Blog

While the grub itself may be long gone, a record of dinosaurs’ favorite foods has been stowed away in their ancient tooth enamel over the last eon. When researchers at The University of Texas at Austin took a close look, they discovered that some dinosaurs were discerning eaters, with different species preferring different plant parts.

Tooth enamel contains calcium isotopes that reflect the range of foods the dinosaurs ate; different types of plants have different chemical signatures, and discrete parts of trees — from buds to bark — can also have unique signatures. According to the study’s lead author Liam Norris, the results help explain how so many behemoth creatures all lived together in the same area at the same time.

“The ecosystem that I studied has been a mystery for a long time because it has these giant herbivores all coexisting,” said Norris, a recent doctoral graduate at UT’s Jackson School of Geosciences. “The idea is that they were all eating different things, and now we have found proof of that.”

The findings were published in Palaeogeography, Palaeoclimatology, Palaeoecology.

Norris inspected teeth from four dinosaur species and one crocodyliform, both herbivores and carnivores, that roamed the Western U.S. during the Late Jurassic. The plant-eaters are the long-necked Camarasaurus; the short-armed Camptosaurus; and the trunk-legged Diplodocus. The meat-eaters are the bipedal Allosaurus and the comparatively small, crocodile-like Eutretauranosuchus. The bones and teeth of these ancient creatures were all found in the Carnegie Quarry deposit in northeast Utah, which is thought to have formed during an extreme drought in as little as six months to a few thousand years.

“We were very lucky to be able to study fossils of dinosaurs that lived together and were all rapidly preserved in a single deposit,” said Rowan Martindale, an associate professor at the Jackson School’s Department of Earth and Planetary Sciences. “The Jurassic tomb preserved a unique paleontological gem and these skeletons are beautifully displayed at Dinosaur National Monument.”

Norris, who now works at the Texas Science & Natural History Museum, studied teeth from 17 individual animals across these five species. The specimens were loaned by the Utah Field House of Natural History State Park Museum or accessed in the field at Dinosaur National Monument. He shaved off a dusting of their enamel, which he took back to the Jackson School for calcium isotope analysis. Jackson School Professor John Lassiter and Radiogenic Isotope Laboratory Manager Aaron Satkoski, both co-authors on the paper, helped to analyze and interpret these data.

Previously, scientists believed that large herbivorous dinosaurs coexisted by munching on different levels of the tree canopy according to height. However, Norris’s research shows that plant height wasn’t the only factor driving the differentiation of their diets — instead, it was specific plant parts.

For example, Norris found that the Camptosaurus was a rather discerning eater, preferring softer, more nutritious plant parts such as leaves and buds. The Camarasaurus ate mostly conifers, with a preference for woody plant tissues. The Diplodocus ate more of a mixed diet that included soft ferns and horsetail plants lower to the ground, as well as tougher plant parts.

“This differentiation in diet makes sense with what we see from the morphology of these animals: the different height, the different snout shape. Then, we bring in this geochemical data, which is a very concrete piece of evidence to add to that pot,” Norris said.

This research also provides interesting food for thought to a theory about long-necked dinosaurs having flexible necks that could be used to reach many areas of vegetation without having to expend the energy to move the rest of their body. This research, which shows that the dinosaurs ate from different levels of the tree canopy, furthers that line of thinking.

The carnivores in the study — the Allosaurus and Eutretauranosuchus — had an overlap in calcium isotope values, which could mean that they ate some of the same things. However, the results also showed that the Eutretauranosuchus is more likely to have eaten fish, while the Allosaurus primarily ate herbivorous dinosaurs — possibly including the three other dinosaur species mentioned in this study.

For this ancient ecosystem to have supported so many enormous dinosaurs with such specific dietary proclivities helps to paint a picture of the vegetation and plant productivity of the time.

“It’s really just more proof that this ecosystem was as spectacular as we thought it was,” Norris said.

Henry Fricke of Colorado College also co-authored the study.

“Hearst Magazines and Yahoo may earn commission or revenue on some items through these links.”

Here’s what you’ll learn when you read this story:

• In 1956, physicist David Pines theorized the existence of a massless, neutral plasmon called a “demon” that could help explain the superconductivity of some exotic materials.

• Now, scientists at the University of Illinois Urbana-Champlain have found evidence of this theorized demon in the metal strontium ruthenate.

• Because this demon likely exists at room temperatures, this discovery could help scientists better understand high-temperature superconductors.

---

Condensed matter physicists from the University of Illinois have successfully summoned a demon, but probably not the one you’re picturing—think less fire and brimstone and more quantum mechanics trickery. The “demon,” in this case, actually stands for “distinct electron motion” with the physics favorite suffix “-on” added for good measure.

Theorized by physicist David Pines in 1956, this demon (also known as Pine’s Demon) is a plasmon—a discrete wave rippling through plasma electrons—that is massless and has a neutral charge. As you’d probably imagine, something that’s both massless and neutral isn’t exactly easy to detect.

