extinction

From ScienceDaily: A University of Adelaide study into New Zealand’s acanthisittid wrens has provided compelling evidence that, contrary to some suggestions, New Zealand was not completely submerged under the ocean around 21 to 25 million years ago. “Most surprisingly, we found that some of the wren species were only distantly related to each other, potentially sharing a common ancestor over 25 million years ago,” Dr Mitchell says. “Previously, researchers have suggested that New Zealand was completely submerged 21 to 25 million years ago, which implies that all of New Zealand’s unique plants and animals must have immigrated and diversified more recently than that time. … “But the ancient divergences we found among the wrens suggest that they have been resident Read More ›

Smarter than yer average animal. From ScienceDaily: The event, known as the end-Ediacaran extinction, took place 540 million years ago. The earliest life on Earth consisted of microbes — various types of single-celled organisms. These held sway for more than 3 billion years, when the first multicellular organisms evolved. The most successful of these were the Ediacarans, which spread around the globe about 600 million years ago. They were a largely immobile form of marine life shaped like discs and tubes, fronds and quilted mattresses. After 60 million years, evolution gave birth to another major innovation: metazoans, the first animals. Metazoans could move spontaneously and independently at least during some point in their life cycle and sustain themselves by eating other Read More ›

(Note: A previous version of this story was just rejected by Facebook for allegedly dangerous material. It is reposted here and went through at Facebook this time. Apologies for any inconvenience.  – News) Naturalism, like many religions, features an apocalypse. One prophecy is for wastage by a comet. From New Scientist: “Some say the deep microbial biosphere couldn’t survive because if you wipe out the surface ecosystem, sooner or later the nutrients they need will disappear,” says Ward. So if life here were extinguished, could it start again? “You could argue that it happened once, so it would likely happen again,” says David Kring at the Lunar and Planetary Institute in Houston, Texas. “But it’s difficult to say because strictly speaking, we Read More ›

After devastating extinction. From the Guardian: The discovery of a toothless animal with a short snout and a long tail that roamed the seas around 247 million years ago, suggests early marine reptiles evolved more rapidly than previously thought after the the most devastating mass extinction event the planet has ever experienced, scientists have revealed. Dubbed Sclerocormus parviceps, a name that nods to its rigid body and small skull, the ichthyosauriform was unearthed by fossil hunters in China. But its appearance has surprised researchers. Sclerocormus is lacking a host of features seen in closely related marine reptiles: many ichthyosaurs had a long snout, teeth and a tail with big fins – none of which are present in the new find. Read More ›

From ScienceDaily: The University of Illinois and University of Puerto Rico have completely sequenced the mitochondrial genome for the Hispaniolan solenodon, filling in the last major branch of placental mammals on the tree of life. The study, published in Mitochondrial DNA, confirmed that the venomous mammal diverged from all other living mammals 78 million years ago, long before an asteroid wiped out the dinosaurs. “It’s just impressive it’s survived this long,” said co-first author Adam Brandt, a postdoctoral researcher at Illinois. “It survived the asteroid; it survived human colonization and the rats and mice humans brought with them that wiped out the solenodon’s closest relatives.” That is why it is endangered now, researchers say. While the solenodon is venomous and Read More ›

Yeh, the End of All Thing IS at hand. File yer tax return first, okay? The government needs the money. Robinson Meyer at the Atlantic channels the best of science: Nuclear war. Climate change. Pandemics that kill tens of millions. These are the most viable threats to globally organized civilization. They’re the stuff of nightmares and blockbusters—but unlike sea monsters or zombie viruses, they’re real, part of the calculus that political leaders consider everyday. And according to a new report from the U.K.-based Global Challenges Foundation, they’re much more likely than we might think. In its annual report on “global catastrophic risk,” the nonprofit debuted a startling statistic: Across the span of their lives, the average American is more than five Read More ›

DNA proves it, say researchers. From ScienceDaily: New research examining the DNA of North American mammoths challenges the way we categorize a species. Several species of mammoth are thought to have roamed across the North American continent. The new study results show that while mammoths clearly evolved differences in their physical appearance to deal with different environments, it did not prohibit them from cross-breeding and producing healthy offspring. Paper. (public access) – Dan Fisher et al. Mammuthus Population Dynamics in Late Pleistocene North America: Divergence, Phylogeography and Introgression. Frontiers in Ecology and Evolution, April 2016 DOI: 10.3389/fevo.2016.00042 … A species can be defined as a group of similar animals that can successfully breed and produce fertile offspring. By using differences Read More ›

