cafecuriosity

As Different As Cats and Dogs

Time for a confession. while I quite like dogs - particularly big boofy dogs, I'm basically a cat person. For years I put that foible down to cats like independence and general insouciance. Thanks to the U.s. National Science Foundation and some ex-Duke dudes, I realize its really because cats are curious and creep up on objects of interest. According to the study; 'Dogs Chase Efficiently, But Cats Skulk Counterintuitively', cast have just trashed the assumption by biologists that natural selection is all about energy efficiency. Here I was admiring my cats' ability to sleep 20 hours a day (2 hours play, 2 hours snacking) when in reality they were following their evolutionary path to success! While dogs are all balanced if bouncy kinetic energy, cats have traded off efficiency in exchange for the ability to slink along before pouncing on an unsuspecting cloth mouse and give it a good pummeling. Dogs like humans, have a gait that reduces their muscular workload by 70% while your cat manage only 37% at best. This explains why cats operate in short bursts and need so much sleep to recharge the batteries - here I was putting it down to pure laziness!  So te next time your feline has their paws up, remember they're only skulking counterintuitively! http://news.duke.edu/2008/12/catwalk.html   Image: Seti demonstrating counterintuitive skulking!, David Rymer, 2008

Window On A Green Sahara

Much of the commentary on the booming Gulf economies centers on speculation of how sustainable it all is. Just how precarious human existence can be, was illustrated last month when National Geographic published details of its spectacular discovery of the largest Stone Age graveyard yet found in the Sahara. The site named Gabero lies in Niger, beside a dried out lake and dates back over 10,000 years. It contains the remains of two very different civilizations - the Kiffian and the Tenerian, cultures separated by more than 1,000 years. Over two hundred graves were found, together with stone tools, beads, harpoon points, fishhooks and potsherds and skeletons of elephants, giraffes, warthogs, pythons, crocodiles, hartebeests and the imposing 6 foot long Nile perch. Now the Sahara has been desert for quite some time, so how did a lake suddenly appear in the Tuareg's Tenere Desert? Twelve thousand years ago, the Earth's orbit wobbled slightly, shifting Africa's wet season north. Rain and floods caused the desert to bloom. Lakes formed, attracting the Kiffian, animals and fish. The wobble eventually smoothed itself out returning the Tenere's arid climate, before repeating itself rather less vigorously 1,000 years later, enabling the Tenere to eke a living from the region's shallower lakes. Whether historically high oil prices will prove to be the Emirates equivalent of the orbital 'wobble' remains to be seen. History however is replete with desert civilizations which bloomed before being swallowed once more by the desert's shifting sands.

PS. The graveyard was discovered by accident by members of an expedition hunting serendipity headed by University of Chicago Professor Paul Sereno!  http://news.nationalgeographic.com/news/2008/08/080814-sereno-sahara-missions.html  Image: Expedition highlight, the stunning triple burial comprising a woman entangled with two children, National Geographic

Oops It Was Us (47,000 Years Ago)

It is amazing how serendipity can re-shape scientific theory. After decades of arguing over whether human hunting or climate change was responsible for driving the world's megafawna into extinction, one island bobbed literally in the eye of the hurricane. Tasmania once boasted a thriving zoo of marsupials resembling; leopards, rhinos, ground sloths, and a brace of short and long-faced kangaroos that browsed the lush vegetation like antelopes. Humans had been absolved of culpability for their demise mainly because the megafawna was thought to have died out before hunters were able to cross the land bridge from mainland Australia (approx 43,000 years ago). No longer! A group of cavers exploring a network of caves under Mt Cripps in north-west Tasmania stumbled serendipitously over skeletons of Tasmania's megafawna species. Alas, these remains showed some species were wandering Tasmania's misty forests 2,000 years after human hunters found their way onto the island. Given the climate was relatively stable around that time, human over-hunting has been fingered for their demise. 

PS. It's all Darwin's fault! Ever since Darwin discovered the remains of giant sloths in South America in the 1830's, debate has raged over whether human hunting or climate change was the driving force behind the mass extinctions.

http://www.exeter.ac.uk/news/newsprehistoric.shtml   Image: 1. Artist's reconstruction of Palorchestes azael, a ground sloth like marsupial weighing 500 kg, University of Exeter, 2. Skull of Palorchestes azael, University of Exeter 

Culling Skippy

Few issues propel Australian into the international news spotlight as a headline describing a kangaroo cull. Skippy has many global supporters who see any culling activity as unacceptable. So, the decision to cull 400 of the nearly 600 eastern grey kangaroos resident residing on two Australian Defence Force bases outside Canberra proved particularly controversial. The worst drought to afflict Australia in over a century has left the once flourishing grasslands inside the military bases parched and denuded of grass cover. While passions run deep on both side of the cull debate, few consider the collateral damage inflicted on other species by the combined effects of drought and high kangaroo numbers. Tympanocrytis pinguicolla or the grassland earless dragon is one of the world's rarest reptiles and for while in the 1990's was considered extinct. It was only rediscovered when Dr Will Osborne a biologist with the University of Canberra's Institute for Applied Ecology accidentally rolled a rock over with his foot while bushwalking. Underneath that rock was the first Tympanocrytis pinguicolla seen for thirty years!  The lizards depend on insects for food which in turn feed off grass and vegetation. Over-grazing by local sheep, cattle and kangaroos threatens not only the health of the kangaroos themselves but triggers a crisis across the entire food chain. Ironically, the need for constant water supplies for stock and agriculture has given the kangaroos a get out of jail card. Those that previously would have died during severe drought limp on weakened but still able to compete for scare grazing, making the culling decision harder still unless you happen to be a Tympanocrytis pinguicolla!

