Beware of Movies! Other Planets, Other Worlds

The Beware of Movies! series is meant to point out some of the scientific inaccuracies of popular movies, specifically in points related to the geological sciences.

This post will point out the major inaccuracies portrayed in movies about the rest of the universe. What do we know about the other planets in the solar system, or the whole universe? How do we know this? Could there be life on other planets? If so, what would it be like? Continue reading

Beware of Movies! Climate Change

The Beware of Movies! series is meant to point out some of the scientific inaccuracies of popular movies, specifically in points related to the geological sciences.

This post will point out the major inaccuracies portrayed in movies about climate change, and how it would affect the Earth.

Climate change is a sensitive topic. It’s become politically charged. It’s now taboo to talk about it in polite company. I’m not here to incite riots. I have my opinions that, though I won’t state them explicitly, they’ll probably be obvious. My objective here is to talk about how we understand climate change, how we can infer that it is happening. I want to demystify all the numbers and data points and graphics that we’re bombarded with every day. Continue reading

Beware of Movies! Fossils and Paleontology

The Beware of Movies! series is meant to point out some of the scientific inaccuracies of popular movies, specifically in points related to the geological sciences.

This post will point out the major inaccuracies portrayed in movies about the science of paleontology. I’m a paleontologist. This oughtta be good…

Commonly, about two seconds after I tell someone I’m a vertebrate paleontologist, they ask me what I think of Jurassic Park. Then I laugh. It’s either that or they ask me if I carry a whip like Indiana Jones. Then I snarl something about how 1) Dr. Jones was an archaeologist and 2) Indiana was the dog!

Continue reading

Beware of Movies! Meteorites and Magnetism – More on the Earth’s Interior

The Beware of Movies! series is meant to point out some of the scientific inaccuracies of popular movies, specifically in points related to the geological sciences.

This blog post will point out the major inaccuracies portrayed in movies about the Earth’s composition and its magnetic field.

Today (January 15, 2013) I presented a Beware of Movies lecture at a local retirement community. The focus was on the Interior of the Earth, and was the topic of an earlier blog post. It was a wonderful experience. (I love doing those things!) In the process of preparing, then delivering, the presentation, I did realize that I left a few critical things out. Hence, a new blog post!

Meteorites — What do they have to do with the Earth’s interior?

One of the big problems that arises with bad geology movies is that they get the composition of the Earth all wrong. There aren’t amethysts in the mantle. Diamonds and rubies would not co-exist. We know that the mantle of the Earth is composed of mafic and ultra-mafic rocks (think back to Bowen’s Reaction Series). That means it’s mostly low-silica, high iron and magnesium rocks down there. Even deeper, we know that the core is composed mostly of iron and nickel.

As we stand on the Earth’s surface, such minerals and rocks are rare. It’s easy to think that most of the rocks of the Earth should be felsic things like granite, with tons of quartz. This is simply not the case.

But why? How can we make the assumption that the mantle is mafic and the core is iron and nickel. We know some of this because there are a few places on Earth where mantle rocks have been exposed at the surface (usually due to tectonic events). We can hypothesize some compositions based upon how seismic waves refract through the body of the Earth (seismic waves travel at different rates through different materials).

We can make some assumptions about the overall composition of the Earth based upon studies of meteorites. We assume that the bits of rock and dust that collected all those billions of years ago to form our beloved planet formed from the same bits of rock and dust that make up meteorites. If you take a meteorite and grind it up, you find it to be of mafic composition, with low silica, and high concentrations of iron, magnesium, and nickel. Some meteorites are almost pure nickel and iron. Others are more rocky. This is assumed to be the starting point for the Earth’s composition.

A Chondrite – a very primitive stony meteorite. Photo by H. Raab

A polished surface of an iron meteorite – photo by Opsoelder

Over millions of years, these mafic pebbles that came together to form the planet fused, and then underwent a process called ‘differentiation,’ which is just a fancy way to say ‘the heavy stuff went to the middle.’ Thus, the nickel and iron are at the core of the Earth, surrounded by the mantle of mafic rocks. Felsic rocks, like granite, tend to be light and naturally ‘float’ to the surface, which is why they are what we usually see in the rocks around us!

Magnetism — The Earth isn’t exactly a giant bar magnet, but it’s similar.

Here’s the neat thing about the core. It’s iron and nickel. Iron is a conductor. If you have an electrical current, you have a magnetic field. And voila! The Earth has a magnetic field.

The core is divided into two parts, the liquid outer and the solid inner. The mantle is also solid. Because the Earth rotates, flow is set up in the Earth’s liquid outer core. With that flow, and a little nudge, an electric current is set up. The flow is thought to be in several isolated cylinders surrounding the solid inner core. This is where the ‘bar magnet’ analogy fails, because each cylinder has it’s own field, and these combine to form the magnetic field of the Earth. This is referred to the geomagnetic dynamo.

Geomagnetic dynamo. All this is happening in the core.

Because of the dynamic nature of flow in the core, the magnetic pole never quite lines up the the Earth’s rotational axis. In fact, the magnetic poles move around quite a bit, sometimes even reversing themselves (though this takes more than a single human’s lifetime). There are lots of questions regarding how the magnetic field forms and how it might reverse itself, and is an active field of research in geophysics.

Beware of movies! The basis of the entire movie “The Core” is that the flow in the liquid outer core has stopped, thus causing the Earth’s magnetic field to fail. If we did lose the magnetic field, there could be repercussions, however, the magnetic field on Earth has gone essentially to zero multiple times in Earth’s history. Every time the magnetic poles reverse themselves, the field goes to zero first. While there is some evidence that this might have caused problems for certain single-celled organisms, large animals have not been affected. The cataclysms that are shown in the movie would not be expected. So don’t worry.

