Building The Body Electric. The invasive species war. EARLIER THIS MONTH, a troop of volunteers in Newton piled into canoes and went to war in the name of the Charles River. They wore gloves to protect themselves from their enemy: a thorny aquatic plant called the European water chestnut, believed to have invaded the Charles a century ago after escaping from the Harvard botanical garden. The plant spread swiftly, growing so thick in some areas that it overwhelmed the waterway entirely. For the past four years, the Charles River Watershed Association has led the effort to get rid of the pest, recruiting concerned citizens to pull the unwanted plants out by their roots and collect them in plastic laundry baskets.
The European water chestnut is considered an invasive species, one of the 1,500 or so plants and animals across the United States that have ended up settling in places where they don’t belong because of human activity. In the past several months, however, that idea has come under blistering attack. Meet the Contenders for Earliest Modern Human | Hominid Hunting. Iceman’s Genome Furnishes Clues to His Ailments and Ancestry. The Iceman is a 5,300-year-old mummy discovered in the Ötzal Alps. Image: Samadelli Marco/EURAC Ever since two hikers happened upon the mummified body of Ötzi the Iceman on a high mountain pass in the Ötzal Alps in 1991, scientists have been working to figure out who he was and where he came from. Previous research indicated that Ötzi spent his life within a 60-kilometer radius of where the hikers found him and died around 5,300 years ago, most likely from an arrow wound in his shoulder.
Now the sequencing of his genome is allowing experts to fill in more details, such as the color of his eyes, his cardiovascular health and where his ancestors originated. Albert Zink of the European Academy of Bozen/Bolzano in Italy and his colleagues report the results of the sequencing work in a paper published today in Nature Communications (Scientific American is part of Nature Publishing Group). Genetic analysis suggests that the Iceman had brown eyes, as shown in this artist's reconstruction. New Ant Species Discovered in the Amazon Likely Represents Oldest Living Lineage of Ants. Sept. 16, 2008 AUSTIN, Texas — A new species of blind, subterranean, predatory ant discovered in the Amazon rainforest by University of Texas at Austin evolutionary biologist Christian Rabeling is likely a descendant of the very first ants to evolve. The new ant is named Martialis heureka, which translates roughly to "ant from Mars," because the ant has a combination of characteristics never before recorded.
It is adapted for dwelling in the soil, is two to three millimeters long, pale, and has no eyes and large mandibles, which Rabeling and colleagues suspect it uses to capture prey. The ant also belongs to its own new subfamily, one of 21 subfamilies in ants. This is the first time that a new subfamily of ants with living species has been discovered since 1923 (other new subfamilies have been discovered from fossil ants). Rabeling says his discovery will help biologists better understand the biodiversity and evolution of ants, which are abundant and ecologically important insects.
Swarm troopers: Mutant armies waging war in the wild - life - 12 September 2011. Read full article Continue reading page |1|2|3 We can now genetically modify animals to kill off their own kind, while leaving other species unharmed Editorial: "Give geo- and genetic engineering a fair trial" IN THE urban jungle of Juazeiro in Brazil, an army is being unleashed. It is an army like no other: the soldiers' mission is to copulate rather than fight.
But they are harbingers of death, not love. Their children appear healthy at first but die just before they reach adulthood, struck down by the killer genes their fathers passed on to them. These soldiers are the first of a new kind of creature - "autocidal" maniacs genetically modified to wipe out their own kind without harming other creatures. In essence, much the same method has already been successfully employed for more than half a century. Infographic: Compare the sterile insect and autocidal techniques This method is widely used and has notched up many successes. So why isn't the method more widely used? More from the web. Genetics Explain How Bedbugs Infest a Building--or a Country. PHILADELPHIA—When you have bedbugs (Cimex lectularius), less interesting is the question of how they got there than the conundrum of how best to get them out. Ridding homes and businesses of these pests has become a multimillion dollar industry in many cities in the U.S. and throughout the world.
A few scientists, however, are now asking just how these populations have been spreading from town to town and from headboard to headboard. Answering that question might lead to better ways of controlling their spread into the future. Researchers are using genetics to try to trace bedbug lineages in the U.S. as well as those in individual apartment buildings. "It's actually kind of a forensics question," Coby Schal, an entomologist at North Carolina State University in Raleigh, said at the American Society of Tropical Medicine and Hygiene's annual meeting in Philadelphia on Tuesday.
In a poultry house, however, a bedbug would not be exposed to the same insecticides as one living among humans. “Zombie” Fly Parasite Killing Honeybees. A parasitic fly landing on a honeybee. Courtesy of Christopher Quock A heap of dead bees was supposed to become food for a newly captured praying mantis. Instead, the pile ended up revealing a previously unrecognized suspect in colony collapse disorder—a mysterious condition that for several years has been causing declines in U.S. honeybee populations, which are needed to pollinate many important crops.
