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A Home for Herbie
Generous with kisses and full of wonder, Herbie now tips the scale at a healthy 60 pounds. He is thriving in his new habitat. Herbie has joined 16-year-old resident harbor seal Nicky, who is helping to show the youngster the ropes. He has also formed strong bonds with his keepers, who describe him as bright and particularly eager to learn. Zoo Sanctuaries While the vast majority of animals who reside in accredited zoos are born in captivity, Herbie is not the only rescued wild animal that has found a safe haven with WCS. Grizzly bears Betty, Veronica, Jughead, and Archie were saved from euthanasia and brought to the Bronx Zoo by the U.S. Fish and Wildlife Service. Considered "nuisance bears," they had been encroaching on human habitat-a problem that leads to all sorts of conflicts in places throughout the world where animals and people share their turf. At the Queens Zoo, brother and sister mountain lions, Felix and Cleo, were found as orphans after their mother was killed in Montana. And bald eagles Claire and Mel were also rescued from the wild, unable to fly due to wing injuries. Residing comfortably at the Prospect Park Zoo is Snickers, a great horned owl who suffered a wing injury after an unfortunate run-in with barbed wire......... Posted by: Kelly Permalink Source Walrus Calves Stranded By Melting Sea Ice
A walrus pup alone in the Arctic Ocean, one of nine calves seen swimming far from shore and presumed to have died. (Photo by Carin Ashjian, Woods Hole Oceanographic Institution) Scientists have reported an unprecedented number of unaccompanied and possibly abandoned walrus calves in the Arctic Ocean, where melting sea ice may be forcing mothers to abandon their pups as the mothers follow the rapidly retreating ice edge north. Nine lone walrus calves were reported swimming in deep waters far from shore by researchers aboard the U.S. Coast Guard icebreaker Healy during a cruise in the Canada Basin in the summer of 2004. Unable to forage for themselves, the calves were likely to drown or starve, the scientists said. Lone walrus calves far from shore have not been described before, the researchers report in the recent issue of Aquatic Mammals. The sightings suggest that increased polar warming may lead to decreases in the walrus population. "We were on a station for 24 hours, and the calves would be swimming around us crying. We couldn't rescue them," said Carin Ashjian, a biologist at Woods Hole Oceanographic Institution and a member of the research team. The researchers found evidence of warmer ocean temperatures that may have rapidly melted seasonal sea ice over the shallow continental shelf where walruses dive to feed on bottom-dwelling animals such as clams and crabs. Walrus need the ice to rest themselves and to leave the pups to rest while the mothers feed. Ice remained over very deep water......... Posted by: Kelly Permalink Source Small, Loud, Eusocial And Successful
Eusocial (truly social) animals are not very common. Only nine groups are known to be eusocial, eight of them live in terrestrial environments
STRI postdoctoral fellow Eva Toth doing research on Bocas del Toro, studies eusocial snapping shrimps, that have colonies with tens to hundreds of members with one reproductive female, a large queen carrying the embryos. These shrimp are smaller than their pair-living cousins, also sponge-dwelling animals. These eusocial shrimps are equipped with an enlarged snapping claw that they use for communication and combat. By closing the fingers of their claws very rapidly, they send a water jet to their opponent, thereby indicating their strength. As a byproduct, an audible crackling sound is produced, hence their popular name. When conflict escalates they can grab and cut their opponents with their claws. Eva focuses on how these small shrimps are able to successfully compete for their host sponges with their larger cousins. She also compares their colony structure and organization with terrestrial social animals......... Posted by: Kelly Permalink Source Call To Help Wildlife
Louisiana populations of the swallow-tailed kite may be helped by cell phone technology adapted by MIT MLK Visiting Professor Dale Joachim. Photo / U.S. Fish and Wildlife Service
