I’ll just say it. Contact with aliens? I don’t think it’s gonna happen.
I mean ever. And I don’t even think it’ll be our fault. Cultures across the globe could join together in common humanity, throw all nuclear weapons in the waste bin, and pour all our efforts into a singular, courageous, global effort to travel through space and find an alien civilization. But it won’t work, because some things are just impossible. Space is just too big. The distance between star systems is just too far. The speed of light is too unbreakable. The fuel for energy it would take to get through space is just too much. And finally, our biology is too connected to gravity — not to mention air, warmth and all the other things you don’t find much of in interstellar space.
All these earth-like exoplanets we keep finding offer at best the teeniest, tiniest sliver of hope. So they probably have liquid water? Cool. But we don’t even know yet if any of those worlds have, say, a magnetosphere — yet another wonderful thing that helps make life possible on Earth. It’s perfectly reasonable to wonder if Earth-like worlds with magnetospheres are kind of rare. After all, Venus and Mars don’t have one.
I am one of those people who gets emotionally attached to certain science facts that I learned in childhood. Sometimes I have a hard time when new findings update my ‘facts.’ For instance, despite assurances from the scientific community that Pluto wasn’t going to fall out of the sky or anything, I was still inexplicably sad when it lost its status as a planet. I even bought a ‘Pluto: revolve in peace’ shot glass.
Dinosaur facts are, for me, even more emotionally charged. I actually cried when I learned that Brontosaurus, my very favorite dinosaur, never really existed at all (I was four years old). The creature named Brontosaurus had already been discovered as some other uncool thing called an ‘Apatosaurus.’ Apatosaurus means ‘deceptive lizard.’ How apt. How true. For surely it deceived us all.
But last week I learned that at least part of my childhood dinosaur paradigm has been upheld! For the past 100 years, some scientists have painted Tyrannosaurus Rex, majestic king of eviscerating other dinosaurs, as a slow and clumsy creature that couldn’t hunt and merely scavenged. But a recent discovery might just put the scavenger idea to rest.
In the Proceedings of the National Academy of Sciences, University of Kansas paleontologist David Burnham and co-authors describe a fossil from a duck-billed dinosaur called a Hadrosaur. Something strange was stuck between two of its tail bones. After they scanned it with a medical device, they found out it was a tooth—a Tyrannosaurus tooth.
Of course, plenty of tooth marks on dinosaur bones show that T. rex ate other dinosaurs. But that doesn’t prove that T. rex actually killed his dinner. Perhaps, as the scavenger-boosters suggest, the T. rex’s sizeable olfactory lobes helped him sniff out and munch pungent dino carcasses. Many scavengers, including vultures, have large olfactory lobes.
But this fossil was different, and very special. The Hadrosaur’s bone had fused and grown around the tooth, meaning that the Hadrosaur had survived the attack with a T. rex tooth lodged in its tail as a souvenir.
“It’s the bullet from the smoking gun,” Burnham says. “Here you have attempted murder, and here we are able to identify the perpetrator.”
Still, the fossil doesn’t prove that T. rex didn’t also scavenge. After all, many predators like lions and hyenas happily eat a convenient carcass. It’s likely that T. rex ate any meal it could, hunted or scavenged.
Paleontologists work to understand ancient ecosystems, and this discovery provides scientists with a more complete picture of the Cretaceous food chain and T. rex’s role in it. But a special fossil that offers a glimpse at a specific event or behavior lets us more accurately imagine a moment of time in a long-gone world.
I admit that, despite all that this fossil adds to our understanding of the Cretaceous ecosystem, I am personally most excited that it reveals Tyrannosaurus rex as the ferocious hunter I’d imagined when I was four, playing with my small plastic dinosaurs.
As Burnham says, “T. rex is the monster of our dreams.”
No complete rocks have survived to tell of the formative years following Earth’s formation some 4.56 billion years ago. The material that would have existed at that time has been broken apart by the power of wind and water. It has melted and metamorphosed under the immense pressure and heat deep within Earth’s interior. It has been recycled back on to the surface. It has existed at every stage of the rock cycle many, many times over.
Despite the thousands of millions of years Earth’s earliest material has encountered, tiny pieces of some of these rocks still exist. Small microscopic grains of a mineral, once part of rocks that would have witnessed Earth as it existed just a couple of hundred million years after its formation, survive to this day.
