Today’s Rule Five theme: Eyes!
News and thoughts from the world of science: How The Burgess Shale Changed Our View of Evolution. Excerpt:
They are, in the opinion of no less an authority than the paleontologist Stephen Jay Gould, “the world’s most important animal fossils”—not Tyrannosaurus rex, not Lucy, but a collection of marine invertebrates mostly a few inches in size, dating from the very dawn of complex life on earth more than 500 million years ago. Their very names—Hallucigenia, Anomalocaris—testify to their strangeness. For decades they have fired the passions of researchers, fueling one of the great scientific controversies of the 20th century, a debate about the nature of life itself.
The origins of life on Earth are a mystery. But the Burgess Shale gives us an invaluable glimpse of what the origins of complex, multi-cellular life was like, and by our standards, it was passing strange. Take Hallucigenia, for example: a tube-legged, spiked anomaly, so named because it first appeared to paleontologists as something that might have been the product of a fever dream. And Anomolocaris was strange and frightening, a six foot long, armored predator with grasping, crushing mouthparts. When most people think of the past, they think of dinosaurs, an impressive group of animals in their own right that were dominant for over a hundred million years. But life before the dinosaurs was even odder than the dinosaurs themselves, and the examples found in the Burgess Shale reveal just how odd.
Speaking of life beginning anew: Should We Remake Mars in Earth’s Image? A story of terraforming; excerpt:
Mars is certainly a prize for colonization. The Red Planet has as much surface area as all of Earth’s continents combined, making it the focus of several grassroots space pioneering groups.
But this presents a conundrum. McKay asks if a biologically rich and diverse Mars is more valuable than largely preserving the beautiful, but seemingly dead, world we are exploring today.
Regardless of the tenants, the first task at hand is to change the Martian atmosphere to make the Red Planet a warmer and wetter world. Mars’ large flood features indicate there is a lot of water locked in the planet; there was likely even an ocean 4 billion years ago. The world first needs to be thawed out.
Super greenhouse gasses — such as chlorofluorocarbons — could be introduced. This would warm the Red Planet and release frozen carbon dioxide for further warming. This would eventually allow for rivers and streams to again flow under a denser atmosphere. The Big Thaw would take a few centuries by McKay’s estimates.
Worth doing? Well, America can’t do it at the moment – as I grow weary of pointing out, we’re broke. But in a few more generations, things maybe different; and sooner or later, maybe in mere moments on a geological time scale, another K-T event will occur. Our only hope in that event may be human presence on another world.
Mars is the closest candidate.