In his studies of communication among birds, Joachim applies sensor and signal processing methods to "something very dear to me -- nature conservancy," he said. Currently, wildlife biologists monitor populations of some bird species by standing in the birds' habitat, replicating particular birdcalls and logging and analyzing the responses they get. Joachim hopes to establish an encoded form of birdcalls suitable for remote cell phone broadcast. Once programmed to broadcast birdcalls, the cell phones will also serve as channels, sending the birds' responses back to a home base for logging and analysis. Joachim has focused initially on the conservation of swallow-tailed kites -- birds native to Louisiana whose population is "being decimated by great horned owls," he said. Success in his research could lead to federal certification of cellular telephones for use in conservation monitoring programs, Joachim said. Joachim also studies the cognitive processes involved in accurately recognizing specific chords within musical compositions. He hopes to develop intelligent systems to automate musical chord transcription and, ultimately, to "emulate a human bass player's understanding sufficiently well to play a coherent bass line accompaniment," he said......... Posted by: Kelly Permalink Source Modelling virtual dogs
Caption: A walk in the Park: Labrador 'Buster' with walker Sarah Credit: J. Usherwood Dog walking is a national pastime, but how does your dog walk? Different breeds have different gaits, for example greyhounds tend to be thin and fast whilst labradors are thicker set and tend to waddle. Using computers to simulate the way dogs walk, researchers at the Royal Veterinary College in London have found that fairly simple models can be used to explain the mechanics of canine locomotion. "This technique could help us understand the mechanics behind walking problems such as hip dysplasia", says Dr Jim Usherwood who is leading this investigation and will be presenting his latest results at the Annual Meeting of the Society for Experimental Biology on Tuesday 4th April [session A7]. Dr Usherwood first made different computer models of a walking dog and then compared these with observations of actual dogs on a treadmill. He found that the way dogs walk can be explained using a surprisingly simple passive stiff-limbed model. "We already know a lot about bipedal movement; but we wanted to understand quadrupedal movement and were surprised that the mechanics involved are less complicated than we first imagined". Usherwood was partly inspired by his colleagues David Lee and Andy Biewener at Harvard, who in collaboration with Boston Dynamics are involved in designing 4-legged robots with potential military or rescue applications......... Posted by: Kelly Permalink Source Simple Developmental Changes Gave Bats Flight
A bat skeleton at day 80 of embryonic development. Bone appears in red and cartilage in blue. Image credit: Scott Weatherbee, Memorial Sloan Kettering Cancer Center
The fossil record indicates that bats, the only mammals with powered flight, date back to the Eocene, an era that began approximately 55 million years ago. Notably, bat wing anatomy has not changed substantially over the past 50 million years - an observation that served as a starting point for the new work, which was published April 17, 2006, in an advanced online publication of the Proceedings of the National Academy of Sciences. "We saw that the evolution of flight was quite sudden," said Lee A. Niswander, a Howard Hughes Medical Institute investigator at the University of Colorado Health Sciences Center who led the study. "That means there could be just a few key changes in limb development that resulted in more dramatic downstream consequences". To find those key changes, Niswander and colleagues focused on the third, fourth, and fifth digits of the bat forelimb. These digits - equivalent to a human's middle, ring, and pinky fingers - are highly elongated and provide the support necessary for the wing membrane to be used for flight......... Posted by: Kelly Permalink Source Fruitfly Study Shows How Evolution Wings It
In the frantic world of fruitfly courtship, the difference between attracting a mate and going home alone may depend on having the right wing spots. Now, Howard Hughes Medical Institute scientists have learned which elements of fly DNA make these spots come and go in different species. Their studies have also uncovered surprising new evidence supporting the idea that evolution is an incessant tinkerer when it comes to complex traits. The experiments are among the first to root out "the deep mechanics of evolution" that underpin complex traits, as per the study's senior author Sean Carroll, a Howard Hughes Medical Institute researcher at the University of Wisconsin-Madison. Carroll and his Wisconsin colleagues collaborated with scientists from the University of Cambridge and Stony Brook University on the studies, which were reported in the April 20, 2006, issue of the journal Nature. The scientists said their findings emphasize the evolutionary significance of "pleiotropic" genes - those with multiple on-switches that enable the expression of a single gene in different tissues or at different stages of development. "The wing spot on the fruitfly is a especially good model because we know it constitutes a new feature that is gained or lost by evolution in different species," said Carroll. "And, since it is a spatial pattern, it gives us a chance to analyze the evolution of a physical trait. Such traits have size, shape, and length, and they are more complicated than physiological traits. For example, eye color is not a tricky thing to figure out, since it can be reduced to single genetic changes. But evolutionary biologists want to understand how even complicated bits of anatomy and machinery - like the wing or the complex eye - are put together in the course of evolution."........ Posted by: Kelly Permalink Source The Best Parent For Your Chicks
