Saturday, August 05, 2006
It was a science fiction fantasy come true: Ten years ago this summer, NASA announced the discovery of life on Mars.
At a Washington, D.C., news conference, scientists showed magnified pictures of a four-pound Martian meteorite riddled with wormy blobs that looked like bacterial colonies. The researchers explained how they had pried numerous clues from the rock, all strongly supporting their contention that microscopic creatures once occupied its nooks and crannies.
It was arguably the space agency's most imagination-gripping moment since Apollo. Space buffs and NASA officials said that it just might be the scientific discovery of the century.
'If the results are verified,' the late Carl Sagan pronounced, 'it is a turning point in human history.'
Ten years later, the results have not been verified. Skeptics have found non-biological explanations for every piece of evidence that was presented on Aug. 6, 1996. And though they still vigorously defend their claim, the NASA scientists who advanced it now stand alone in their belief.
The great apes are the smartest of all non-human primates, with orangutans and chimpanzees consistently besting monkeys and lemurs on a variety of intelligence tests, Duke University Medical Center researchers have found.
It's clear that some species can and do develop enhanced abilities for solving particular problems," said Robert O. Deaner, Ph.D., who led the study as part of his doctoral dissertation. "But our results imply that natural selection may favor a general type of intelligence in some circumstances. We suspect that this was crucial in human evolution."
The study was published online August 1, 2006, in the journal Evolutionary Psychology (download here). Funding was provided by the medical center's Department of Biological Anthropology and Anatomy.
technorati tags: great+apes, primates, orangutans, chimpanzees, monkeys, lemurs, intelligence, duke+university, species, natural+selection, human, evolution, evolutionary, psychology, anthropology, anatomy
No secret handshake, no decoder rings or midnight rituals. Just a $200 cabin on a 12-acre island, plenty of brainpower, and a commitment to the flora and fauna of home.
The Washington Biologists' Field Club is celebrating 100 years of self-professed geekdom (six years late) this year, with a 150-page volume summarizing a century of counting every living thing on Plummers Island, the club's buggy, overgrown paradise a few steps into the Potomac, just downriver from the American Legion Bridge.
Established in 1901 as a weekend retreat, Plummers Island, called by the field club "the most thoroughly studied island in North America," today represents one of the most comprehensive, longest-running biological inventories in the country. [Washington Post]
Brian Alters is on the cover of the Summer 2006 issue of Humanist Perspectives, which devotes a full eleven pages to discussing the controversy that arose in the wake of the Social Sciences and Humanities Research Council of Canada's deciding not to fund Alters's research project to study the effects of the popularization of 'intelligent design' on Canadian students, teachers, parents, administrators, and policymakers.
Alters's proposal was rejected, according to a letter from SSHRC, in part because it failed to provide 'adequate justification for the assumption ... that the theory of evolution, and not intelligent-design theory, was correct.'
Philip Sadler, director of science education at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, quipped to Nature (August 4, 2006), 'If he was trying to answer the question as to whether all this popularization had had an impact, he just saved the government $40,000 ... He found the evidence without doing the study.'
Hundreds of scientists in Canada and abroad protested what seemed to be SSHRC's crediting 'intelligent design' with scientific legitimacy on a par with evolution's.
technorati tags: brian+alters, intelligent+design, humanist, perspectives, controversy, social+sciences, humanities, research, canada, council, theory, evolution, science, education, harvard, smithsonian, astrophysics, nature
Ahmedabad, August 4: One always wonders why members of a particular species become extinct at the same time across the globe. The answer to this puzzle has been explained in a paper (Abstract) authored by two Indian scientists and published by the American Institute of Physics, as well as British website, Physics Web.
Dr R E Amritkar of Physical Research Laboratory, Ahmedabad, and Dr Govindan Rangarajan of Indian Institute of Science, Bangalore, have explained the puzzle with the help of a theory called Special Spatial Synchronisation.
They say that separated communities of the species synchronise together before becoming extinct.
