Blue Whale Song Mystery Baffles Scientists

All around the world, blue whales aren’t singing like they used to, and scientists have no idea why. The largest animals on Earth are singing in ever-deeper voices every year. Among the suggested explanations are ocean noise pollution, changing population dynamics and new mating strategies. But none of them is entirely convincing.

Scientists first noticed the change eight years ago, when they kept needing to recalibrate the automated song detectors used to track blue whales off the California coast. The detectors are triggered by songs that match a particular waveform. Their analysis shows that the songs’ tonal frequency is falling every year by a few fractions of a hertz. There seem to distinct populations of whales in different oceans, yet they’re all showing this common shift.
Because only male blue whales sing, the answer may involve mate choice and sexual selection. The researchers hypothesize that as larger, ostensibly more virile whales tend to produce deeper songs, other males may be trying to emulate them, just as human guys might lower their voices when trying to impress a woman.

Scientists note that whale songs are a cultural affair. Humpback whales are known to learn from each other, and whales have extraordinarily large and complex brains. They appear to share many social and cognitive traits with people.

Read more at the original article here.

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?

Click picture to see bigger version:

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.

Stem Cells from Fat Used to Grow Teen's Missing Facial Bones

Surgeons have reported success in first human bone growth procedure using fat stem cells.

Stem cells so far have been used to mend tissues ranging from damaged hearts to collapsed tracheas. Now the multifaceted cells have proved successful at regrowing bone in humans. In the first procedure of its kind, doctors replaced a 14-year-old boy's missing cheekbones—in part by repurposing stem cells from his own body.

The technique, should it be approved for widespread use, could benefit some seven million people in the U.S. who need more bone—everyone from cancer patients to injured war veterans.

Read more in the original article here.

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Fossils Push Back Earliest Complex Animals 40 Million Years

A series of fossils unearthed in southwestern China has revealed the origins of complex life in unprecedented detail, and pushed its beginning back by at least 40 million years.

The specimens come from the Doushantuo formation, a layer of sediments deposited about 590 million years ago, just before the Ediacaran period’s primordial fauna gave way to the complex creatures of the Cambrian explosion.

During the Ediacaran, even the most structurally complicated animals had flat bodies with simple symmetry, like living quilts or mattresses. It was only during the Cambrian that animals developed what’s known as bilateral symmetry — a distinct front and back, top and bottom.

The Doushantuo fossils date to the cusp of this transition, and are so finely preserved that scientists can distinguish the structures of individual cells. The latest fossils aren’t even fully formed animals, but embryos.

Using synchrotron radiation microtomography — a microscopy technique that combines thousands of of X-rays taken from different angles — researchers reconstructed the embryos in three-dimensional detail. They found that the embryos were bilaterally symmetrical, and were organized so differently that they belonged to two distinct taxonomic groups. For those groups to be so different, bilateral symmetry must have been around for a while.

Original article here.

Giant Orb Spider Discovered

Scientists have found the world’s largest species of golden orb-weaver spider in the tropics of Africa and Madagascar. The discovery marks the first identification of a new Nephila spider since 1879.

Females of the new species, Nephila komaci, measure 4 to 5 inches in diameter, while the male spiders stay petite at less than a quarter of their mate’s size. So far, only a handful of these enormous arachnids have been found in the world. Its only definite habitat is a sand forest in Tembe Elephant Park in KwaZulu-Natal.

Like all Nephila spiders, females of the new species spin huge webs of golden silk, often more than 3 feet in diameter. In the report of the discovery of this rare spider, the researchers also addressed the evolution of the dramatic size difference between male and female orb-weavers.

By mapping out the evolutionary tree of all known orb-weaver species, the scientists discovered that as the spiders evolved, females got bigger and bigger, while males stayed roughly the same size.

It is good for females to be big, because they can lay so many more eggs. In addition, large size probably helps females avoid being eaten by predators. Males, on the other hand, are better off staying small and reaching sexual maturity at a young age. Because males spend most of their time underground, hunting for a mate is one of the most dangerous activities they undertake.

Original article here.

Satanic Leaf Tailed Gecko

Yes, that is what it is called!

The Uroplatus phantasticus is a species of gecko endemic to the island of Madagascar. The satanic leaf tailed gecko is also commonly known as the eyelash leaf tailed gecko or fantastic leaf tailed gecko.