Who's chosen by whom in the mating game is determined by seasonal changes in the genetic diversity of available mates, as per new research based on a 10-year study of wild finches. The finding helps explain a long-standing evolutionary biology paradox. Prior research has shown that female birds often go for the flashier guys. A number of biologists argue that sexual selection -- competition for mates -- is the driving force behind the evolution of such elaborate and seemingly useless getups as a male peacock's tail. "For such elaborate traits to evolve, you have to have mating patterns where everyone wants the same thing," said lead researcher Kevin P. Oh of The University of Arizona in Tucson. But if everyone mates with the same perfect-looking individual, ultimately that would result in inbreeding, he said. Especially healthy kids are produced when the parents are genetically different -- what biologists call complementarity. However, choosing one's genetic better half would generate more diversity in looks, rather than pushing the population toward a uniform dandified appearance. Alexander V. Badyaev, principal investigator for the UA study, said, "Even though preference for genetically complementary mates is widely documented, it'TMs always puzzled people that individual differences in mate preference do not prevent the evolution of elaborate ornaments"......... Posted by: Kelly Permalink Source Animal Brains Adapted To Recognize Predator's Foot Movements
"We believe this visual filter is used to signal the presence of animals that are propelled by the motion of their feet and the force of gravity," suggests Dr. Troje, Canada Research Chair in Vision and Behavioural Sciences. Conducted with Dr. Cord Westhoff from the Ruhr-Universität Bochum in Gera number of, the study was funded by the Canada Foundation for Innovation and the German Volkswagen Foundation. It will be published on-line April 18 in the international journal Current Biology. The scientists suggest this low level locomotion detector is part of an evolutionary old system that helps animals detect quickly - even on the periphery of their visual field - whether a potential predator or prey is nearby. "Research on newly hatched chicks suggests that it works from very early on in an animal's development," says Dr. Troje. "It seems like their brains are 'hard wired' for this type of recognition." One impetus for starting this research several years ago was a question by his young daughter, who asked him why she could get so much closer to wild rabbits in their neighborhood while riding on her bicycle rather than on foot. "I didn't have an answer for her then. Now, I think I have one," he says......... Posted by: Kelly Permalink Source Masters Of Disguise
Cuttlefish are wizards of camouflage. Adept at blending in with their surroundings, cuttlefish are known to have a diverse range of body patterns and can switch between them almost instantaneously. New research from MBL Marine Resources scientists, to appear in the May 2006 issue of the journal Vision Research, confirms that while these masters of disguise change their appearance based on visual cues, they do so while being completely colorblind. While prior research has reported cuttlefish colorblindness, MBL Research Associate Lydia Mäthger and her colleagues in Roger Hanlon's laboratory approached the problem in more depth and with a new behavioral assay. The scientists tested cuttlefish (Sepia officinalis) color perception through observing the animal's behavioral response to a series of checkerboard patterned substrates of various colors and brightnesses. They found that the animals did not respond to the checkerboard pattern when placed on substrates whose color intensities were matched to the Sepia visual system, suggesting that these checkerboards appeared to their eyes as uniform backgrounds. However, their results showed that cuttlefish were able to detect contrast differences of at least 15%, which Mäthger and her colleagues suspect might be a critical factor in uncovering what determines camouflage patterning in cuttlefish......... Posted by: Kelly Permalink Source |
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