Raptor Talons

The pictures below are from a recent study on raptor talons. For a summary of the findings, read the article here. The talons below are from the following: (A) goshawk (B) red-tailed hawk (C) peregrine falcon (D) great grey owl (E) osprey.

Puppy vs. Praying Mantis: Who Wins this Smackdown?

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Turtle Completes the Impossible

World's Weirdest Worms

Five years after discovering some of the strangest creatures in the world — mouthless worms that live in the bones of dead whales — scientists have taken a peek into their genes. Though not complete, the glimpse shows these creatures to be far more complicated than was known.

The worms, found in a gray whale skeleton off the coast of California, prompted scientists to designate them as representatives of an entirely new genus, dubbed Osedax. They belonged to a taxonomic family of marine worms that lack mouths and anuses, and rely entirely on bacteria to absorb and excrete nutrients. But Osedax was unique: Adult males were extremely small, and lived in colonies inside the females. Even more strikingly, they occupied an evolutionary niche comprised entirely of fallen whales.

Scientists note that anything below 1000 meters is fed entirely by ‘marine snow’ — the things that are supported by photosynthesis at the top of the ocean, and the things that eat them, and eventually fall to the ocean floor.

Since the original discovery, other species have been found in whalebones off the coast of Sweden and Japan. A total of five species have now been named, enough for a comparison of their genetic characteristics to provide insight into their evolutionary history. The analysis suggested at least 12 more as-yet-unidentified lineages of Osedax. The worms might still be out there, though some may have gone extinct.

Since whale carcasses are hard to come by, researches have been able to study the worms by luring them with carcasses of other animals. They can live perfectly happily on cow bones, and researchers have also put down sea lion bones and pig bones.

You can see an ocean-floor webcam here, where researchers recently sank a pig.

Original article here.

Birds Use Light, Not Magnetic Field, to Migrate

In European robins, a visual center in the brain and light-sensing cells in the eye — not magnetic sensing cells in the beak — allow the songbirds to sense which direction is north and migrate correctly, according to a new study in Nature. The study may improve conservation efforts for migratory birds.

Researchers have known that built-in biological compasses tell migrating birds which way to fly, but the details of how birds detect magnetic fields has been unclear.

Some researchers had proposed that iron-based receptors in cells found in the upper beaks of some migratory birds sense the magnetic field and send that information along a nerve to the brain. Other scientists favor the hypothesis that light-sensing cells in birds’ eyes sense the magnetic field and send the information along a different route to a light-processing part of the brain called cluster N.

To find the location that houses the magnetic compass, scientists caught 36 migratory European robins and made sure that the birds could all orient correctly under natural and induced magnetic fields. Next, the researchers performed surgeries on the birds to deactivate one of the two systems. The team either severed the nerve that connects the beak cells to the brain, or damaged the brain cells in cluster N that receive light signals from cells in the eye.

Birds with the severed beak-to-brain nerve — called the trigeminal nerve — still oriented perfectly, suggesting that the beak cells are not important for orientation. On the other hand, birds with damaged cluster N regions could no longer sense and orient to magnetic fields. These robins failed to pick up both the Earth’s natural magnetic field and the artificial fields created by the researchers.

Understanding more about how birds navigate and sense the environment may have important conservation implications. Migratory birds that humans have relocated often fly back to the original migratory grounds. But if researchers can figure out how the birds navigate, conservationists may be able to trick the birds into staying where it’s safe.

Original article here.

The Spider Awards: Arachnid Hall of Fame

Below are several examples of spiders from Wired's Spider Awards: Arachnid Hall of Fame. Read the article to learn more about the various species. Example "awards" for spiders include: largest, smallest, deadliest, cutest, nicest, sneakiest, weirdest, snobbiest, cuddliest and busiest.



















Original article here.