I was into dinosaurs when I was a kid, and now I’m teaching my kids about dinosaurs. In light how much our understanding of dinosaurs has drifted in 30 years, and after learning about how certain dinosaurs species are basically extrapolations based on, like, a single bone, I’m trying to get a sense of what we actually know about dinosaurs versus what is just being made up to fill in the gaps.
As an example of what I’m talking about, the wing span for quetzalcoatlus keeps being revised downward. They seem to have a few skeleton fragments, and then they extrapolated what the rest of the skeleton looked like based on other species which they assume to be similar. I find myself wondering if at some point they’re just going to come out and say, “Yeah, this thing never flew at all, the assumption that it was just a bigger version of other azhdarchid species was completely wrong, sorry.” Sometimes I read passages that suggest that pterodactyls may not have been fliers at all.
We’ve seen many similar revisions, such as the famous “T. Rex was a scavenger” and “all these dinosaurs had feathers”. So if I had a pithy version of this “stupid question” it would be “What do we actually know about dinosaurs?”
I think that the basic answer is that they were really big, and looked kind of like dinosaurs. We certainly know more than that, but most of what we know is either highly technical, or just deductions that you might not want to consider “really knowing”. There is also a third category, with things like “laid eggs” and “underwent a mass extinction event” that you already know and are probably not interested in hearing about again.
It is worth noting that although they were the dominant land animal for about 135 million years, we only have about 1,000 clearly identified species (to help put this in perspective, we have two clearly defined species identified in the genus Triceratops, one of the most recent of the dinosaur genera… as opposed to, for example, about 30 species for the genus Homo {not a very prolific genera}. These two genera, Triceratops and Homo, spent approximately the same amount of time on planet Earth.) It is possible that the less than 1% of dinosaur species that we happen to have stumbled across are a good representative sample of the clade, but it is also possible that they are not.
But… We do know that many dinosaurs had feather-like structures. We do know that T. Rex could eat you, even if you were hiding in your car, and there is some evidence of them attacking live prey (prey that escaped with wounds that were able to start healing before they died). Pterodactyls could fly, although some early scientists in the 17-1800s doubted this, and for a while it was believed to be a swimmer. (But pterodactyls are not technically dinosaurs).
Studying dinosaurs is still just peeking at the very edge of a very large and mysterious world, and that is probably more useful for kids to learn about than hunting down the few facts we know for sure. But I do agree that the information out there is not presented very well; it should all be in the form “we think X because of Y”, but it is generally boiled down for popular audiences to something like “MAYBE X!”
I was into dinosaurs when I was a kid, and now I’m teaching my kids about dinosaurs. In light how much our understanding of dinosaurs has drifted in 30 years, and after learning about how certain dinosaurs species are basically extrapolations based on, like, a single bone, I’m trying to get a sense of what we actually know about dinosaurs versus what is just being made up to fill in the gaps.
As an example of what I’m talking about, the wing span for quetzalcoatlus keeps being revised downward. They seem to have a few skeleton fragments, and then they extrapolated what the rest of the skeleton looked like based on other species which they assume to be similar. I find myself wondering if at some point they’re just going to come out and say, “Yeah, this thing never flew at all, the assumption that it was just a bigger version of other azhdarchid species was completely wrong, sorry.” Sometimes I read passages that suggest that pterodactyls may not have been fliers at all.
We’ve seen many similar revisions, such as the famous “T. Rex was a scavenger” and “all these dinosaurs had feathers”. So if I had a pithy version of this “stupid question” it would be “What do we actually know about dinosaurs?”
I think that the basic answer is that they were really big, and looked kind of like dinosaurs. We certainly know more than that, but most of what we know is either highly technical, or just deductions that you might not want to consider “really knowing”. There is also a third category, with things like “laid eggs” and “underwent a mass extinction event” that you already know and are probably not interested in hearing about again.
It is worth noting that although they were the dominant land animal for about 135 million years, we only have about 1,000 clearly identified species (to help put this in perspective, we have two clearly defined species identified in the genus Triceratops, one of the most recent of the dinosaur genera… as opposed to, for example, about 30 species for the genus Homo {not a very prolific genera}. These two genera, Triceratops and Homo, spent approximately the same amount of time on planet Earth.) It is possible that the less than 1% of dinosaur species that we happen to have stumbled across are a good representative sample of the clade, but it is also possible that they are not.
But… We do know that many dinosaurs had feather-like structures. We do know that T. Rex could eat you, even if you were hiding in your car, and there is some evidence of them attacking live prey (prey that escaped with wounds that were able to start healing before they died). Pterodactyls could fly, although some early scientists in the 17-1800s doubted this, and for a while it was believed to be a swimmer. (But pterodactyls are not technically dinosaurs).
Studying dinosaurs is still just peeking at the very edge of a very large and mysterious world, and that is probably more useful for kids to learn about than hunting down the few facts we know for sure. But I do agree that the information out there is not presented very well; it should all be in the form “we think X because of Y”, but it is generally boiled down for popular audiences to something like “MAYBE X!”
Monty Python—Theory on Brontosauruses