But a paper published by scientists at the University of Illinois showcases how they stumbled upon this demon plasmon by accident. At first, the team was only analyzing the metal strontium ruthenate to figure out why it contained similar properties to high-temperature superconductors (around -130 degrees Celsius) without actually being one. Then, they spotted a quasiparticle that was too slow to be a surface plasmon but too fast to be an acoustic phonon.

“At first, we had no idea what it was. Demons are not in the mainstream. The possibility came up early on, and we basically laughed it off,” co-author Ali Husain said in a press statement. “But, as we started ruling things out, we started to suspect that we had really found the demon.”

To find the demon, the team fired electrons off a crystal of the metal strontium ruthenate and measured energy gain with an incredibly high precision. Using this energy data, scientists could then track the demon’s momentum within the material until finally discovering that the quasiparticle closely matched Pine’s 67-year-old predictions of a massless electronic mode, or demon. The results were published in the journal Nature.

“It speaks to the importance of just measuring stuff,” Peter Abbamonte, physics professor at the University of Illinois Urbana-Champlain and co-author, said in a press statement. “Most big discoveries are not planned. You go look somewhere new and see what’s there.”

The discovery of a demon is particularly important for understanding superconductors. Because this quasiparticle is massless, it can form with any energy and potentially at any temperature.

The standard theory of superconductors, known as the BCS theory, attributes superconductivity to an interaction between electrons and phonons, the natural vibrations given off by an atomic crystal lattice. However, the BCS Theory can’t always explain the zero energy resistance of high-temperature superconductors, which suggests some materials achieve superconductivity through other means. One of these means could be this newly discovered demon quasiparticle, as they’ve been theorized to play a role in a semimetal’s transition into superconductivity.

The first step in any breakthrough is to first face your demons—hopefully, the same can be said for superconductors as well.

Get the Issue

Get the Issue

Get the Issue

Get the Issue

Get the Issue

Get the Issue

Get the Issue

Get the Issue

Get the Issue

You Might Also Like

SpaceX has lots of enemies — but this may be the most unexpected yet.

As Space.com reported, members of the American Association for Nude Recreation (AANR) — yes, that’s a real group — were among those protesting the Elon Musk-owned company’s proposed use of Kennedy Space Center on the Sunshine State’s so-called Space Coast.

Among the many potential impacts associated with bringing SpaceX to Florida — including hearing damage to local residents and flight delays across the state, per various opponents — is the repeat closure of Playalinda Beach, a remote location on the Canaveral National Seashore that’s one of Florida’s four main public beaches where nudity is legal.

Popular among the clothing-optional set, Playalinda could be closed up to 60 times per year due to Starship operations — and Deborah-Sue Stevens, a former regional director for the nudist organization’s Western branch, says those closures will harm many members of her community.

“[There are] probably a quarter million people that travel and think like I do,” Stevens said, calling into the Zoom meeting from California, “who look for destinations that are beautiful and surrounded by like-minded people.”

Erich Schuttauf, the executive director of AANR — which bills itself as the largest and longest-established nudist organization in the US with foundations dating back to 1931 — added that Playalinda closures might affect the non-nude community too.

As Schuttauf explained, nudists may end up traveling to nearby Volusia County, whose clothing-optional Apollo Beach, located further along the Canaveral shore, is also popular among those who like to sunbathe in their birthday suits.

Should Playalinda be removed as an option, Schuttauf warned, nudists may overtake Apollo and end up going over the clothing optional line, causing some decidedly Floridian conflicts between them and their clothed counterparts.

Not everyone was interested in preserving the nude beach’s current status, however. Max West, a random man quoted by Space.com who claimed during the Zoom call that he plans to move to the area to photograph Starship launches, essentially suggested that the nudists suck it up.

“The turtles and the nudists will have to migrate,” West said, presumably alluding to disputes over whether SpaceX’s rocket debris pose a hazard to endangered sea turtles . “That’s the cost that you have to pay for this incredible stuff that’s happening.”

Unfortunately, it looks like that wannabe SpaceX photographer may end up getting his way.

Although the FAA hasn’t yet completed its environmental review for SpaceX’s request to move to Florida, and has yet to determine whether Musk’s company can meet both its financial and safety requirements to operate at the Kennedy Space Center, construction of a Starship tower has nevertheless been underway for more than a year — giving the impression that approval is a foregone conclusion.

More on SpaceX: SpaceX Suddenly Seems Pretty Terrified to Launch Starship After Long String of Super Expensive Explosions

Cameras have also slipped free in the vacuum of space. In 2007, astronaut Sunita Williams lost her digital camera during a spacewalk near the ISS solar arrays. Earlier, Apollo 11 astronaut Michael Collins misplaced a Hasselblad camera inside the cramped Columbia command module, jokingly reporting the incident to Neil Armstrong and Buzz Aldrin. Williams’s camera, like most lost items, eventually burned up on re-entry.