The oldest known terrestrial material is a single grain of a mineral called zircon which was found in the Jack Hills formation in western Australia. It is 4.4 billion years old. The grain itself was part of a rock composed of the broken and eroded bits of other ancient material that itself has been subject to billions of years of geologic reworking.
Zircon is an extremely rugged mineral made up of silicon and the obscure element zirconium. Its tenacity in the face of time and its ability to provide scientists with enough information to figure out the age when it was formed are among the many reasons it is exciting to geologists. Read the rest of this entry »
We’ve all heard about the dangers of non-native plants: they outcompete natives; they carpet forest floors and smother roadsides; they cost us billions of dollars a year in control efforts. They’ve colonized huge swaths of the mid-Atlantic, where I live; I’ve written about them on this very blog. But is it possible that some introduced plants could prove beneficial in their new environments?
That’s certainly what Ariel Lugo thinks. Lugo, the director of the US Forest Service’s International Institute of Tropical Forestry, has long promoted a more catholic attitude toward plants of diverse origin. I recently visited him at the University of Puerto Rico’s Agriculture Experimentation Station in San Juan, where his office sits among groves of eucalyptus and bamboo—both of which humans introduced to the island. According to Lugo, the immigrant vegetation reflects the welcoming Puerto Rican spirit. “Here, we don’t persecute trees,” he says. “The federal government is the only one that persecutes trees.”
As far as Lugo is concerned, any species that can help his island recover from past environmental devastation—near complete deforestation, large-scale cultivation of sugarcane and other crops—is welcome. In 1992 he published a paper comparing the understories of pine and mahogany plantations with those in regrowing native forests. Lugo found that similar numbers of species were growing in both places, and that many of the understory plants in the plantations were native. Moreover, he found the older plantations were starting to give way to native overstory trees. “The study challenges the conventional dogma…and underscores the dangers of generalizing about all tropical tree plantations or all natural tropical forests,” he wrote. According to science writer Emma Marris, it took Lugo almost a decade to get his paper accepted.
The best-laid plans of lab mice and science writers often go awry.
OK, that’s a tad hokey maybe. To the point: The Sieve began about a year-and-a-half ago as a way for students in the full-time science writing program at Johns Hopkins University to test the waters of blogging. It was a fun way to practice our writing, interact lightly with the rest of the science writing community on the Web, and learn what it’s like to obsess over pageviews and reshares. We even passed the blog on to the science writing class that came after us, and it seemed like it could become a long-lasting fixture of the program.
Then, to our bewilderment, the university closed the program this year. Many of us who graduated from the program had become attached to it. Ann Finkbeiner, who ran the program, is an amazing instructor who never failed to challenge our bad writing habits. Also, the classes were small: The number of grad students ranged from four to six, each class soldiering through one intense year of a ton of writing, workshopping, rewriting, more workshopping, and more rewriting. You would graduate with a feeling that this unique program that had only shaped a few careers in its 30-year history had become a piece of you. So its closure left much of us feeling dumbfounded, no matter the rationale.
On top of the dumbfounded feeling, there was another thing. Our poor little blog was bobbing along at the surface without its anchor. (I’ve used that metaphor maybe three times now in private emails. I guess once more can’t hurt.) What could we do with it? Well, we couldn’t save the Hopkins program. But we could save the blog. So a few of us, mostly relatively recent graduates of the program, have stepped in to do just that.
Really, the blog is only changing in one way. It remains what it was before in that it’s a place to tell stories about science. All that’s changed is that This Is Not A Drill. We’re science writers with a bit of experience under our belts, with jobs or freelance careers or both.
As we start off on the new phase, we’ll be making at least one new post every week. We’ll probably make some other changes along the way, perhaps a visual redesign (I’m an ex-newspaper guy and I think the current design reflects those slightly aged sensibilities. It’s probably due for something more fresh). Anything is possible. In the meantime, just as before, we have stories we want to tell, and here is where you can find them. In the coming weeks, you can look forward to posts from Gabriel Popkin, Alex Kasprak, Emily Mosher, me, Jay Thompson, Helen Thompson, Kelsey Calhoun and Rachel E. Gross.
(Image: Rama/Wikimedia Commons)