ريتشارد دوكنز's Blog, page 666
October 13, 2015
#askapaleo: National Fossil Day Q&A Tomorrow!
In honor of National Fossil Day (yep, it’s a thing), There's going to be a live twitter Q&A tomorrow, October 14, 2015, 2–3 p.m. EST* with me and a couple all-star paleos**:
Evolutionary anthropologist, fossil maven, & science writer @paleophile
Science writer, author, & omg! he consulted on Jurassic World: @Laelaps
Me. Paleobiologist, science writer, & lover of xenarthrans: @keeps3
Bring your questions! Bring your photos of unidentified fossils! And join us!
#askapaleo
*That’s 1–2 p.m. CST, 12–1 p.m. MST, and 11–12 a.m. PST. Can’t tell you how often I mess up time zones.
**We might have another fabulous paleo or two joining the roster... keep your phalanges crossed!
Newly discovered mammal species survived dinosaur extinction
Steve Brusatte/University of Edinburgh
By Victoria Gill
Scientists have discovered a species of ancient mammal that survived the event that led to the extinction of the dinosaurs.
The remains of this large, rodent-like creature give clues about how mammals “took over” when dinosaurs died out.
Kimbetopsalis simmonsae, as the newly discovered species has been named, was a plant-eating creature that resembled a beaver.
Dr Stephen Brusatte from the University of Edinburgh, lead researcher on the study, explained how a student on his team called Carissa Raymond found the fossil while prospecting at a site in New Mexico, US.
“We realised pretty quickly that this was a totally new type of mammal that no-one has seen before,” he told BBC News.
The researchers noticed in particular the animal’s teeth, which were specialised for plant-chewing, with complicated rows of cusps at the back and incisors at the front for gnawing.
They named the species after Kimbeto Wash, the area in the New Mexico badlands where it was found.
“The other part of the name – psalis – means ‘cutting shears’ and is in reference to [the] blade-like teeth,” Dr Brusatte explained.
Read the full article by clicking the name of the source below.
Ben Carson’s Scientific Ignorance
BILL PUGLIANO / GETTY
By Lawrence M. Krauss
For a man with an impressive educational C.V., Ben Carson makes a lot of intellectual missteps. In his September 16th debate performance, he displayed a profound lack of foreign-policy knowledge; last Sunday, when he said, on “Meet the Press,” that he “would not advocate that we put a Muslim in charge of this nation,” he may have seriously crippled his campaign. Still, there’s one area in which Carson’s credentials have seemed unimpeachable. Many people assume that, as a successful surgeon, he has a solid knowledge of technical, medical, and scientific issues.
With the wide release of video from a speech that Carson made to his fellow Seventh-Day Adventists in 2012, however, it’s becoming clear that there are significant gaps. In the speech, he made statements on subjects ranging from evolution to the Big Bang that suggest he never learned or chooses to ignore basic, well-tested scientific concepts. In attempting to refute the Big Bang, for example—which he characterized as a “ridiculous” idea—Carson said:
You have all these highfalutin scientists, and they’re saying that there was this gigantic explosion and everything came into perfect order. Now, these are the same scientists who go around touting the second law of thermodynamics, which is entropy, which says that things move toward a state of disorganization. So, now you’re going to have this big explosion, and everything becomes perfectly organized. When you ask them about it, they say, “Well we can explain this based on probability theory, because if there’s enough big explosions, over a long enough period of time, billions and billions of years, one of them will be the perfect explosion”…. What you’re telling me is, if I blow a hurricane through a junkyard enough times, over billions and billions of years, eventually, after one of those hurricanes, there will be a 747 fully loaded and ready to fly.
He continued, “It’s even more ridiculous than that, because our solar system, not to mention the universe outside of that, is extraordinarily well organized, to the point where we can predict seventy years away when a comet is coming. Now, [for] that type of organization to just come out of an explosion? I mean, you want to talk about fairy tales, that is amazing.” Finally, he argued that the observed motion of the planets in our solar system would be impossible if there had been a Big Bang.
Read the full article by clicking the name of the source below.
October 12, 2015
New AIDS Vaccine To Undergo Human Trials For First Time
Photo credit:
Sean Locke Photography/Shutterstock.
