Ever since widespread consensus was reached last decade that a meteorite was at least partially responsible for the extinction of the dinosaurs (among other organisms) at the end of the Cretaceous, it's been en vogue to try to show that meteorite or comet collisions can be linked to all the major mass extinctions. I'm usually very skeptical of such studies, which are often highly speculative and smack more of self-promotion than of good science. That said, it's never worth shooting such hypotheses down without having first heard the evidence used to formulate them. With that in mind, I went to a talk last Friday given by two professors from the anthropology department here at Oregon. It was, in effect, a practice talk in advance of the official presentation of their findings this week at the Geological Society of America's meeting in Acapulco. The research group - which consists of 26 (!) members from representing many different fields - had come across several lines of evidence that seem to suggest that a small meteorite, or more likely a comet, smashed into Michigan 13,000 years ago. These lines of evidence included such things as an iridium spike and nannodiamonds, both of which are generally associated with some type of extraterrestrial impact. I was ready to be a skeptic, but I have to admit, their argument was very compelling. While the impact itself would have been relatively minor, the authors suggest that such an event in an area that was then covered by glaciers would shatter ice dams holding back massive glacial lakes, wreaking havoc on ocean circulation and, by extension, climate.
As anthropologists, the presenters I saw were most interested in how the impact might have affected North American paleoindian society. I was more interested in a topic they touched upon only briefly. For several years, one of the most contentious debates in paleontology has been the argument over whether humans are responsible for the extinction of large "Ice Age" mammals (megafauna). It's been a particularly vitriolic debate, with each side having its share of convincing arguments, bad science, and flat-out name-calling. This comet hypothesis will no doubt light an entirely new fire under a cauldron that's already been boiling for some time. As such, I have no doubt that the findings of this will be debated and subjected to several rigorous geological, anthropological, and paleontological test, and I for one look forward with great interest to seeing how well they hold up under scrutiny.
24 May 2007
Eugene is Oregon's Second City, and it likes to bill itself as the "World's Greatest City of the Arts and Outdoors" (whatever that means). It has an acclaimed symphony orchestra, beautiful parks, a major university, and in general is far more urban and cosmopolitan than a city its size should be. That said, it's still very much part of Oregon, and no matter where you go in this state, nature is never very far away. Case in point: when I came home from the university today, I looked out my kitchen window and saw the scene at left. Deer are hardly anything remarkable, but the seeing wild animals - fairly large ones, at that - in your backyard is always a novelty when you live in a city. Even more memorable was watching the many neighborhood cats try to stalk the deer (without much success, as you might imagine, though one did manage to get close enough to bat at a tail).
22 May 2007
A few weeks back, I posted to commemorate T.H. Huxley's birthday. This week, I want to acknowledge the birthday of another great Victorian, Sir Arthur Conan Doyle. Besides Charles Dickens, no author has ever been so adept at conjuring up images of Industrial Era Britain, from the foggy streets of London in its glory days, to the eerie tors of Dartmoor, to the fading elegance of a ducal mansion. Conan Doyle's gift for evocative description was most frequently put to use to enliven the adventures of his most famous creations, Dr. John H. Watson and Sherlock Holmes (The Sign of Four and The Hound of the Baskervilles, for example, each have settings that are every bit as compelling as the characters themselves). Conan Doyle was also a well-educated man with a keen understanding of science (though he lapsed into mysticism and quackery towards the end of his life - the Sherlock Holmes story The Creeping Man is a particularly embarrassing product of this stage). He wrote The Lost World, the first and still the best dinosaur novel out there; it's significantly more exciting, engaging, and creepy than any of Michael Crichton's efforts. Its plot is simple: a group of explorers find an isolated plateau in South America that preserves a primeval world of dinosaurs and ape-men. Tenuous as this segue may seem, Conan Doyle's writing has always appealed to me because it itself paints a picture of the lost world: the Victorian Era, a world which was unexplored enough and still rife enough with possibility to engender The Lost World but which was also coming to terms with its increasingly prevalent dark side so familiar to the world's greatest detective. I may never really understand why I have such a fascination with Industrial Britain, but I know that Conan Doyle's vivid depiction of it is largely responsible. And for that, I am eternally grateful.
