show good agreement between the two groups’ data sets. … Greater differential pressure exerted on the substrate by the forefeet than the hindfeet probably explains the Coffee Hollow trackways, like other manus-only sauropod trackways, but the possibility that they indicate unusual locomotion cannot at present be ruled out.

That … does not say that giant sauropods once walked only on their front feet. It does not say that at all. Because it’s unclear what “unusual locomotion” means, though, I tracked down the full study, and let me tell you, it is fascinating. (That’s not sarcasm, I like scientific papers.)

Here is how the discussion section begins:

Explanations for manus-only sauropod trackways fall into two categories: preservational or formational artefacts in prints created during normal walking (differential pressure exerted by the manus and pes on the substrate) or unusual behaviour (‘swimming’). In the spirit of multiple working hypotheses, we now consider the pros and cons of each of these interpretations as applied to the Coffee Hollow A-Male manus only sauropod trackways.

In other words, the question researchers asked was whether the sauropods were putting extra pressure on their front legs, which, combined with the particular substrate they were walking in, resulted in only those footprints being preserved, or whether the sauropods were swimming in shallow water, leaving prints with their front legs as their back legs floated.

Let’s be clear: literally no one is suggesting that these sauropods walked on their front legs. “Unusual locomotion” refers to swimming, not to walking on their front legs.

There are a whole lot of charts and graphs in this paper. There’s even a picture:

The researchers note that “front-heavy” sauropods would both be more likely to leave tracks with heavier front foot impressions and likely to “punt” with their forelimbs while in water a few meters deep. This leaves them unable to say which scenario the prints were made by.

Ironically, then, it might be that discovery of manus-dominant sauropod trackways in the Glen Rose Formation would not only make a differential pressure explanation for manus-only sauropod trackways more plausible, but also be a prerequisite for supporting the hypothesis that manus-only trackways could have been made by punting sauropods! The best evidence for forefoot-supported punting sauropods would therefore be discovery of trackways in which pes prints were absent, but the manus prints were fairly deeply impressed, indicating a soft substrate in which pes prints would likely have registered, had the dinosaurs actually been normally walking rather than punting. This is not true of the shallowly impressed Coffee Hollow A-Male trackways.

In other words, if you could find deep front foot sauropod prints in absence of back foot prints, you could probably conclude with some certainty that this indicated a sauropod that was punting (swimming using its legs) in water. The tracks they examined were shallow. As a result, researchers were unable to conclude whether the prints were (a) made on land and preserved unevenly due to pressure differentials between the limbs, or (b) made under water, but in ground that wasn’t soft enough for the punting forelegs to leave particularly deep impressions.

Guess what? I perused the whole article and never once do the researchers suggest that these sauropods walked on two legs. Never once.

Having read the actual scientific journal article, I returned to read the rest of the Fox News article, and it is so bad. Having starting with a blanket assertion that sauropods once walked the earth on their two forelegs, the article goes on to quote someone in 1940 who suggested that front leg only sauropod tracks could have been made in water. After this, the article gives a nod to current experts’ suggestion that the prints may be result of front-heavy sauropods putting more weight on their forelimbs. Then, amazingly, the article finishes with these lines:

“Greater differential pressure exerted on the substrate by the forefeet than the hindfeet probably explains the Coffee Hollow trackways, like other manus-only sauropod trackways, but the possibility that they indicate unusual locomotion cannot at present be ruled out,” the authors wrote in their paper’s abstract.

The researchers told Science Alert that future discoveries will be needed to settle the matter once and for all.

That reference to “unusual locomotion” in the paper’s abstract is a reference to punting in water, not a reference to sauropods walking on their forelimbs. The author of this article came to the conclusion that scientists are considering the possibility that sauropods sometimes walked on their front legs only because of the words “unusual locomotion” in the study’s abstract. That’s literally all he’s going on. He does not quote a single scientist saying that.

Lest you think I’m just dunking on science journalists, at least one got it right. Unusual Dinosaur Footprints Suggests Giant Sauropods Waded Through Water On Front Legs, reads the title of an article on IFL Science. That article is very clear from the outset:

The idea that these massive creatures walked on two legs, and those being the front legs rather than the hind, is absurd, experts say.

If you want to know more, that article is actually worth a read.