http://www.ufz.de/index.php?en=12252   Image: 1. Military base outside Canberra, Australia, Anett Richter/UFZ, 2. Grassland Earless Dragon, Tympanocrytis pinguicolla, Tilo Arnhold/UFZ

Creature Feature #10

There's a reason they call them wild animals! The Javan Rhino is usually extremely shy and retiring, posing quite a challenge for researchers trying to monitor them. Video traps are proving to be an increasingly popular solution. It doesn't stress the animal and requires little training or resources to set up and service. The video cameras use infra-red to avoid scaring the animals when activated. At least that's the theory. One rhino mother however took exception and charged the video camera. Round 1 to the rhino! The now shop soiled video camera was re-mounted on its stand the next day and has been happily filming away.

Frank Gallagher, the retired mail supervisor at The Academy of Natural Sciences received his 15 minutes of fame this month when ichthyologist Dr. Mark Sabaj Perez named a new species of catfish (Rhinodoras gallagheri) after him. Known as the Orinoco thicklip catfish, its a shy thing, hiding during the day and hunting for aquatic insects at night. Now, Rhinodoras gallagheri wasn't discovered as such by some intrepid explorer fishing the Orinoco's exotic waterways. No, Perez was looking through the Academy's collection of 1.3 million fish when he noticed two specimens collected in Venezuala in 1989 were different from the rest! Frank's response to his serendipitous honour was classy, "I thought it was nice of him" he said.

Ah, the power! From a humble postman to rock and roll legend, the species name game knows few boundaries as a biology professor from East Carolina University discovered. Jason Bond is a self-confessed Neil Young freak, so it seemed natural to name a new species of trapdoor spider after him.Bond pickeup $750,000 in grants to classify the trapdoor species for the National Science Foundation's 'Tree of Life' project. Myrmekiaphila neilyoungi now takes its place in biology's pantheon!

Who said scientists lack entrepreneurial skills? When Florida Museum of Natural History researchers George Austin and Andrew Warren discovered a new species of owl butterfly (named after the eyespots on its wings!) they put the naming rights up for auction online. An anonymous donor kicked in $40,800 to name the new species Opsiphanes blythekitzmillerae or the Minerva owl butterfly after Margery Minerva Blyth Kitzmiller of Ohio. Minerva is the first new owl butterfly to be discovered in 100 years. It has a unique wing shape and translucent wing scales. Like similar discoveries, Austin found Opsiphanes blythekitzmillerae while curating the McGuire center's 6 million Lepidoptera specimens! 

http://www.worldwildlife.org/who/media/press/2008/WWFPresitem9174.html   http://www.ansp.org/press/release/Fish_named_for_mailman_6-08.pdf    http://www.ecu.edu/cs-admin/news/releases/2008/5/05082008ecubondneilyoungspider.cfm   http://news.ufl.edu/2007/11/21/butterfly-name/   Image: 1. Javanese rhino with calf, WWF Indonesia, 2. Rhinodoras gallagheri, Mark Sabaj/ANSP, 3. Myrmekiaphila neilyoungi, UCU News Services, 4. Opsiphanes blythekitzmillerae, Priscilla Brodkin

Weird Ring Serendipitously Stumbled Upon

Quote of the week surely goes to NASA Spitzer Science Center's Stefanie Wachter when she observed, "The universe is a big place and weird things can happen." Wachter was referring to her serendipitous discovery of a ring of material surrounding the magnetic corpse of a massive dead star (magnetar) seductively named SGR-1900+14. Trawling through Spitzer's archived data - a dull job at any time, Wachter happened to notice the odd ring formation around the magnetar. Believed to have formed in 1998, when the surface of the magnetar cracked, emitting an energy blast that blew out a nearby dust cloud, creating a cavity around SGR-1900+14 which was subsequently lit up by a surrounding cluster of stars. This type of ring has never been seen before but as Wachter's theory goes, if there is one out there, there might be more and someone has to find them! 

http://www.jpl.nasa.gov/news/news.cfm?release=2008-086   Image: Ghostly ring 7 light years across around a massive dead star, NASA/JPL-Caltech

Engineering Our Future

Size of often the engineers enemy, particularly in the emerging 'wireless body area network' biosensor technology sector. Too big and the sensors are uncomfortable to wear, too small and the sensors lack adequate battery life or signal strength. Engineers at Queen's University Belfast have developed a new antenna that skirts these obstacles. The technology exploits the 'creeping wave' effect. When a signal is broadcast from an on-body sensor, most of the signal strength is either absorbed by the body or radiated outwards. The remainder (the creeping wave) hugs the surface of the skin. The novel antenna is 50 times more efficient than its predecessors, allowing its thickness to drop from 34mm to under 5mm. The signal is simply transmitted to a control unit on the body, where it can be accessed by doctors over the internet or by mobile phone!