20 May 2007
Today, the Discovery Channel has been airing the BBC series Planet Earth. I had heard about the series before, but I'd been skeptical: it couldn't really be as good as everyone claimed it was, could it? Turns out that yes, it is. Here's why:
- As the narrator is never tired of reminding you, the cinematography in the series is nothing short of stunning. There are gorgeous landscape shots (like a top-down view of Angel Falls and a flyby of a fog-shrouded coastal forest right here in the Northwest), close-ups catching animal behavior "in the act" (like macaques diving for food in Indonesia or the mating display of a bird of paradise), or - best of all - combinations of the two (the most spectacular example being a snow leopard hunt on a sheer cliff face in the Himalayas). The producers also do a great job of using slow-motion footage (of a great white shark leaping to catch a seal, for example) and stop-motion (to show a sunflower sea star chasing brittle stars across the California seafloor).
- Many nature documentaries focus on one individual or group. While this might make for a good story-line, it also opens the door for anthropomorphism and presents logistical problems (one documentary on baboons is notorious for having used five or six other individuals stand-ins for the "main character," of which they just didn't have enough footage). Planet Earth takes a much more holistic approach, with each episode focusing on an entire biome. While much of the documentary is still devoted to animals, other organisms get plenty if air time as well, as does the physical environment itself.
- The producers aren't afraid to show "nature, red in tooth an claw." It's always annoyed me that most documentaries will show only the appealing bits of the natural world, cutting away from footage hunts just before the kill, for example. Planet Earth, on the other hand, doesn't skimp on the carnage, whether it's a chimp cannibalizing an infant from another troop or a parasitic fungus erupting out of the head of an ant (in stop-motion, no less). It may be gruesome to some people's eyes, but a documentary that shows only those aspects of the natural world that they think viewers will want to see are, at best, telling only half the story.
- Many nature documentaries also like to drive home their conservation message with a sledgehammer. I'm as pro-conservation as the next guy, but finger-pointing and guilt-mongering are annoying at best, and more commonly are entirely counterproductive. Planet Earth most certainly has the same goal, but it is much more nuanced and subtle about it. One of the producers stated that the aim of the program was to show people that there are still places out there worth saving, and there can be no doubt that Planet Earth does so masterfully. It would take a truly hard-hearted person to watch this and not be moved on some level, and to paraphrase the old adage, there is no better way to inspire conservation efforts than to first inspire appreciation.
04 May 2007
Today is the 182nd birthday Thomas Henry Huxley, the man known as "Darwin's Bulldog" and one of my personal heroes. I've been taken to task a few times for my hero-worship, because it's certainly true that not everyone out there is a big T.H. Huxley fan. He was very much a product of his time and his culture (Victorian England), and almost any historical figure starts showing flaws when viewed from a modern perspective. So yes, he did have a running feud with the Salvation Army because he didn't like the idea of handouts to people who didn't work for them, but I would argue that any such non-PC idiosyncrasies are more than counterbalanced by the good he did. There are two things for which I particularly admire Huxley. First, every one of us out there who considers ourself to be a scientist owes the man an enormous debt of gratitude, because in many ways he was the first professional scientist. Pre-Victorian scientists were largely independently wealthy aristocrats and clergymen that indulged in "natural philosophy" as a hobby, while Huxley was a "common" Londoner who relied on science as a career. More importantly, he was famous as a teacher, educating a generation of students in the newly-emerging fields of biology and geology (and in the intersection of those two fields, paleontology). The second thing I admire about Huxley is his eloquence. There have been many great scientists, but many of them have been terrible at communicating their research to the rest of the world. To be able to explain one's ideas in a way that both instructs and engages is a very rare gift, and it was a skill that Huxley had in spades. He was able to take a commonplace object, such as a crayfish or a piece of chalk, and use use these as means of introducing much larger-scale topics; he was so good at this that his lectures were regularly packed to the gills not just by fellow scientists, but by the general public as well. I have read the transcripts of some of his lectures, as well as some of his essays, and even now, almost two centuries after the fact, they remain works of stunning rhetorical beauty. Of course, his golden tongue is best remembered for its defense of Darwin's then-new theory of evolution by natural selection. Huxley was far and away the most successful promoter, defender, and teacher of evolution of his time, and it is doubtful that natural selection would not have become recognized as the fundamental theory of biology as quickly as it did if not for his efforts. So, Happy Birthday, T.H. Huxley; here's hoping that there are a few more out there like you...