Amritkar and Rangarajan say in the paper that animal populations all over the world are likely to synchronise their numbers before dying out. This is why, in the Cretaceous Tertiary period, the last period of mass extinction, about 65 million years ago, dinosaurs of the same species died out at the same time.
Friday, August 04, 2006
Robyn William's heart sank this week when he listened to people from Toowoomba on the radio blithely rejecting the latest scientific evidence on the quality of recycled water in favour of the myths.
It was as if science was just another choice of product on a supermarket shelf they could ignore at will, says the ABC (Australian Broadcasting Corporation) science broadcaster. 'People simply say, 'I don't want to know that. It's inconvenient'.'
The prevalence of this attitude has been playing on Williams's mind as he ponders the way the intelligent design movement - creationism's 'belligerent teenage cousin' - has sprung up 'like a boil on a bum'. One of its hallmarks, he says, is the arrogant dismissal of carefully weighed scientific evidence.
Until recently Williams had thought it unwise to give any more publicity to intelligent design - the notion that life is too complex to have evolved without some assistance from an intelligent designer, whom many adherents believe to be God.
But its well-resourced backing in the US, from the President, George Bush, down, and its spread here - it is taught in science classes in about 100 schools, he estimates - has finally forced him into print.
He pulls no punches. Intelligent design is a politically sinister movement, a form of terrorism focused on public education, he argues in a new book, Unintelligent Design - Why God Isn't as Smart as She Thinks She Is. 'The means are devious, the arguments deceitful and the consequences profound.'"
technorati tags: science, abc, broadcaster, robyn, williams, intelligent+design, unintelligent+design, creationism, publicity, life, complex, god, designer, intelligent, us, president, george+bush, schools, terrorism
Organisms, including humans, all inherit DNA from generation to generation, what biologists call hard inheritance, because the nucleotide sequence of DNA is constant and only changes by rare random mutation as it is passed down the generations.
But there also is evidence, especially in plants, that non-genetic factors modifying the DNA can also be inherited. The modifications of the genetic material take the form of small chemical additions to one of the DNA bases and the alternative packaging of the DNA. These so-called epigenetic modifications are known to be important for turning genes on and off during the course of an organism's life, but their importance in controlling inheritance has been debated. Many biologists are skeptical of any form of soft inheritance, where the genetic material is not constant, believing that it is only genetic information - DNA -- that can be passed onto generations.
Now Eric Richards, Ph.D., professor of biology at Washington University in St. Louis, writing in the May issue of Nature Reviews Genetics (Abstract), analyzes recent and past research in epigenetics and the history of evolution and proposes that epigenetics should be considered a form of soft inheritance, citing examples in both the plant and mammalian kingdoms.
In doing so, he evokes the pre-Darwinian evolutionist Jean-Baptiste Lamarck (1744-1829), a name that evolutionary biologists thought long ago left the stage, and Soviet agronomist T.D. Lysenko. Lamarck, and more recent neo-Lamarckian researchers, believed that the environment plays a key role in a species acquiring inherited characteristics that drive variation and evolution.
See an online edition of Lamarck's Zoological Philosophy
Richards' paper also appears in the Wanted Papers category.
How does a growing organism determine what its final body size will be? In the moth Manduca sexta, also known as the tobacco hornworm and recognisable by its distinctive blue-green caterpillar, adult body size is largely determined at the end of larval life, when the caterpillar has reached it final weight and is about to metamorphose into a moth.
In a study published today in the open access journal Journal of Biology, Frederik Nijhout, from Duke University in Durham, USA and colleagues built a new mathematical model that allows them to predict the size of an adult moth, on the basis of three parameters: the initial weight of the juvenile caterpillar, its growth rate and the rate at which the effect of a developmental hormone decays.
Paper referred to above: A quantitative analysis of the mechanism that controls body size in Manduca sexta.
There's also a minireview (The proximate determinants of insect size) in the same Journal of Biology issue which requires free registration (or use your BioMed identity if you have one).
Thursday, August 03, 2006
It's a rare occasion when a scientist gets an up-close look at dinosaur skin - or at least the fossilized impression of dinosaur skin.
