Fox News has a January 7 Science & Technology news story titled "Cataclysm that killed dinos still taking lives today." I can not believe this was published by a major news organization. Some excerpts from the news story...
"The tremendous volcanic eruption thought to be responsible for Earth's largest mass extinction — which killed more than 70 percent of plants and dinosaurs walking the planet 250 million years ago — is still taking lives today."
There was indeed a mass extinction 250 million years ago (Ma). It was called the Permian extinction since it marks the end of the Permian Period of the Paleozoic Era of geologic time and the start of the Triassic Period of the Mesozoic Era. This is a fundamental division in the geologic time scale (placed there because the fossils show this huge extinction event and a big change in the type of life present on Earth).
Problem is, there were no dinosaurs around at this time - none. A lot of people think that there was only one mass extinction in the past and it was the one which killed off the dinosaurs (this was the K-T extinction which occurred between the Cretaceous Period of the Mesozoic Era and the Tertiary Period of the Cenozoic Era - another fundamental break in the geologic time scale that occurred about 65 Ma). In reality, there have been numerous mass extinctions with the Permian one being the worst.
Bottom line... Prior to 250 Ma, there were only reptiles (no dinos). Permian mass extinction 250 Ma. Dinos evolve and rule earth for some 180 Ma. K-T extinction 65 Ma. No more dinos. Big difference.
By the way, the Permian extinction was even worse than the quote above makes it sound. The 70% estimate is only for terrestrial vertebrate species (not nonexistant dinosaurs). One group of terrestrial vertebrates greatly effected by this event were the therapsids - also known as mammal-like reptiles (reptiles which eventually evolved into the mammals). Well over 90% of marine species became extinct as well (think about that for a minute).
Now I can understand non-scientists (and my students) not knowing about the Permian extinction. But a journalist and an editor at a major national news organization writing for the Science & Technology section? I'm not one of those knee-jerk "Fox News sucks" people - hell, I think CNN and MSNBC suck too - but in this case, they do indeed look like morons.
Reminds me of our local newspaper. Once, when we offered a night telescope observation on my Campus open to the public and once when they reported on an event on Campus called Science Olympiad, they confused astronomy with astrology. When confronted with this, the editor basically said "Don't make such a big deal out of this, it was just a typo." No, sorry. Typing "astronony" is a typo. Typing "astrology" is ignorance. To a science person, saying "XX Community College is offering a night astrology observation on Friday" is a glaring error that just jumps off the page. Of course, the paper (like most in this country) carries a daily astrology column but barely ever covers astronomy (or any other science except health-related ones).
Next excerpt...
"Scientists investigating the high incidence of lung cancer in China's Xuan Wei County in Yunnan Province conclude that the problem lies with the coal residents use to heat their homes. That coal was formed by the same 250-million-year-old giant volcanic eruption — termed a supervolcano — that was responsible for the extinction of the dinosaurs. The high silica content of that coal is interacting with volatile organic matter in the soil to cause the unusually high rates of lung cancer."
Coal is not "formed" by volcanic eruptions. Coal is basically buried and compressed plant material. And don't get me started on the term "supervolcano" - it's an invention of science journalists and media-whoring geologists who want to be on TV.
The real story here is actually quite interesting. About 251-250 Ma, huge volumes of basaltic lava erupted in the area that's now Siberia and resulted in an area called the Siberian Traps (traps is derived from a word meaning "steps" because sheet-like lava flows often erode into step-like plateaus). These basalt sheets cover a few million square kilometers - a vast area of the landscape. During the extrusion of this lava, there were also associated pyroclastic eruptions of ash that reached the stratosphere and were spread around the world.
Some of this ash, composed of very fine particles of the mineral quartz (silica), settled into swamps and peat bogs in what's now China. This silica was buried with the plant material and it all formed into coal that's mined today. Chinese laborors burn this coal for fuel in their homes and it releases the silica back into the atmosphere where it's breathed in and seems to cause increased rates of lung cancer.
A neat story. One that Fox News totally screwed up. Wired magazine has a much better story - Chinese coal formed during earth's greatest extinction is deadly.
Friday, January 8, 2010
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