The dinosaurs, we are now told, were dying out before the asteroid hit. From Ed Yong at the Atlantic: Manabu Sakamoto from the University of Reading has shown that dinosaur species were going extinct faster than new ones were appearing, for at least 40 million years before the end of the Cretaceous. The dinosaur opera had already been going through a long diminuendo well before the asteroid ushered in its final coda. Many other researchers had looked at the fates of the dinosaurs before that infamous extinction event and suggested that they were already declining. But most of these studies had simply tabulated raw numbers of species from different blocks of time. This approach has problems: the rocks from certain Read More ›

The largest dinosaurs who ever lived became increasingly front-heavy over time: The team found that these linked trends in size, body shape and weight distribution did not end with the evolution of fully quadrupedal sauropods. In the Cretaceous period — the last of the three ages of the dinosaurs — many earlier sauropod groups dwindled. In their place, a new and extremely large type of sauropod known as titanosaurs evolved, including the truly massive Argentinosaurus and Dreadnoughtus, among the largest known animals ever to have lived. The team’s computer models suggest that in addition to their size, the titanosaurs evolved the most extreme ‘front heavy’ body shape of all sauropods, as a result of their extremely long necks. … Dr Read More ›

From ScienceDaily: Two hundred and fifty-two million years ago, a series of Siberian volcanoes erupted and sent the Earth into the greatest mass extinction of all time. As a result of this mass extinction, known as the Permo-Triassic Mass Extinction, billions of tons of carbon were propelled into the atmosphere, radically altering the Earth’s climate. Yet, some animals thrived in the aftermath and scientists now know why. In a new study published in Scientific Reports, a team of international paleontologists, including postdoctoral scholar Adam Huttenlocker of the Natural History Museum of Utah at the University of Utah, demonstrate that ancient mammal relatives known as therapsids were suited to the drastic climate change by having shorter life expectancies and would have Read More ›

From the New York Times, we learn: Ancestors of Modern Humans Interbred With Extinct Hominins, Study Finds The ancestors of modern humans interbred with Neanderthals and another extinct line of humans known as the Denisovans at least four times in the course of prehistory, according to an analysis of global genomes published Thursday in the journal Science. The interbreeding may have given modern humans genes that bolstered immunity to pathogens, the authors concluded. “This is yet another genetic nail in the coffin of our oversimplistic models of human evolution,” said Carles Lalueza-Fox, a research scientist at the Institute of Evolutionary Biology in Barcelona, Spain, who was not involved in the study. The new study expands on a series of findings Read More ›

Worrying on behalf of the Sixth Great Extinction, Patrick Monahan at Science: … That’s why Roy Plotnick, a paleontologist at the University of Illinois, Chicago, and lead author of the study, thinks about far-flung scenarios involving future paleontologists. “We really need to look at modern day extinctions as if they were in the fossil record already, in order to make a comparison,” he says. So he and his colleagues searched fossil databases for modern mammal species—both those threatened by extinction and those that aren’t—to see how many modern extinctions would be detectable by relying only on fossils. Humans have recorded fossils for just 9% of the world’s threatened modern mammal species, the team reports this month in Ecology Letters. Nonthreatened Read More ›

Recently, I was astonished when I came across an article titled, Are We in a ‘Sixth Great Extinction’? Maybe Not, by Ross Pomeroy, an editor of RealClearScience and a zoologist and conservation biologist by training. The author’s candor and intellectual honesty are refreshing: The notion that humans are erasing species off the face of the Earth at near unprecedented levels is a perennial story that has been blared in the media for more than two decades. In the year 2000, the United Nations’ Millennium Ecosystem Assessment estimated that species are going extinct 1,000 times faster than they naturally do, and that this rate could increase to 10,000 times. These rates translate to between 17,000 and 140,000 species going extinct each Read More ›

Depending on how we define species, extinction, as well as hybridization and evolution. From ScienceDaily: New research from UBC shows that when humans speed up the usually slow process of evolution by introducing new species, it can result in a lasting impact on the ecosystem. The phenomenon is known as reverse speciation and researchers witnessed it in Enos Lake on Vancouver Island where two similar species of threespine stickleback fish disappeared within three years.”When two similar species are in one environment, they often perform different ecological roles,” said Seth Rudman, a PhD student in zoology at UBC. “When they go extinct, it has strong consequences for the ecosystem.” Two species of endangered threespine stickleback fish lived in the lake. One Read More ›

Further to Intelligent design “horrifying” Because extinctions occur in the course of nature, philosopher and photographer Laszlo Bencze writes to say: The article quotes the letter writer as saying: The earth has experienced five mass extinctions. What kind of designer makes a system that periodically wipes out species for no apparent reason? Are these extinctions simply an “oops” moment on the part of the creator? This boils down to the statement, “No god I can conceive of would do such a thing,” with the emphasis on “I”. It never seems to enter the minds of the many people who make such statements that god might be completely other than the “I” making the statement. Any god who was limited to Read More ›