Dr Robert Gallo is a name you’ve probably never heard of, but he’s the biomedical researcher who led the team responsible for unmasking the cause of AIDS (acquired immune deficiency syndrome). In 1984, he was catapulted to world fame for discovering that the human immunodeficiency virus (HIV) was the malevolent infectious force behind one of the most debilitating epidemics in human history. HIV is, to date, essentially incurable. However, over 30 years on from the monumental discovery, Dr Gallo still hasn’t stopped his scientific crusade to combat this virus.
Groundbreaking Surgery Restores Hand And Arm Movement In Quadriplegics
Photo credit:
S_L/Shutterstock
It is quite the understatement to say that quadriplegia – the partial or total loss of function of a person’s limbs and torso – is a life-changing disability. Often caused by a severe spinal cord injury, many patients remain unable to regain any use of their limbs for the rest of their lives. Now, a pioneering new study at the Washington University School of Medicine in St.
River Dolphin Sonar Is Well-Suited For Life In The Busy Amazon
Photo credit:
guentermanaus/shutterstock
The echolocation clicks of toothy whales and dolphins typically encounter few obstacles at sea. Amazon river dolphins, on the other hand, live in shallow channels and flooded forests alongside dense vegetation – confined environments where sonar operations might result in high levels of clutter and reverberation. According to new findings published in the Journal of Experimental Biology, these dolphins rely on a high-frequency, short-range biosonar.
What a Teacher Learned in Grand Canyon
Scott Hatfield was one of NCSE’s Grand Canyon Teacher Scholarship winners. He teaches biology at Bullard High School, in Fresno, California. Teachers can apply for a scholarship on next year's trip, and you can donate to the scholarship fund or sign up for the trip now.
Scott Hatfield's photo of our campsite at Fern Glen Canyon
Crack. A short, sharp sound like a gunshot echoed off the walls around me, and in a moment my world changed—again.
Rain had come and gone for days in the Grand Canyon, but as I whipped my head toward the cliff behind me, I somehow knew instantly that the clap of sound was not thunder. Overnight, the cloudy skies and thunderstorms of the previous day had given way to startlingly clear blue skies. This was something else. Squinting in the morning sun, I saw a pale yellow plume above, with something heavier glinting in its midst. A downpour, not of rain, but rock.
I ran.
Cobbles and pebbles whistled as they flew by, and a fist-sized shard bounced off the water bucket I was hauling, gashing my thigh. Amid a drum solo of impacts booming and crackling, some deeper than others, I heard cries of alarm from every direction. As I reached the river, the roaring was replaced by a hissing sound, rising above all else and fading into nothing: the sand settling back to the beach after being kicked up by the rockfall.
And just like that, it was over: perhaps ten seconds at most of adrenaline for our party, but a moment that none of us would ever forget. It was a reminder that Science really is an adventure, a process of exploration and discovery that, if done right, challenges our expectations and assumptions about what we can know, what we can do, and what we can understand.
As a classroom teacher, I had leapt at the opportunity for adventure provided by NCSE’s new Grand Canyon Teacher Scholarship. Any lover of nature might relish an all-expenses-paid rafting trip down the Colorado River for the sheer physical thrill of the experience, but voyaging with NCSE meant that I would also receive expert lessons in natural history in an unforgettable setting.
I had known all along that the erosive forces that shaped the Canyon operated on what John McPhee has eloquently termed “Deep Time.” I knew that these forces worked in the same manner in the past as in the present, and were thus called uniformitarian processes: wind, water, and ice reducing and transporting the varied layers of rock over hundreds of miles and millions of years, pebble by pebble, grain by grain. But only living on the river really let me understand these dynamic processes.
Weather within the canyon takes on a kaleidoscopic aspect. At one bend, far from white water, you are baked in light bouncing off the rock walls, gently drifting inside the most picturesque solar oven imaginable. Yet within minutes, you are not only wrapped in shadow, but pelted by rain: sometimes drizzling, sometimes pouring. A slight shift in the wind can draw cold air out of shaded sidecanyons, or warm air from the desert above. On the river, the “layered look” is not a question of fashion sense, but a strategy to adapt to the elements: pull this hood down, peel this top off, change with the changes.
Beyond the vagaries of wind, sun, and shower, the river itself is flux personified. Heraclitus observed that you can’t step into the same river twice, even without the benefit of having rafted the Colorado. Even he would have been amazed, I think, at how the river changes as you ride down it: drifting by calm coves, bouncing through sprightly riffles, and pounding through crushing rapids where it feels like you’re being showered by the world’s largest bottle of Yoo-Hoo. So, the upshot of all this is that while you are pondering geological time on the river, you are pummeled by the present: amid the physical adventure, there is an intellectual voyage of discovery. From that vantage point, ideas and feelings coalesce in a way that is difficult to explain, but which now seems inseparable.