These geckos are an arboreal species relying on their natural camouflage as they dwell among the leaves and leaf litter of the northern and central tropical forests of Madagascar.

DNA Replication Video

Below is a clip from a PBS production called "DNA: The Secret of Life." It details the latest research (as of 2005) concerning the process of DNA replication.

Microscope Photography

The pictures below were taken from a microscope photography gallery and represent current and past winners from Nikon’s annual Small World photomicrography competition.

Male sex organ of a flowering plant:



Mouse embryo:



Mouse colon:



House fly:



Rat cerebellum:



Fresh water rotifer feeding among debris:



Mangrove leaf:



Clink the link here to see additional examlpes of photomicrography.

Jaw bone created from stem cells

Scientists have created part of the jaw joint in the lab using human adult stem cells. They say it is the first time a complex, anatomically-sized bone has been accurately created in this way.

It is hoped the technique could be used not only to treat disorders of the specific joint, but more widely to correct problems with other bones too.

The bone which has been created in the lab is known as the temporomandibular joint (TMJ).

The latest study used human stem cells taken from bone marrow. These were seeded into a tissue scaffold, formed into the precise shape of the human jaw bone by using digital images from a patient.

The cells were then cultured using a specially-designed bioreactor which was able to infuse the growing tissue with exactly the level of nutrients found during natural bone development.

Original article here.

Infrared Video of 500,000 Bats Emerging From Cave

Bats use echolocation to see in the dark, but unfortunately human scientists cannot do the same.

That poses a problem for ecologists who want to know, for example, how many Brazilian free-tailed bats live in the Carlsbad Caverns of New Mexico. Researchers can’t shine a light on them because that disrupts their behavior, but they can’t see them without light. The answer? Infrared cameras.

By installing infrared sensors, scientists were able to study the bat colonies in great detail from less than 50 feet away. The above video shows the infrared camera capturing a half million bats emerging from the cave to feed at night.

Original article here.

Glow-in-the-Dark Mushrooms Discovered

Scientists have announced the discovery of several species of glow-in-the-dark mushrooms. The findings increase the number of aglow mushroom species from 64 to 71, shedding light on the evolution of luminescence in nature.

The newly identified mushrooms, which emit a bright, yellowish-green light 24 hours a day, were found in Belize, Brazil, Dominican Republic, Jamaica, Japan, Malaysia and Puerto Rico. They include four species new to science and three new reports of luminescence in known species.

Three quarters of glowing mushrooms, including the newly identified species, belong to the Mycena genus, a group of mushrooms that feed off and decompose organic matter.

As for why the mushrooms glow, one scientists speculates that some fungi glow to lure in nocturnal animals that aid in the dispersal of the mushroom's spores, which are similar to seeds and are capable of growing into new organisms. Fungi, along with plants, animals and protists are considered eukaryotes by biologists, meaning "true kernel," due to the packaging of the genome into the membrane-bounded compartment called the nucleus. (Simple bacteria and archaea, which lack a cell nucleus, are considered prokaryotes.)

Original article here.

Million to one apple is half red, half green

A fruit grower was left stunned when he found a golden delicious apple on his tree split exactly half green, half red down the middle. The fruit's coloring is thought to be caused by a random genetic mutation at odds of more than a million to one.

Experts believe that the odds of finding an apple with such a perfect line between the green and the red are more than a million to one. In such cases, the red side usually tastes sweeter than the green side – because it has seen more sunshine during its growth.

Scientists note that this is known as a chimera where one of the first two cells has developed differently giving rise to one half of the apple being different. It is unlikely to be a stable mutation but it is worth checking next year to see if it recurs. There are instances of some striped apples and pears where the mutation remains stable.

Original article here.

Side note: This is the 300th post to the blog!

Butterflies Use Antenna GPS to Guide Migration

Scientists have finally located the 24-hour clock that guides the migration of monarch butterflies. Instead of being in the brain where most people expected, it turns out the circadian clock is located in the butterflies’ antennae.

Every fall, monarchs make an impressive 2,000-mile trek south, using the sun to guide them to the exact same wintering spot in central Mexico. But because the sun is a moving target, changing position throughout the day, biologists have long speculated that in addition to having a “sun compass” in their brains, butterflies must use some kind of 24-hour clock to guide their migration. Now, researchers have located this special GPS system.

