Final moments of bee landing tactics
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Freezing The Common Fruit Fly
Why is this important? Because the common fruit fly (Drosophila melanogaster) is one of the bugs that cannot survive freezing and the little creature just so happens to share much of the same genetic makeup as humans, therefore finding a way to freeze them for research purposes is a top priority for geneticists the world over (about 75 per cent of known human disease genes have a recognizable match in the genetic code of fruit flies). And why the large microscope?. "It's the only one in the world that's set up for this kind of imaging on insects," says lead researcher Brent Sinclair of his team's use of the Advanced Photon Source (APS), located near Chicago, Illinois. The APS generates high-energy x-rays that allow Sinclair and his collaborators to film the formation and spread of ice in real time as the maggots freeze. See video at here. An assistant professor in Western's Department of Biology, Sinclair explains that the physical processes of ice formation seem to be consistent among species that do and don't survive freezing. However, it seems that the insects that survive freezing have some control over the process of ice formation. They freeze at consistently higher temperatures than those that don't......... World's rarest gorilla ready for its close-up
This is a still from the first professional video of wild Cross River gorillas.
Credit: (c) NDR Naturfilm With the assistance of the Wildlife Conservation Society's Cameroon Program, a film crew from the Hamburg-based NDR Naturfilm managed to video the elusive Cross River gorilla earlier this year in a stand of montane trees after weeks of effort in the Kagwene Gorilla Sanctuary. The protected area was created in 2008, with the guidance of WCS, specifically to protect the world's rarest great ape. "These gorillas are extremely wary of humans and are very difficult to photograph or film," said Dr. Roger Fotso, Director of the Wildlife Conservation Society's Cameroon Program. "Eventually, we identified and staked out some of the gorillas favorite fig trees, which is where we finally achieved our goal". "It's unbelievable that one great ape subspecies has never been filmed for TV so far," said Jrn Rver, Head of NDR Naturfilm. "We hope that our international production helps to raise awareness for these magnificent creatures and the work of the WCS". The only prior footage available of the rare apes was taken from a long distance with a shaky, hand-held camera in 2005 by a field researcher......... Killer catfish?
A newly released study by University of Michigan graduate student Jeremy Wright finds that at least 1,250 and possibly more than 1,600 species of catfish appears to be venomous-far more than previously believed. The research is described in a paper published online Dec. 4 in the open access journal BMC Evolutionary Biology. Lest anyone have concerns about attacks of killer catfish, rest assured that, at least in North America, these finned fatales use their venom mainly to defend themselves against predatory fish, though they can inflict a painful sting that a number of fishermen have suffered. In other parts of the world, some catfish do have extremely toxic venoms that can be deadly to humans. Researchers have focused a great deal of attention of venom produced by snakes and spiders, but venomous fish had been largely neglected, said Wright, who used histological and toxicological techniques, as well as prior studies of evolutionary relationships among catfish species, to catalog the presence of venom glands and investigate their biological effects. Catfish venom glands are found alongside sharp, bony spines on the edges of the dorsal and pectoral fins, and these spines can be locked into place when the catfish is threatened. When a spine jabs a potential predator, the membrane surrounding the venom gland cells is torn, releasing venom into the wound. In his paper, Wright describes how catfish venoms poison nerves and break down red blood cells, producing such effects as severe pain, reduced blood flow, muscle spasms and respiratory distress. However, because none of the species he examined produces more than three distinct toxins in its venom, each species probably displays only a subset of the whole repertoire of effects......... Tropical birds waited for land crossing
This red-legged honeycreeper dispersed from South America into North America over the completed land bridge - Photo by Noel Ureña, copyright by Tropical Feathers www.costaricabirdingtours.com
"While a number of North American birds simply flew across the marine barriers that once separated the continents, tropical birds, particularly those in Amazon forest regions, began colonization of North America almost entirely after the completion of the land bridge," says main author Jason Weir, who conducted the study as part of his PhD at UBC. "This study is the most extensive evidence to date that shows the land bridge playing a key role in the interchange of bird species between North and South America and the abundant biodiversity in the tropical regions," says Weir, now a post-doctoral fellow at the University of Chicago. The Isthmus of Panama land bridge was completed between three and four million years ago, and today consists of the country of Panama. It is believed to have initiated the Great American Biotic Interchange, bringing mammals that evolved uniquely in South America during its "island isolation" - the armadillo, opossum and porcupine - to North America. Fossil records have shown that mammalian species also travelled across the land bridge from North to South America, increasing biodiversity in the tropical regions. "But a lack of bird fossils has made it difficult to determine if the land bridge was equally instrumental in the interchange of avian species," says Weir......... Population status of white marlin