This new potential culprit is a bizarre—and potentially devastating—parasitic fly that has been taking over the bodies of honeybees (Apis mellifera) in Northern California. John Hafernik, a biology professor at San Francisco State University, had collected some belly-up bees from the ground underneath lights around the University’s biology building. “But being an absent-minded professor,” he noted in a prepared statement, “I left them in a vial on my desk and forgot about them.” Parasitic fly larva emerging from a dead bee's neck. The parasitic fly lays eggs in a bee’s abdomen. Dirty Dancing: Dung Beetles Get Down to Walk the Line. As a dung beetle rolls its planet of poop along the ground it periodically stops, climbs onto the ball and does a little dance. Why? It's probably getting its bearings. A series of experiments published in the January 18 issue of PLoS ONE shows that the beetles are much more likely to perform their dance when they wander off course or encounter an obstacle.
Until now, no one had any idea what a jitterbugging dung beetle was up to. Emily Baird of Lund University in Sweden and her colleagues study how animals with tiny brains—such as bees and beetles—perform complex mental tasks, like navigating the world. The dung beetle intrigues Baird because it manages to roll its dung ball in a perfectly straight line, even though it pushes the ball with its back legs, its head pointed at the ground in the opposite direction.
If the six-legged Sisyphus can't see where it's going, how does it stay on its course? Every now and then, a dung beetle stops rolling, mounts its ball and pirouettes. New fruit fly gene discovered. Provided Drosophila melanogaster Scientists thought that most new genes were formed from existing genes, but Cornell researchers have discovered a gene in some fruit flies that appears to be unrelated to other genes in any known genome. The new gene, called hydra, exists in only a small number of species of Drosophila fruit flies, which suggests it was created about 13 million years ago, when these melanogaster subgroup species diverged from a common ancestor. And early evidence indicates that the new gene is functional (as opposed to being nonfunctional "junk" DNA) and is likely to express a protein involved in late stages of sperm cell development (spermatogenesis).
"This is a de novo -- 'out of nowhere' -- gene," said Hsiao-Pei Yang, a senior research associate in Cornell's Department of Molecular Biology and Genetics and senior author of a paper published in the July 6 issue of the online journal PLoS Genetics (Public Library of Science Genetics). Let's protect Earth's unseen life - opinion - 06 March 2012. Microbes are being failed by existing conservation efforts. We need a global strategy to ensure their survival "IF THE last blue whale choked to death on the last panda, it would be disastrous but not the end of the world. But if we accidentally poisoned the last two species of ammonia oxidisers, that would be another matter. It could be happening now and we wouldn't even know. " The words of environmental engineer Tom Curtis sum up the seeming disregard for microbial life beautifully. The tree of life is diverse.
The neglected kingdoms are broadly microbial and comprise by any measure, be it their biomass or genetic diversity, the "unseen majority" of life. No. You only have to look at mainstream conservation journals to see the macrobial bias: only 2 per cent of papers relate to microbes, and even then mostly as threats to larger organisms rather than being concerned with their preservation.
It could be argued that protecting the ecosystem will suffice to protect its microbes. Bony Bacteria. The Dwindling Web. Humans have harvested the sea for tens of thousands of years, but only in the past few centuries have we begun to take a big toll on ecosystems. The two food webs below show predatory relationships among life-forms in the northern Adriatic Sea. Each web comprises humans, their prey and the prey of humans’ prey, distilled into groups of species.
The webs, produced by Jennifer A. Dunne of the Santa Fe Institute from evidence compiled by Heike K. Graphic by Jennifer A. » Watch a video about food webs in this month's Graphic Science Web Exclusive "Food Webs Trace the Structure of an Ecosystem. " Island of Secrets: In search of a tree kangaroo on New Britain. In July of 2011, John Lane, an explorer and geologist from California State University-Chico, mounted a biological research expedition to a remote wilderness region of New Britain, a volcanic island off the coast of Papua New Guinea. The greater PNG region is a hotspot of biodiversity, but one that is highly threatened by oil palm plantations and other industries. Lane’s quest was to spur environmental conservation by finding a mysterious species of tree kangaroo, one of the rarest and most elusive mammals on earth, which natives had witnessed but scientists believed did not exist on New Britain. So with the help of local Nakanai tribesmen, several scientific researchers and a few Cal State students, Lane set up a base camp in a caldera deep in the forest, from which to conduct biological research and search for the creature.
This following is adapted from Matthew Power's account of the expedition, Island of Secrets, just published by The Atavist. Photograph by Dylan van Winkel. It Does Take a Village by Melvin Konner. Mothers and Others: The Evolutionary Origins of Mutual Understanding by Sarah Blaffer Hrdy Belknap Press/ Harvard University Press, 422 pp., $29.95; $19.95 (paper) Sarah Blaffer Hrdy is one of the most original and influential minds in evolutionary anthropology. She first became known for her field study of Hanuman langurs, the sacred monkeys that range widely in the Indian peninsula. They are large and sometimes dangerous, and Hrdy was among that second generation of bold primatologists, just behind Jane Goodall and Diane Fossey, who did original work with primates. Hrdy discovered, among other things, that dominant males in a group are challenged from time to time by roving adventurers who can mate only by defeating them.