Brian Platt, a doctoral student in geology at the University of Kansas, traveled to Wyoming last spring for his research project. At a recently discovered dinosaur track site at the Jurassic Morrison Formation, Platt and his adviser, Steve Hasiotis, associate professor of geology at KU, examined multiple tracks to find impressions of dino-skin, left by such sauropods as Brachiosaurus or Apatosaurus.
"The way the site is, the tracks are preserved as natural casts on the underside of sandstone. Because they're underneath the sandstone you can't see the tracks unless they weather away," Platt said.
To the untrained eye, the casts look more like small boulders tucked at the bottom of a layer of rock.
But under one cast Hasiotis found a textured surface made of raised polygonal shapes with about five or six sides, each about a centimeter in width. In between the tiny shapes, the skin appeared to recess into a v-shape, attached by small spurs of skin.
Palaios, a journal that emphasizes the impact of life on Earth's history, published Platt's and Hasiotis' findings in June (Abstract).
A new arms race: 'Evolutionism' is now an ideological weapon, but Darwin's own formulation was far more sophisticated
Although given in Rome, Cardinal Paul Poupard's speech in November about the distinction between evolution and evolutionism echoed throughout the world. Poupard, following the line of Pope John Paul II, acknowledged that evolutionary theory was no longer a mere hypothesis. Poupard's concern was to recognize the importance of the theory of natural selection in understanding life without acknowledging the theory's transformation into an ideological weapon.
The distinction between evolution and evolutionism is of extreme relevance. Michael Ruse's recent The Evolution-Creation Struggle sharply distinguishes between the fact of evolution by natural selection, including the theoretical explanations for this fact, and evolutionism as a naturalistic worldview with the characteristics of a secular religion. To recognize the important distinction between these points, it is necessary to understand how evolutionary theory developed. Evolution doesn't necessarily imply a mechanistic metaphysics, and the integration of legitimate, proven science into religion will break down the barriers between science and religion...
...Significantly, "the Baldwin Effect" also encompasses feedback by living organisms on their environment. This feedback can be thought of as "niche construction," a concept that has raised a good deal of recent interest...
See an online edition of "A New Factor in Evolution," by James Mark Baldwin (published in 1896).
Cardinal Poupard is also author of "Galileo Galilei - Towards a Resolution of 350 Years of Debate'", quoted in "An Error In Associating Lamarck With 'Adaptive Mutations'?"
technorati tags: rome, cardinal, poupard, evolution, evolutionism, pope, john+paul+II, natural+selection, ideological, michael+ruse, creation, secular, religion, mechanistic, metaphysics, science, baldwin+effect, galileo, lamarck
The first fossilised bone marrow has been found in the bones of 10-million-year-old frogs, salamanders and tadpoles by scientists working in northeastern Spain, the Irish team leader said Tuesday.
Palaeontologist Maria McNamara said the find could yield unprecedented insights into prehistoric creatures, such as whether they hibernated or whether they were cold-blooded or warm-blooded.
McNamara, a researcher at the School of Geological Sciences of University College Dublin (UCD), said her team from Ireland, Spain and the United States found the fossils in ancient lake deposits in the Libros area of Spain.
McNamara said one of the most exciting aspects of the discovery is what the marrow will be able to tell scientists about creatures that lived during what is known as the later Miocene period.
"The original organic material is still there," according to McNamara, whose research was published in this month's Geology (Abstract), the journal of the Geological Society of America.
Also see this earlier news item.
Scientists led by a Children's Hospital of Pittsburgh geneticist have found new evidence that a category of genes known as pseudogenes serve no function, an important finding that bolsters the theory of evolution.
There are approximately 20,000 pseudogenes in the human and other mammalian genomes. In recent years, there has been growing discussion about the nature of these pseudogenes. The issue centers on whether pseudogenes are functional or merely evolutionary relics with no function. It was long believed by geneticists that they were relics, until basic science research published in 2003 found a mouse pseudogene located within the Makorin family of genes that did have a function, namely to cause polycystic kidney disease and a bone disease known as osteogenesis imperfecta.