Given considerable concern about its declining populations, petitions to list the white marlin under the U.S. Endangered Species Act were considered in 2002 and 2007. Listing the fish would have undoubtedly put an end to white marlin fishing tournaments, which infuse millions of dollars into the recreational fishing industry as well as local economies......... The Pitch of Blue Whale Songs is Declining
The Pitch of Blue Whale Songs is Declining Around the World, Scientists Discover
Researchers' theory: An increase in population size may mean sounds used in mate competition need not travel as far as before; acoustic information extracted from songs could be useful population monitoring tool Mark McDonald of WhaleAcoustics in Bellvue, Colo., along with John Hildebrand of Scripps Oceanography and Sarah Mesnick of NOAA Fisheries Southwest Fisheries Science Center studied blue whale song data from around the world and discovered a downward curve in the pitch, or frequency, of the songs. The decline was tracked in blue whales across the globe, from off the Southern California coast to the Indian and Southern Oceans. "The basic style of singing is the same, the tones are there, but the animal is shifting the frequency down over time. The more recent it is, the lower the frequency the animal is singing in, and we have observed that in every song we have data for," said Hildebrand, a professor of oceanography in the Marine Physical Laboratory at Scripps. The study's results are reported in the most recent issue of the journal Endangered Species Research. The scientists examined a list of possible causes for the frequency drop-from climate change to a rise in human-produced ocean noise-and believe it appears to be explained by the increase of blue whale numbers following bans on commercial whaling activities......... Rhino poaching surges in Asia, Africa
The trade is being driven by Asian demand for horns and is made worse by increasingly sophisticated poachers, who now are using veterinary drugs, poison, cross bows and high caliber weapons to kill rhinos, the report states. Since 2006 the majority (95 percent) of the poaching in Africa has occurred in Zimbabwe and South Africa, as per new data. "These two nations collectively form the epicentre of an unrelenting poaching crisis in southern Africa," said Tom Milliken of TRAFFIC. The report, which was submitted to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) ahead of its 15th meeting of the Conference of the Parties (CoP15) in March, documents a decline in law enforcement effectiveness and an increase in poaching intensity in Africa. The situation is most serious in Zimbabwe where rhino numbers are now declining and the conviction rate for rhino crimes in Zimbabwe is only three percent. Despite the introduction of many new measures, poaching and illicit horn trade in South Africa has also increased. "Concerted action at the highest level is needed to stop this global crisis of rampant rhino poaching," said Amanda Nickson, Director of the Species Programme at WWF International. "We call on the countries of concern to come to COP 15 in March with specific actions they have undertaken to show their commitment to stopping this poaching and protecting rhinos in the wild"......... Shark fins and their geographic origin
This is a scalloped hammerhead (Sphyrna lewini) at Cocos Island, Costa Rica.
Credit: Terry Goss 2008/Marine Photobank The U.S. has proposed that CITES list the scalloped hammerhead and five other shark species under the organization's Appendix II, which would require permits for, and monitoring of, all trade in these species across international boundaries. Knowing the species and geographic origin of fins being traded would allow management and enforcement efforts to be allocated more effectively......... Decline in Siberian tiger population
This is a Siberian tiger photographed in the Russian Far East. A new report released today shows a dramatic decline in Russian tigers due to poaching and habitat loss.
Credit: Dale Miquelle/Wildlife Conservation Society WCS says the report will help inform Russian officials of what needs to be done to protect remaining populations of the world's biggest cat. The report was released by the Siberian Tiger Monitoring Program, which is coordinated by WCS in association with Russian governmental and non-governmental organizations. It revealed that a recent tiger survey over a representative part of the tiger's range showed a 40 percent decline in numbers from a 12-year average. Annual tiger surveys are conducted at 16 monitoring sites scattered across tiger range to act as an early warning system to detect changes in the tiger population. The monitoring area, which covers 9,000 square miles (23,555 square kilometers), represents 15-18 percent of the existing tiger habitat in Russia. Only 56 tigers were counted at these monitoring sites. Deep snows this past winter may have forced tigers to reduce the amount they traveled, making them less detectable, but the report notes a 4-year trend of decreasing numbers of tigers......... |
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