As I pondered the sum of uniformitarian processes at work carving the Canyon, voyaging through this wilderness reminded me that these processes reflect the accumulation of many individual events. Some, like the individual grains of silt moving through the rapids, are nearly invisible to the rafter; others, like a campsite rockfall, are dramatic and unforgettable to those that experienced them. Yet the vast majority of such happenings, past and present, innocuous or spectacular, will leave no mark for future voyagers; they will instead be destroyed by the “conveyor belt” of erosion, transport, and deposition. The sobering truth is that uniformitarian processes in and of themselves tend to generate and multiply mystery, rather than enlightenment, about the history of the Earth.
“Flood geologists” committed to a literal reading of Genesis attempt to exploit this situation. They rush to fill the lacunae of our understanding of the Canyon with what they imagine their faith compels them to affirm: a young Earth, and a worldwide Flood, a catastrophe of (literally) Biblical proportions. How ironic, then, that what ultimately confounds their efforts is what the Canyon reveals next: not one, but a succession of real catastrophes written in the rocks.
This happens because the “conveyor belt” of the Colorado River is also an “elevator,” whose attendant repeatedly intones, “Going down.” The river bends back and forth in every conceivable direction: here north, there south, and so forth. But regardless of what the compass says at any given moment, the overall trend is one of descent: with each mile on the river, voyagers find themselves further from the rim above them, and bracketed by rock of ever-increasing age. In a very real sense, the Canyon is a time machine.
Hatfield's trilobites, in Bright Angel Shale
Over the years I have amassed a fair collection of fossils for teaching purposes, many from the American Southwest. A particularly useful piece from Utah is a slab of black shale containing dozens of trilobites (Eltrathia kingii). As I explain to my students, this is a very common fossil in rocks of Cambrian age, such as the Canyon’s Bright Angel Shale. The many casts and impressions on this single rock no doubt reflect a rapid burial, an underwater landslide that entombed the many arthropods all at once.
Ironically, a deposit of the trilobite-containing Bright Angel Shale can be found at the very campsite where I and my river companions were menaced by rockfall. The afternoon before, I had found trace fossils, burrows and castings of creatures buried a half billion years ago, in the talus of rock at the base of the cliff—the very same cliff that, the next morning, would shoot projectiles of much younger age at our expedition! Thinking about it now, I have to smile: I can’t help but indulge the improbable whimsy that I just avoided burial and fossilization myself.
More seriously, I have to admit that contemplating extinction is sobering, and especially so for science educators today, due to our familiarity with the processes that imperil biological diversity: habitat destruction, invasive species, climate change. It’s vital that our students learn about these threats to their inheritance, the world that we share with the rest of life on Earth.
Yet the stark truth is that a real understanding of these processes can only be gained by acknowledging the scope of geological time, and the nature of biological evolution. Sadly, acceptance of this established science is still far from universal: teaching that the Earth is very old, and that life evolves remains controversial in many quarters, for reasons that have nothing to do with evidence.
That is why I am so grateful for the continued role of NCSE in educating the public, providing resources for the classroom and defending the teaching of evolution and climate change. As I hope my essay here makes clear, NCSE’s Grand Canyon Teacher Scholars program gave me opportunities and experiences that I never would’ve achieved on my own, and I would make the voyage again in a heartbeat. All of my fellow voyagers helped make this the trip of a lifetime, but I have to give a special tip of the rapid-soaked hat to NCSE staffers Josh Rosenau and Steven Newton for their leadership, generosity, and encouragement.
Finally, I don’t think I can do better summing up my feelings than by quoting Edwin Hubble:
Equipped with his five senses, man explores the universe around him, and calls the adventure—Science.
Answer Monday
Here’s a look at our specimen from last Friday with scale:
This fossil was collected from the Niobrara of Kansas. This wonderful American fossil site was first explored in the 1870s, and has yielded many excellent and dramatic vertebrate specimens: everything from mosasaurs to pterosaurs. This particular specimen is the humerus of a Pteranodon, species unknown.
