Curio Cabinet

Well, at least you can’t accuse these legislators of being boring. Several states in the U.S. have introduced legislation to ban fabled “chemtrails.” This is a name used by those who believe that the white, cloud-like lines left by airplanes contain deadly chemicals. The true nature of these streaks in the sky is not nearly that insidious, but they’re not completely harmless either.
 
The latest state to hop on the anti-chemtrail bandwagon is Louisiana, where a state legislator introduced a bill to outlaw the lines left in the wake of airplanes. A decades-old conspiracy theory holds that these are actually the result of a shadowy effort to disperse harmful chemicals to the general populace, but the proper term for them is “contrails,” short for condensation trails. Contrails generally form at altitudes between 32,000 and 42,000 feet due to the water vapor released from jet engines. At those altitudes, the hot water vapor cools rapidly after exiting the engine and condenses, leaving visible streaks in the sky. Of course, the conditions for this to occur have to be just right, or else the sky would be covered in an endless criss-crossing of airplane flightpaths. Aside from the altitude of the plane, the air has to be cold and humid enough for the contrails to form.
 
While contrails aren’t the product of nefarious intentions, that doesn’t mean that they’re beyond reproach. According to some studies, contrails might actually be contributing to global warming in an unexpected way by trapping excess heat in the atmosphere, especially if they form at night or last until nighttime. Ironically, efforts to reduce carbon emissions and save money might be making it worse. Modern airliners are designed to fly at altitudes of 38,000 feet to save on fuel by reducing drag in the thinner atmosphere, and while that certainly saves on fuel, it means that contrails are much more likely to form. The warming effect of contrails is so pronounced that they may be contributing more to atmospheric warming than the carbon emissions from the engines themselves. It’s a matter worth looking into for legislators, but they might want to familiarize themselves with the science around contrails first.

 
[Image description: A white plane with four contrails against a blue sky.] Credit & copyright: Adrian Pingstone (Arpingstone), Wikimedia Commons. The copyright holder of this work has released it into the public domain. This applies worldwide.

It’s the comeback of the century. The European beaver has made its triumphant return to Portugal for the first time in centuries, and it’s not the only place where the endangered builder is reclaiming its old range. Like its counterpart in North America, the European beaver is a keystone species, reshaping its environment by building dams in waterways and digging channels to direct the flow of water. Yet for all its mighty endeavors, the beaver was, for centuries, at the mercy of a greater power: human hunters. The beavers were hunted to near extinction in most of Europe for their meat, fur and castoreum, an aromatic substance that comes from internal sacs near the base of beavers’ tails. Beavers were even eaten during Lent after the Catholic Church classified the mammals as fish.
 
Beavers had a lot going against them when it came to their relationship with humans. Their fur happens to be ideal for making felt, and has been considered a valuable commodity for centuries. Although castoreum has a distinctly unpleasant odor in its raw form (beavers mix it with their urine to mark their territory), it can be processed into an effective fixative agent to be used in the production of perfumes. Thus, the beavers were trapped and hunted until they became extinct in many European locales, including Portugal, where they were last seen around the end of the 15th century. Then, over 500 years later in 2023, one of the beavers was sighted less than 500 feet from the border, giving hope to conservationists. Indeed, the presence of European beavers in Portugal has been confirmed now, with telltale signs like dams and gnawing marks on trees. It’s a long overdue arrival for Portugal, and it’s also the result of a century and a half of conservation efforts around Europe. While their numbers are still much lower than they once were, they are now found in most countries on the continent, and conservation efforts continue to help bring back the creature that once helped shape the very land. It’s time for these endangered engineers to get back to being busy beavers.

 
[Image description: A close-up photo of a beaver with wet fur.] Credit & copyright: National Park Service photo, Asset ID: d34648d9-10ec-44bb-bfce-9d4c2b20ee18. Public domain:Full Granting Rights.

They may be small, but they’re a big deal. Scientists at the Rosenstiel School of Marine, Atmospheric, and Earth Science have published a study in the journal Nature npj Viruses, detailing a slew of newly-discovered giant viruses that shape ocean life. While the ocean is vast and home to some of Earth’s largest creatures, the base of the food web still consists of its smallest denizens, including algae, amoeba, and flagellates (microscopic organisms defined by their single, whip-like tail that is used for movement). These organisms are greatly affected by giant viruses, which, as their name implies, are much larger than most viruses, with some even being larger than bacteria. Such viruses can cause havoc in the delicate balance of the ocean’s food web. Among other things, they can cause algal blooms, which can be directly harmful to animal and human health.
 