I did learn something from this ridiculous reporting, though. I learned that Answers in Genesis only reads science journalism summaries of scientific papers, and not the papers themselves. But you don’t have to take my word for it! Did Sauropods Walk on Two Legs? reads the title of an article written by Ken Ham. (Again, no one is suggesting that. No one.)

Ham writes as follows:

Sauropods—the “long-necked” dinosaurs—are among the largest and most famous of the dinosaur kinds. Naturally, scientists have assumed the massive creatures needed all four legs to support their enormous weight. Now a new study on three sets of front-leg-only sauropod tracks uncovered in Texas is challenging that assumption.

No! No it is not!

It is perhaps telling that Ham links not to the study itself but to the Fox News article, which proclaims (falsely) that scientists are considering whether sauropods perhaps walked on their forelegs. Ham, it is clear, did not read the original source himself, only the Fox News article.

Ham goes on:

The tracks appear to have been made by only the front two feet of sauropods three times in parallel. In this new study, the researchers conclude that, at certain times, the sauropods could move on their front feet, instead of all four feet.

No, the researchers do not “conclude that, at certain times, the sauropods could move on their front feet, instead of all four feet.” They in fact concluded that they could not say for sure whether the tracks were made due to a pressure differential—more weight being placed on the forelegs, resulting in only those prints being preserved—or due to punting in water.

Once again, Ham goes on:

This could be because the giant creatures were swimming, as some have proposed, or as this new study argues, it could be an unusual form of locomotion or merely the result of a weight differential. If the front limbs support more weight than the rear legs, perhaps, on certain surfaces, only the front limbs leave a print.

Note that Ham places the “some” who have proposed that the sauropods were swimming in contrast with this study, which Ham claims argues that “it could be an unusual form of locomotion or merely the result of a weight differential.” (Ham does not come back to the question of the weight differential.) And for the last time, the “unusual form of locomotion” the researchers reference in the abstract was punting in water.

Look, let me quote that bit from the original study again:

Explanations for manus-only sauropod trackways fall into two categories: preservational or formational artefacts in prints created during normal walking (differential pressure exerted by the manus and pes on the substrate) or unusual behaviour (‘swimming’). In the spirit of multiple working hypotheses, we now consider the pros and cons of each of these interpretations as applied to the Coffee Hollow A-Male manus only sauropod trackways.

Ham very clearly did not look at the actual study. All he did was look at the Fox News article that covered the study as science journalism articles so often do—with great hype and false or misleading assertions. If Ham were a legitimate scientist, he would know that he needs to go to the source. But he is not, and he does not, and this is the result.

Ham claims (falsely) that scientists are considering whether sauropods might have sometimes walked on the earth on their front legs (contrary to, you know, physics and gravity). He thinks it is amusing that “evolutionists” could be so stupid as to believe something like this. He argues that young earth creationism and flood geology provides the actual answer to these prints.

Ham writes as follows:

[T]hese sauropod trackways likely represent creatures fleeing the rising floodwaters, perhaps trying to swim or otherwise climb to higher ground to escape. These tracks were found in the Lower Cretaceous, which is flood rock. Of course, because secular scientists reject the Bible’s history, they reject the global flood and so they won’t consider this option.

Take that, evolutionists!

Ham’s entire piece is predicated on the false claim that researchers would rather consider that sauropods could walk on the ground on their forelegs than consider that these prints could have been left by sauropods moving in water, when in fact much of the study he’s responding to is taken up with a discussion of these prints possibly occurring by sauropods punting in water. 

You know what’s really funny? If Ham had read the actual study, he could have celebrated it as a confirmation of his flood narrative. See! There are dinosaur prints that even evolutionists admit were made by creatures fleeing floodwaters! (Well, that’s not quite what the study says, but at this point I’m past expecting him to ever be completely honest.) This is a study that confirms Ham’s flood narrative—or rather, that he would see as confirming his flood narrative—but he doesn’t know that, because he couldn’t be bothered to read the damn study.

I’ll finish with one simple question. If the Lower Cretaceous was laid down during a catastrophic global flood with raging currents and ash raining down from heaven, and if sauropods fleeing through water were likely to leave only front leg prints as they frantically sought safety, why are front-only sauropod prints so comparatively rare in that strata (and they are rare)? If essentially all dinosaur prints were laid down during the flood, as Answers in Genesis claims, wouldn’t we expect front leg only prints to be the norm—or at least common—rather than the exception?

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