I don’t know about you, but when I was a kid I loved pteranodons, though like most kids who grew up in the 80s I knew them as pterodactyls. Imagine my chagrin when my three-year-old corrected my nomenclature, thanks to his frequent viewing of PBS’s Dinosaur Train. The shame! However, I did my research (and remembered Stephanie’s blog which discussed this), so I know that pteranodons are not really dinosaurs. Unsurprisingly, my son violently disagrees with me on this point.
Regardless of this dispute, we are in unanimous agreement in my household that these flying prehistoric beasts are awesome. Some of the species that lived in what became the United States were huge, with wingspans up and sometimes even exceeding to six meters. Despite being gigantic and potentially terrifying, fossil evidence indicates that they mostly ate fish, as were abundantly found in the great inland seas that used to lie upon much of the Great Plains. It seems likely that these animals could dive like modern fishing seabirds, and that they flew in a manner similar to the modern albatross: with a lot of dynamic soaring, appearing to glide majestically while using as little energy as possible. Interestingly, most researchers now agree that these animals were quadrupedal when they walked around on the ground, which frankly would be a little creepy-looking.
Many of the fossils from these creatures are found slightly crushed, perhaps because, like other flying creatures, they had pretty delicate bones. However, quite a large number of fossils have been found, over a thousand, which include several articulated specimens as well as skulls. It used to be believed that there were more species of pteronodons than we currently think existed. Why? Because new research suggests that these animals had considerable sexual dimorphism, so it’s likely that individuals once classified separate species were actually males and females of the same species. Researchers now believe that females, which were much smaller, outnumbered males at about a 2:1 ratio, which could indicate that they lived along the shore in large colonies with polygamous males in a manner somewhat similar to modern sea lions.
Dinosaur Train might have the fish and the name right, but I don’t think I’ll burst my kids bubble quite yet regarding the species’ likely family structure.
The winner this week? Frankly, I was impressed at the detail and evidence laid out in many of your proposed answers, but the only person who got it right was Gary! Congratulations, and thanks for playing! If you have a fossil you want to share, send your pictures to me at schoerning at ncse.com.
AI machine achieves IQ test score of young child
Public Domain
By Nancy Owano
Some people might find it enough reason to worry; others, enough reason to be upbeat about what we can achieve in computer science; all await the next chapters in artificial intelligence to see what more a machine can do to mimic human intelligence. We already saw what machines can do in arithmetic, chess and pattern recognition.
MIT Technology Review poses the bigger question: to what extent do these capabilities add up to the equivalent of human intelligence? Shedding some light on AI and humans, a team went ahead to subject an AI system to a standard IQ test given to humans.
Their paper describing their findings has been posted on arXiv. The team is from the University of Illinois at Chicago and an AI research group in Hungary. The AI system which they used is ConceptNet, an open-source project run by the MIT Common Sense Computing Initiative.
Results: It scored a WPPSI-III VIQ that is average for a four-year-old child, but below average for 5 to 7 year-olds
Read the full article by clicking the name of the source below.
Smoking, heavy alcohol use are associated with epigenetic signs of aging
© Frank Täubel / Fotolia
By American Society of Human Genetics
Cigarette smoking and heavy alcohol use cause epigenetic changes to DNA that reflect accelerated biological aging in distinct, measurable ways, according to research presented at the American Society of Human Genetics (ASHG) 2015 Annual Meeting in Baltimore.
Using data from the publicly available Gene Expression Omnibus, Robert A. Philibert, MD, PhD and colleagues at the University of Iowa and other institutions analyzed patterns of DNA methylation, a molecular modification to DNA that affects when and how strongly a gene is expressed. Prior research had shown that methylation patterns change in predictable ways as people age, as well as in response to environmental exposures, such as cigarette smoke and alcohol. In these earlier studies, Dr. Philibert’s laboratory identified two specific locations in the genome, base pairs cg05575921 on the AHRR gene and cg23193759 on chromosome 10, at which methylation levels were highly associated with smoking and alcohol consumption, respectively.
In fact, they showed, DNA methylation levels at these two locations was a better measure of substance use than people’s self-reported estimates. Thus, in this follow-up study, Meeshanthini Dogan, MS, and Dr. Philibert used methylation levels as a proxy for tobacco and alcohol consumption. They estimated each person’s biological age using a previously validated epigenetic “clock” based on methylation levels at 71 locations in the genome, as measured by the widely used Infinium HumanMethylation450 BeadChip. Then, they calculated the difference between biological age and chronological age, and assessed the relationship between tobacco and alcohol use and premature aging.
Read the full article by clicking the name of the source below.
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