As significant as their ecological role is, giant viruses were poorly understood until recently, and little was known about their genome. To learn more, the researchers pored over existing marine metagenomic datasets and were able to identify 230 novel giant viruses, along with 530 new proteins. Some of these proteins were found to be linked to the viruses’ ability to manipulate the process of photosynthesis in their hosts, possibly explaining how they lead to algal blooms. In fact, figuring out how to deal with algal blooms was one of the motivations for the research. One of the study’s co-authors, Mohammad Moniruzzaman, explained, "By better understanding the diversity and role of giant viruses in the ocean and how they interact with algae and other ocean microbes, we can predict and possibly manage harmful algal blooms, which are human health hazards in Florida as well as all over the world.” Even some of Earth’s biggest problems are caused by small things.

[Image description: A digital illustration of green viruses against a blue background.] Credit & copyright: Author-created illustration. Public Domain.
 

These dinosaurs might have been impressive to look at, but their table manners were awful. While most animals have to chew their food thoroughly, it seems that wasn’t the case for sauropods, some of the largest dinosaurs ever to walk the Earth. Based on a recently discovered fossil, scientists now believe that sauropods hardly chewed their food at all.
 
Sauropods were members of Sauropoda, a clade of enormous, long-necked, vegetarian dinosaurs. Yet, for a long time, scientists didn’t know many specifics about sauropod diets. Paleontologists made the assumption that they ate plants based on two factors: they had flat teeth, which are good for processing plant matter, and sauropods were huge, meaning that there was no feasible way for them to have depended on anything other than plants, much like large herbivores today. Besides, their gigantic bodies, long necks, and long tails would have made them clumsy hunters. Now, not only do we have confirmation that sauropods ate plants, we know quite a bit about how they did it.
 
Researchers discovered a cololite—fossilized intestinal contents—that belonged to Diamantinasaurus matildae, a species of sauropod that lived around 100 million years ago. By performing a CT scan on the cololite, they found that the remains were composed entirely of plant matter. The leaves of the fern-like plant were largely intact, suggesting that the sauropod barely chewed them before swallowing. This means that sauropods were probably bulk feeders, ingesting as much plant matter as possible and relying on the natural fermentation process inside their digestive systems to break down their food. It’s a more extreme version of what many herbivores do today. Cows and other ruminants rely on fermentation to digest their food, and they also spend much of their time ruminating, which means they regurgitate their food to chew it again. You really needed a strong stomach to live in the Cretaceous period.

 
[Image description: A black-and-white illustration of a long-necked sauropod dinosaur.] Credit & copyright: Pearson Scott Foresman, Wikimedia Commons. This work has been released into the public domain by its author, Pearson Scott Foresman. This applies worldwide.

These wild equines have got a bit of a mean streak, plus a whole lot of stripes! The rescue of an escaped pet zebra in Tennessee has recently gone viral after the animal was airlifted to safety, but very few people will ever own a zebra. That might seem odd, given that their close cousins, horses, are some of humanity’s most prized domesticated animals. There are plenty of good reasons why zebras have never been domesticated, though, and why you’ll (hopefully) never see a person riding one.
 
Zebras are part of the genus Equus, along with horses and wild asses. These three groups represent the only living members of the family Equidae, and zebras are the only ones that have never been domesticated by humans. There are three species of zebras, and all of them live in grasslands, shrublands, and savannahs across eastern and southern Africa. There, they live in herds of up to 20 individuals, eating grasses and small, shrubby plants. Their beautiful black-and-white stripes make them stand out to human eyes, but they also break up their individual silhouettes, so that predators have a harder time pinpointing a single zebra. That’s important, since zebras have to survive amongst some of the most fearsome predators on the planet, including lions, hyenas, crocodiles, and wild dogs, among others. When confronted by predators, zebras will group close together to deter them. When that isn’t enough, however, zebras can and will fight, lashing out with powerful kicks and bites.
 
Unfortunately for humans, the behavioral adaptations that make zebras so perfectly suited for their African home are exactly the ones that make them impossible to domesticate. Zebras are aggressive enough to fend off lions, so would-be-zebra-riders don’t stand much of a chance. Zebras have a strong “ducking” instinct, which helps them protect their throats from predators in the wild. In a domesticated setting, it means that zebras are all but impossible to lasso or leash, and that they struggle against bridles. Zebras also don’t have a hierarchical herd structure, like wild horses do. This means that there are no leaders in wild zebra herds, which would make it pretty difficult for a zebra to accept a human as its leader. All in all, while zebras might look a bit like horses, they’re really a different stripe of creature entirely.

 
[Image description: A zebra walking through grass and brush.] Credit & copyright: Alvinategyeka, Wikimedia Commons. This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.