If such behavior had been limited to langurs, it might have been an anomaly. Many years later, Hrdy took on another heroine of anthropology and psychology, the good mother. But this goddess too was a mere apparition. Hrdy has not been alone in challenging this myth. Forget love, biological sex is a battlefield. Gender isn’t a simple thing. A person can be male, female, both, neither, and more—and that identity doesn’t have to have anything to do with the particular genital plumbing they were born with.
But the plumbing itself—the biological sex, rather than gender or socio-cultural sex—is also a lot more complicated (and interesting) than we often give it credit for. Don’t believe me? Then check out “DMRT1 prevents female reprogramming in the postnatal mammalian testis,” a research letter published in September in the journal Nature. That title is full of typical peer-reviewed paper jargon, but let me break it down for you: There’s a genetic factor, present in male mammals, that is vital to making sure those mammals develop male sex characteristics.
But it’s not only important during embryonic development. The genetic factor is called DMRT1, and it is not the only thing responsible for maintaining a mammal’s biological sex throughout life. It all begins in utero. What’s that mean for humans? Pirate-Eye Pigeons Reveal How the Brain Talks to Itself.
As a baby bird develops, its body contorts to fit within the confines of its egg. The bird's neck twists so that one side of its head is tucked against its chest. In this position, the bird's left eye remains nestled among sprouting feathers—where it does not receive much light from the outside world—whereas the right eye is pressed up against the eggshell, glimpsing flickers of light and shadow through a veil of calcium carbonate.
Even though this uneven stimulation of the eyes lasts only one or two days before the chick hatches, it seems to be crucial for typical brain development. Pigeons incubated in the dark have a much harder time solving puzzles as adults than pigeons exposed to light before hatching. The reason, some researchers think, is that the brain's two hemispheres cannot properly integrate information if they miss a critical window period of learning in the egg. Martina Manns of Ruhr University Bochum in Germany has been studying pigeon brains for the past 20 years. Can the Bulldog Be Saved? Coyotes Are the New Top Dogs. By Sharon Levy of Nature magazine Near the dawn of time, the story goes, Coyote saved the creatures of Earth. According to the mythology of Idaho's Nez Perce people, the monster Kamiah had stalked into the region and was gobbling up the animals one by one.
The crafty Coyote evaded Kamiah but didn't want to lose his friends, so he let himself be swallowed. From inside the beast, Coyote severed Kamiah's heart and freed his fellow animals. Then he chopped up Kamiah and threw the pieces to the winds, where they gave birth to the peoples of the planet. European colonists took a very different view of the coyote (Canis latrans) and other predators native to North America. Researchers have long known the coyote as a master of adaptation, but studies over the past few years are now revealing how these unimposing relatives of wolves and dogs have managed to succeed where many other creatures have suffered. Yet even among such opportunists, coyotes stand out as the champions of change.
Dogs, But Not Wolves, Use Humans As Tools | The Thoughtful Animal. Humanity's Best Friend: How Dogs May Have Helped Humans Beat the Neanderthals - Megan Garber. Do Dogs Feel Guilty? | The Thoughtful Animal. Do the Eyes Have It? How to Build a Dog. Dogs - A Healthy Future. National Geographic Photography Contest Winners: 2011. Alan Turing's 60-Year-Old Prediction About Patterns in Nature Proven True.
Penn Researcher Helps Discover and Characterize a 300-Million-Year Old Forest, Preserved Like Pompeii. Do Plants Think? Deep Life. Buried microbes exist at limit between life and death - life - 17 May 2012. Defying Depth. Microbes Flourish Under Arctic Sea Ice. Patch of seagrass is world's oldest living organism - life - 06 February 2012. Researcher Sees Biological Regime Change Under Way in Alaska. How fairy wasps cope with being smaller than amoebas | Not Exactly Rocket Science. Zoologger: Unique life form is half plant, half animal - life - 13 January 2012.
The Smart Way to Play God with Earth's Limited Land. Watch How Life Recovers from Devastation. Plant blooms after 30,000 years in permafrost - life - 20 February 2012. A Rose is a Rose, Until it Isn’t: Five Reasons Plant DNA is Totally Crazy. Zoologger: Meet the polar bear's replacement - environment - 20 April 2012. Life-changing experiments: The biological Higgs.
Baboons Show Their Word Skills. Traces of Elusive Species Sought in Bloodsucking Leech DNA. 24 New Lizard Species Discovered, Half Close to Extinction. Bat-Killing Fungus Continues Deadly Spread; Death Toll Now at 7 Million | Extinction Countdown. Mounting Evidence Suggests Sharks Are In Serious Trouble | Science Sushi.