..."Discussion over evolution and Intelligent Design really has centered on whether pseudogenes, sometimes called 'junk DNA,' have a function or not. The suggestion is that an Intelligent Designer would not make junk DNA, so if a pseudogene does have a function, this is claimed to support the idea of an Intelligent Designer," Dr. Nicholls said. "But there is no evidence that any of the 20,000 pseudogenes are functional. Our research proves this Makorin pseudogene does not have a function."
The abstract of the Proceedings of the National Academy of Sciences paper the above is based on can be found here.
In an update to the above article published on Monday the Washington Post now reports:
A member of the state Board of Education who approved new classroom standards that call evolution into question held onto his seat Tuesday, turning back a challenge from two defenders of Darwin.
John Bacon won his primary with 49 percent of the vote. Two pro-evolution challengers split the remaining vote, including one who had been a leading critic of the anti-evolution standard.
Wednesday, August 02, 2006
"Lawrence, Kansas - The University of Kansas is sponsoring a three-month series of lectures about evolution and intelligent design, and organizers hope it will spark a broad public discussion.
The 'Knowledge: Faith and Reason' series is scheduled to start Sept. 7 with a lecture by Kenneth Miller, a Brown University biology professor who often defends evolution and says it can be reconciled with religious faith.
Last year, the Kansas State Board of Education adopted new science testing standards for public schools suggesting that some evolutionary theory was controversial or had been challenged, views that defy mainstream science."
Other Speakers are Judge John Jones III, Os Guinness, Richard Dawkins (author of The God Delusion: Amazon UK | US), Eugenie Scott (author of Evolution vs. Creationism - An Introduction: Amazon UK | US) , and Michael Behe (author of Darwin's Black Box: The Biochemical Challenge to Evolution: Amazon UK | US). A Panel Discussion will conclude the series. The original Kansas University News Release can be found here.
Also see Monday's Washington Post article "Election Could Flip Kansas Evolution Stance" (a link to the comments John Rennie - editor of Scientific American - made in a blog can be found at the end of this post).
technorati tags: lawrence, kansas, biodiversity, institute, lectures, reason, faith, dover, science, religion, intelligent+design, knowledge, jones+III, os+guinness, richard+dawkins, eugenie+scott, michael+behe, kenneth+miller, evolution
Tuesday, August 01, 2006
Ames, Iowa - Theoretical biologist Stephen Proulx studies gene families to explore how genomes become diverse and evolve. The Iowa State University assistant professor uses mathematical tools and computer models to determine how environmental and evolutionary factors - like seasonal change, migration and sexual preference - structure a genome...
...In a recent paper published in the journal Evolution (Abstract), Proulx and colleague Patrick Phillips, professor, University of Oregon, Eugene, show that the process of gene family expansion can begin even before a gene is duplicated. The first step in the process involves specialization of different variants of a gene that can then take on different functions once the gene is duplicated by chance.
Washington Post: Chicago, July 31 - Evolution's defenders, working to defeat Kansas Board of Education members who oppose modern Darwinian theory, are challenging three incumbent Republican conservatives and the political heir to a fourth in Tuesday's primary.
A shift of two seats to moderate Republicans - or to Democrats - in November almost certainly would lead to a reversal of state science standards celebrated by many religious conservatives and reviled by the scientific establishment.
With turnout expected to be low, neither side is making confident predictions about the state's latest skirmish at the intersection of science, religion and politics. The board's majority shifted to the moderate side in 2000 only to swing back in 2004.
...The editor of Scientific American, John Rennie - who has described the board's conservatives as "six dimwits" - posted on a blog to urge Kansas voters to defeat board members "who have inflicted embarrassing creationist nonsense on your home's science curriculum standards...
John Rennie's blog comments ("Kansas, Undo the Damage") can be found here.
Update, August 3rd: The above article is no longer available because it's been 'overwritten' (ie the same url has been used) by "Anti-Evolution Incumbent in Kansas Wins".