Serendipity made it into space in April when a Finnish design for a solar wind sail went from design to prototype. Born from the Finnish Meteorological Institute's research into how the solar wind interacts with the planets and their atmosphere, the design might just revolutionize space exploration. The solar sail traps the continuous gentle pressure of the solar wind to provide thrust. The design features long metallic tethers and a solar powered electron gun to maintain the tethers positive charged, maintaining the sail's shape. Prototyping the new solar sail hinged on successfully developing a new technique for ultrasonic welding to bond the thin metal wire comprising micrometeoroid-resistant tethers.

http://www.eurekalert.org/pub_releases/2008-05/eaps-iam051408.php   http://www.fmi.fi/news/index.html?Id=1208243495.html   Image: 1. Wearable antennas being tested, Engineering and Physical Sciences research Council, 2. Electric sail design, Antonin Halas, Finnish Meteorological Institute

Serendipity Locates Ancient Alexandria

Alexander the Great usually scores the public kudos for founding the Egyptian city of Alexandria around 331 BC. However, archaeologists acknowledge the city of Rhakotis was there before Alexander rode into town. Now Jean-Daniel Stanley a geoarchaeologist specialising in Nile delta sedimentation and its impact on subsidence and sea level rise has produced definitive proof that Rhakotis preceded Alexander by 700 years!

Stanley sank a series of core samples into Alexandria harbour in 2001 in an effort to understand how Greek and Roman Alexandria came to be underwater. Those core samples produced some unexpected results. Firstly, up popped igneous rock pebbles. These rocks originated far upriver in Middle and Upper Egyptian quarries and were not brought down by the Nile. Next, pottery fragments dating back to 940 BC surfaced. These were shown to be locally fired and typical of pottery in the region around that time, rather than having been imported. Final confirmation came in the form of rising lead levels in the sediments prior to Alexander's arrival. The Greeks used a lot lead in their cities.

There Stanley had it, radiocarbon dates, pottery shards and increased concentrations of lead - all indicating habitation long before Alexander founded his city! This was the first hard evidence that Rhakotis was more than just a fishing village which had struggled along for centuries.

http://www.si.edu/opa/InsideResearch/articles/V19_Alexandria.html   Image: 1. Diver encounters a stone sculpture of the god Hapi while surveying Alexandria's harbour, Smithsonian 2. Preparing to drill a core sample in Alexandria harbour, Juan Daniel Stanley, 3. Artists impression of Alexandria 2,000 years ago, IEASM team in Bernard and Goddio

A Nose for Navigation

Scientists have long believed birds used the Earth's weak magnetic field as a navigation aid during their long annual migrations. However until last month, quite how they managed this prodigious feat remained a mystery. Typically, serendipity played a role. Ten years ago, a research team at Arizona State was inspired by the ability of plants to orient themselves to maximise their exposure to sunlight for photosynthesis. They synthesized a molecular "triad" which was influenced by weak magnetic fields when it was exposed to sunlight. A related triad was synthesised and proved to be sensitive to both the magnitude and direction of even weak magnetic fields such as the Earth's. It was a form of magnetic compass. This was the first time a chemical megnetoreception mechanism based on sensitive chemical reactions to Earth's geomagnetic field had been shown to be viable. It also illustrates the potential for power lines and communications equipment to mess about with the magnetic compass of migrating birds. 

However as Luke Naismith observed, "That still doesn't explain how birds from thousands of kilometers away know when Lake Eyre in central Australia has water in it." No pleasing some birders is there!

http://asunews.asu.edu/20080430_birdnavigation  Image: 1. Bird Navigation Chemical Model, Zina Deretsky, National Science Foundation, 2. Lake Eyre in flood, www.ivanhoe.hotkey.net.au

Serendipity Captured On Camera

One of the richest sources of serendipitous discovery are field biologists who often stumble across rare species while looking for something far commoner. Katie Moriarty agrad student at Oregon State University was researching the effects of landscape change on American martens (a slender, agile relative of minks, weasels and wolverines) at the Tahoe National Forest. Katie's study deployed a large array of remotely activated cameras using motion sensors and heat detectors. While she caught a few martens, together with black bears, coyotes, bobcats, ravens, spotted skunks, Stellar's jay, mice and weasels, one animal proved to be a show stopper. Caught from the rear (never its best angle), was a California wolverine (Gulgo gulgo). Why the fuss? Well, the last sighting of a Californian wolverine was in the 1920's and they are supposed to be extinct. The nearest know population lies 900 miles north in Washington State

http://oregonstate.edu/dept/ncs/newsarch/2008/Mar08/wolverine.html   Image: 1. Californian wolverine, Katie Moriarty 2. Wolverine, Wikipedia