Bad Geology Movies: Caveman, 1981



Ringo Starr, Dennis Quaid, Barbara Bach

Premise: Could the awkward defeat the hulking in one zillion BC?

Caveman has got to be one of my all-time favorite movies. I liked it when I was a kid, because it was just plain silly. As I got older, I liked it because it had Ringo Starr in it (I was a Beatles fan – I guess I still am!). As an adult, I’m entertained by the subtext. (Zug-zug!) And as a paleontologist, I am wildly entertained by all the inaccuracies.

It’s comedy, so of course it’s fraught with inaccuracy. A lot of it is intentionally blatant. That’s what makes it funny. Because this movie is billed as comedy, any intelligent person knows better than to believe anything in it. I’ll just point out the paleontological silliness and warn you that if you haven’t seen this movie before, there are lots of spoilers ahead!

It opens with a big guffaw. One zillion B.C. it reads on the screen. Zillion isn’t even a proper number, but it is certainly much larger than a billion, thus exceeds the known age of the Earth (even back in 1981).

Setting— Everything about where the movie was shot, down to the tar pits, says California. Well, cavemen were not kicking around in California. They were in Europe.

Dinosaurs and humans— What were they even doing there? Dinosaurs and humans never co-existed. They missed each other by at least 60 million years.

The Dinosaurs themselves— Only two dinosaurs were depicted. One was a lizard-y guy with spikes on his back and tail and a big pointy horn. This guy also had chameleon-like eyes that moved around this way and that. He also had a sprawling stance (his legs out to the side like an alligator). This was clearly made up. This could be a take on the original interpretation of Iguanodon, but I think it was just made up for the sake of the show.

The original (now known to be inaccurate) reconstruction of Iguanodon – Photo by mugly on Flickr

The other dinosaur was Tyrannosaurus rex (I assume). This version of T. rex is a nod to the original interpretation of the dinosaur, with the body held vertically and the massive tail resting on the ground. This is in marked contrast with the interpretation of T. rex in Jurassic park, which itself is totally different from modern depictions of the beast. These days, T. rex is seen as a fleet-footed predator that held its body horizontally and its tail straight out behind. The modern view of T. rex also includes feathers.

The Tyrannosaurus of Caveman is a talented dinosaur, however, able to emulate howling wolves, crowing roosters, and hooting owls. It’s actually worth a bit of a chuckle to think that the crowing and hooting aren’t so far off from possible, given that modern birds are thought to be the closest living relatives to dinosaurs, especially theropods like T. rex.

The pterosaur and the giant egg— Pterosaurs and humans never co-existed either. Though not dinosaurs, pterosaurs lived during the same time and went extinct at the same time as dinosaurs. The giant egg was clearly too large to have been laid by the pterosaur that we see flying around in the movie, but it sure lends itself to a hilarious sequence of events.

A nearby ice age…— This is hilarious because we know it ain’t possible. An ‘ice age’ is a time period, not a place, and certainly, no-one is going to walk from the desert to a frozen wasteland in one day. Nevertheless, the snow beast is adorable and you just have to feel for him. Maybe he was just trying to make friends.

My favorite part of this movie has nothing to do with paleontology. I love the bit where Atouk’s little tossed together tribe has an impromptu fireside music, song, and dance fest. It just makes me happy.

Bad Geology Movies: Dinosaur, 2000



D.B. Sweeney, Julianna Margulies and Samuel E. Wright

Premise: What would happen if a dinosaur was raised by lemurs?

OK. This is totally a kids’ movie. I won’t say anything about talking dinosaurs. And I know there has to be tons of artistic license. Fine. Nevertheless, there are some things about this movie that are terribly inaccurate.

But I only took two pages of notes, and, admittedly, the pencil was blunt and there were pictures. So there’s not too much.

Dinosaurs that I recognized: Iguanodon (e-K), Carnotaurus (l-K), An Oviraptor (Rinchenia) (l-K), Velociraptor (l-K), Brachiosaurus (l-J), Styracosaurus (l-K), Ankylosaurus (l-K), Parasaurolophus (l-K), Struthiomimus (l-K)

Those funny little parenthetical bits there denote the age of rocks in which each of these animals are typically found. (l-K) means the late Cretaceous, just before the dinosaurs went extinct. Luckily, most of the animals depicted in the movie are from the late Cretaceous. That makes sense. The whole movie begins with an asteroid impact which, presumably, represents the one that killed off the dinosaurs at the end of the Cretaceous.

There are a couple of problems though. For one, the main character is an Iguanodon. Iguanodon lived in the early Cretaceous (e-K). That could be 50-70 million years before the rest of the characters. But if that’s not bad enough, Brachiosaurus is from the late Jurassic (l-J), which is tens of millions of years older than that.

So, these animals never actually co-existed.

Lemurs, or any modern primate did not appear on the Earth until at least ten million years after the dinosaurs went extinct. So that just wouldn’t happen. But fuzzy animals with goofy personalities are great for the show.

There are some other bits that were worrysome: Why are the lemurs on an island separated from the mainland? Why aren’t there dinosaurs on that island? How come the nesting grounds are unaffected by the meteor impact? Why are all the dinosaurs essentially sentient, except for the poor ankylosaur?

That landslide was a little sketchy, too. Where did that rock come from?

Oh, and hey. Why did any dinosaurs survive? After all, didn’t the asteroid wipe them out at the end of the Cretaceous? In the end, this is actually OK. Maybe some relict populations did survive beyond the end of the Cretaceous, but died out soon thereafter. There’s even some evidence that this occurred, though most paleontologists are skeptical. The point is that it is plausible that not everything died immediately after the impact.

Besides, it’s a kids’ movie. What do you want?