The Triassic–Jurassic boundary 200 million years ago marked the beginning of the dinosaurs’ dominance of the entire planet. Following the worst ever extinction event at the end of the Permian, 252 mya, dinosaurs started showing up in the fossil record around 245 mya but did not spread to all areas of the globe until the end of the Triassic. A new study in the Proceedings of the National Academy of Sciences (PNAS) posits one possible explanation for why the spread of dinosaurs was stymied. Sadly, this interesting but not conclusive report was immediately seized upon by climate alarmists as a cautionary tale about atmospheric CO2 levels. A news item in Science online labels modern levels “alarming” and implies that a fiery fate, like the one that held the dinosaurs at bay for so long ago, awaits us all.
Back at the beginning of Earth's existence there was a time known as the Hadean Eon—Hadean as in Hades, or hell. The history of the Hadean Earth (~4.0–4.5 billion years ago) is poorly understood because rocks from that time have not survived. The oldest known rocks are little older than ~3.8 billion years. A new paper in the journal Nature attempts to shed some new light on the least known part of Earth's distant past. Researchers have long speculated about the conditions on Earth in the first 500 million years after the planet's formation, some 4.5 billion years ago. The researchers report that, according to their model, the early Earth is likely to have been hit by up to four asteroids, each capable of snuffing out fledgling life and completely resurfacing the planet.
Supporters of the CO2 driven theory of anthropogenic global warming (CAGW) are in full panic mode. The continued hiatus in global temperature increase has led to a flurry of statements denying “the pause,” as climate scientists have named it. This new denialism even extends to international organizations like the WHO, that just recently claimed that global warming had not ceased, even though numerous organizations—including Britain’s Meteorological Office, NASA, and the IPCC—have admitted that it has. Among climate change true believers there is a scramble on to “find the missing heat” that would explain the pause. Strangely, among these practitioners of group think there is no consensus about the cause of the pause. At the same time, the IPCC is about to release its latest screed regarding climate change and the leaks have been flowing fast and furious, saying there is dissent in the land of consensus. This may well be the turning of the tide on the greatest scientific hoax in history.
A new Current Biology paper proposes that the accumulated output of dinosaur flatulence could have changed the global climate during the age of the dinosaurs. Insert dinosaur fart joke here. No, seriously, this is a real report in an actual scientific journal. It just happens to be on a subject that the news media could not resist blowing out of proportion on their best day. Given that much of the CO2 in Earth's atmosphere was emitted by some form of living creature this is a serious area for study by environmental scientists. So after giving the chattering media magpies some time to calm down, here is a more serious take on this heady topic.
Tyrannosaurs, the group of carnivorous dinosaurs that includes Tyrannosaurus rex and its closest relatives, are the most iconic and most studied of the dinosaurs. Made famous by movies, television shows and books, T. rex is the image most people think of when they hear the word dinosaur. The popular image of a tyrannosaur is that of a gigantic meat eater, like the one shown in Spielberg's Jurassic Park, but this was not always the case. T. rex was initially described 105 years ago by H. F. Osborn of the American Museum of Natural History. New fossil finds, including six new species during the past year alone, have shown tyrannosaurs to be a more diverse group that was first thought. A phylogeny that includes recently described species shows that tyrannosaurs originated by the Middle Jurassic but remained mostly small and ecologically marginal until the Late Cretaceous.
According to a recent paper, human actions may have caused Earth's climate to warm much earlier than previously expected. In an article to be published in Geophysical Research Letters, and widely reported in the media, around 15,000 years ago, early hunters were a major factor in driving mammoths to extinction. Supposedly, this die-off had the side effect of heating up the planet. This is an interesting conjecture, since a letter just published in Nature Geocience reaches the opposite conclusion regarding climate and the mammoths' decline. This mammoth confusion illustrates the uncertain and even contradictory evidence that abounds in climate science.
Recently this site posted an article about the extinction event 65.5 million years ago at the end of the Cretaceous period. That extinction coincided with a large asteroid impact at Chicxulub, Mexico, and occurred within the time of Deccan flood basalt volcanism in India. A new review article by 41 scientists, published in the March 5, 2010, edition of Science, was cited that summarized what science thinks it knows about the extinction. That article reinforced the single cause asteroid impact extinction scenario. Now, in an excellent example of how the scientific process works, and why scientific consensus is such a bogus term, the May 21 issue of Science has published a number of letters that take exception to the previous article's conclusions.
Although the story of the “Asteroid that killed the Dinosaurs” has become common knowledge for most people, there are still those scientists who back alternative causes of the end Cretaceous extinction even. Volcanoes, multiple meteor strikes and even widespread forest fires have been suggested as the cause of the dinosaurs' demise. The extinction event 65.5 million years ago did coincide with a large asteroid impact at Chicxulub, Mexico, and occurred within the time of Deccan flood basalt volcanism in India. A new review article by 41 scientists in the March 5 edition of Science runs down the list of what science thinks it knows about the extinction that set the stage for the age of mammals.
There have been a number of strange theories regarding the conditions deep within Earth's interior circulating around the internet. Claims that solar flares will cause nuclear reactions deep below our feet are perhaps the most ludicrous, but fairly easy to dismiss. More timely, perhaps, is the sudden conversion of global warming guru Al Gore into a geothermal energy booster. Evidently Gore thinks it's bad to drill for oil, but good to drill for heat. TV documentaries threaten mega-volcano eruptions and talk about mantle plumes underneath Hawaii, but just what does science tell us about our planet's interior?
There are a number of scientists who disbelive the theory that an asteroid impact killed the dinosaurs. They point to evidence that some species of sauropod may have survived the Chicxulub impact—widely hailed as the smoking gun in the dinosaur extinction—as proof that the event was simply not big enough to be a knockout blow. Now, according to Sankar Chatterjee of Texas Tech University, new information reinforces his claim that a much larger impact that he has named Shiva, actually did the dinosaurs in.