The last thing McGill University professor Brian Alters expected upon opening a letter late in March was to see his latest $40,000 Canadian ($36,400 US) grant rejected for not providing enough evidence to support a theory he'd made a career of defending: evolution.
Alters had applied for funds from Canada's Social Sciences and Humanities Research Council (SSHRC) to study the effect of intelligent design debates in the United States on Canadian students, teachers, administrators, and policymakers. In the rejection letter, the SSHRC said Alters - who is a vocal advocate for education about evolution and an expert witness in the recent Dover trial - did not provide 'adequate justification for the assumption in the proposal that the theory of evolution, and not intelligent design theory, was correct.'
Alters says he was completely blown away to read that one of Canada's largest funding bodies seemed to consider intelligent design an alternative scientific theory to evolution. Coincidentally, he received the letter a few days before giving a Canadian Royal Society lecture on 'Intelligent Design, God, and Evolution.' (Webcast - see Note 2). Alters read the six-sentence rejection aloud to the 650 people attending, and 'there was an audible gasp in the audience,' he says.
Note 1: email if you have problems accessing this article
Note 2: For 20 or 30 seconds the webcast page said 'loading' and appeared to be redirected because of my pop-up settings. Have patience and ignore any 'NoPopupRedirector' message (or check your pop-up settings if the page doesn't load at all of course!).
technorati tags: mcgill, university, professor, alters, theory, evolution, social+sciences, humanities, research, intelligent+design, canada, united+states, dover+trial, evolution, funding, alternative, royal+society, god, webcast
Monday, July 31, 2006
Dinosaur dung and fossilised footprints have been unearthed at a Broadbridge Heath quarry in what experts have dubbed the most exciting prehistoric Horsham district finds for more than 60 years.
The discoveries have been examined by fossil specialists at Brighton University and Brighton Museum and confirmed as the footprints of an Iguanodon and a Polacanthus, and the faeces of a small dinosaur or large crocodile.
The fossils are all more than 100 million years old.
The Polacanthus footprint was discovered by University of Kansas professor Stephen Hasiotis during a tour of the Historic Horsham Stone Quarry, in Lower Broadbridge Heath Farm, on Saturday July 22.
Roger Birch, geologist teacher at Collyer's Sixth Form College, in Hurst Road, Horsham, and author of West Sussex Stone: The Story of Horsham Stone, has described the finds as 'extremely rare' and 'very exciting'.
Francis Crick, Discoverer of the Genetic Code, by Matt Ridley - a New York Times (may require free registration) book review:
Francis Crick has never before been the subject of a significant biography. His personality, however, is the subject of one of the best-known lines in science literature. "I have never seen Francis Crick in a modest mood," James Watson declared in the first sentence of "The Double Helix" (1968), his celebrated account of how he and Crick came to identify the structure of DNA in 1953. Thus the popular image of Watson's scientific partner: a brash and boastful figure who shared responsibility for a singular breakthrough.
Now, two years after Crick's death at age 88, the science writer Matt Ridley is attempting to revise the historical record. Ridley's short biography examines the paired strands of Crick's life and work, but gives the work a further twist: in his account, the heart of Crick's career merely began in 1953, and lasted until the mid-1960's, during which time Crick, having deduced DNA's form, led the scientific charge to understand how it functions. Ridley claims this effort was "in many ways a greater scientific achievement than the double helix," and his own effort to explain it should deepen his audience's understanding of both Crick and DNA itself.
"Francis Crick, Discoverer of the Genetic Code" is currently appearing on the 'Featured Books' page of the Evolution Book Store: UK | US)
See Molecular Structure Of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid - Watson and Crick's historical 1953 paper
A honeybee's ability to smell scent appears to be linked to the right side of its brain, according to a new ANU study that could show how right and left 'handedness' evolved in other species.
"Just as humans use different brain hemispheres for different tasks, it appears honeybees and other insect species may also be right or left 'brained' for certain activities," PhD student Pinar Letzkus from the ANU Research School of Biological Sciences said.
...The study, published in the journal Current Biology (Abstract), is the first time that a right/left tendency for odour recognition has been shown in creatures such as insects, which have small and relatively simple brains.
...Ms Letzkus said the results could shed light on brain physiology and evolution more generally.
"But there is still much to be answered. One of the biggest questions is whether this system of left/right demarcation has evolved separately in insects and mammals, or whether it's a primitive system that for some reason has been genetically conserved in the evolutionary process."
Sunday, July 30, 2006
Simon Ho grew up near the surf beach at Maroubra. Now the 25-year-old Australian is making big waves in the scientific world.
Dr Ho, a biologist and computer scientist, has uncovered flaws in the method other researchers have been using for decades to estimate when different species evolved, forcing many to reconsider their dates.
His research suggests modern humans arose much more recently than had been thought.
'Basically, any studies that look at evolution in the past million years need to be re-evaluated, so a lot of people are quite defensive about that,' said Dr Ho, who has just been awarded a doctoral degree at Oxford University in Britain for his findings.
See "Relaxed Phylogenetics and Dating with Confidence" (pdf file)
The Reluctant Mr. Darwin: Book Review by David Quammen:
The only thing most people know about Charles Darwin is that he took a boat to the Galapagos Islands where he encountered life forms that prompted him to invent the theory of evolution. As it happens, even that's not exactly right.
Darwin didn't invent the theory of evolution. While scientific and religious orthodoxy in Victorian England held that plants and animals hadn't changed since the day God created them, the idea that species alter over time had long been in the air.
Darwin's achievement lay in working out the means by which evolution takes place: natural selection.
...We may be fuzzy on some of Darwin's ideas and have no clue about Darwin the man, but that hasn't stopped us from turning his name into a fighting word. The latest generation of anti-evolutionists marches under the banner of "creationism" and "intelligent design" and apparently enjoys a large pool of potential recruits. According to science writer David Quammen, author of this useful introduction to Darwin's life and thought, 45 percent of Americans in a 2004 Gallup Poll agreed with the statement: "God created human beings pretty much in their present form at one time within the last 10,000 years or so." Another 38 percent agreed that humans "have developed over millions of years from less advanced forms of life, but God guided this process..."
...Quammen's book is a contribution to James Atlas' series Great Discoveries, which aims to loose graceful prose writers on important scientific topics to produce short books accessible to nonspecialists.
The Reluctant Mr. Darwin, with 253 pages of text, leaves out a lot. Quammen omits entirely Darwin's voyage to the Galapagos. The discussion of Darwinism's post-1859 reception is hectic and unsatisfying. The great man's personality remains elusive.
The Reluctant Mr. Darwin is currently appearing on the 'Featured Books' page of the Evolution Book Store: UK | US)
UPDATE: See "Evolution and Its Discontents" (Washington Post, Sunday, August 27, 2006) for book reviews of The Reluctant Mr. Darwin and also Why Darwin Matters: The case against intelligent design (by Michael Shermer: blog entry)
technorati tags: natural+selection, book+review, darwin, galapagos, theory, evolution, creationism, intelligent+design, science, quammen, god, darwinism, reluctant, mr, intelligent+design, washington+post, shermer
Guardian UK Book Review: After 40 years of studying the problem of consciousness, Nicholas Humphrey believes it was natural selection that gave us souls. God, he insists, had nothing to do with it.
The distance between a neurone and a human mind seems very great, and to many philosophers and scientists quite impossible for science to cross. Even if minds are made from brains, and brains are made from billions of neurones, there seems no way to get from one sort of thing to the other.
Nicholas Humphrey's whole life as a scientist has been spent on that journey: in the 1960s he was part of the first team to discover how to record the activity of single neurones in a monkey's visual cortex; nearly 40 years later, he has reached a grand theory of how consciousness might have arisen in a Darwinian world, and why it might give us reasons to live.
...The theory is, like every other theory of consciousness, extremely controversial. After 200 years in which science has appeared to dethrone God and deny the possibility of the soul, Humphrey is the first man to claim that science can agree that we have souls - but that it was natural selection, not God, which gave us them. [Mind, Soul, and Brain]