The scientists had been studying the ability of butterfly antenna to sense odors when they uncovered something surprising: When they clipped off the insects’ antennae and tethered them in a flight simulator, the butterflies no longer flew in a uniform direction. Without their feelers, the butterflies lost the ability to navigate using the sun, as if they could no longer adjust their direction based on the time of day. This raised the prospect that the timing mechanism may actually be in the antennae.

The researchers tested their hypothesis by painting the antennae of half their butterflies with black enamel, which blocked all input from the sun, and the other half with clear paint that allowed the sun’s rays through. While the monarchs covered with clear paint kept flying south, the butterflies with blacked-out antennae started to drift consistently north, suggesting that their molecular clock was running about an hour off schedule.

The new finding not only changes how scientists think about butterfly antennae, but may also suggest a similar role for an antennal clock in other types of insects, such as bees and ants, that also operate elaborate navigation systems. Like butterflies, honeybees use a sun compass to find flowers and communicate their specific position to the rest of the hive, and they could be using a circadian clock in their antenna to adjust the sun’s position to the time of day.

Original article here.

Strange Animals Bred for Business Purposes

Breeders around the world covet certain animals for their economic potential. Some produce a lot of meat. Some are iridescent. Others fit well into small spaces. All of the animals featured below have highly unusual attributes that make each a potentially lucrative business proposition:

Giant Guinea Pig

Cuy meat is lean, protein-packed, and versatile. Cuys, or guinea pigs, reproduce quickly, offering a steady supply of meat. One Lima, Peru official said that guinea pigs will feed a family of up to eight people for only USD $3.20. Peruvians eat about 65 million guinea pigs per year. Scientists in Peru supersized the guinea pig, introducing a giant guy weighing about 2.2 pounds, twice the usual size.



Belgian Blue

Known as the Incredible Hulk cow, Monster cow, and Schwarzenegger cow, the Belgian Blue takes the world’s blue ribbon for buffness. The cow’s hereditary myostatin defect results in excessive muscle growth known as “double muscling.” As a result, the breed produces a large amount of lean beef.



Fainting Goat

Fainting goats are bred to fall over. A hereditary disorder, myotonia congenita, causes their muscles to freeze when they’re scared, often resulting in them collapsing on their sides. Their small size makes them ideal for small farms, where they won’t hop fences—or will scare themselves into collapsing when they try. According to oral history, the fainting goat was a good asset protector. Handlers would keep them with other (more valuable) animals, like sheep. When a predator came around, the fainting goat would collapse, effectively sacrificing itself so that the other animals could safely run away.



German Giant

The German Giant, one of the biggest domestic rabbit breeds on Earth, can grow to the size of a dog. Breeders covet giant rabbits for their looks, their fur, and their meat.



Minicow

German Shepherd-sized minicows cost only a few hundred dollars. They are tiny, meaty and fit in your backyard. Homesteaders can choose from Irish Dexter, Mini Hereford, or Lowline Angus cows.



Jersey Giant

The Jersey Giant chicken was originally bred as a replacement for turkey. The breed, originally crossbred from three other kinds of chickens, produces hens weighing an average of 11 lbs, and cocks of 13 lbs. The meat industry initially took to the idea, but then cast Jersey Giants aside because they don’t grow fast enough.



GloFish

Genetically engineered GloFish come in a variety of colors, such as Sunburst Orange, Starfire Red and Electric Green. These colorful zebrafish are the world’s first genetically modified pet. In 1999, scientists inserted fluorescence proteins from coral and jellyfish into a zebrafish embryo, resulting in the GloFish’s luminescent qualities. The idea was to create a fish that would fluoresce when it came near toxins, allowing it to detect pollution. When businesspeople caught wind of the glowing fish, they saw great potential for consumer sales.



Original article here

Spider-Man lookalike lizard

The vivid red-and-blue coloring of the Mwanza Flat-headed Rock Agama is almost uncannily like that of Spiderman, and comic book fans have been flocking to exotic pet shops to snap them up.

Agamas make good pets as they become tame and docile if handled regularly. They can grow up to a foot long with a balanced diet of locusts, crickets, mealworms and waxworms.

Native to Kenya, the rock agama is unable to throw webs, but can change color – the brightly colored males will change brown at night or if frightened. They can also run on their hind legs can scale vertical walls like Spider-man.

Original article here.

UPDATE:
More pictures of the lizard can be seen here.

Gene Therapy Cures Color-Blind Monkeys

After receiving injections of genes that produce color-detecting proteins, two color-blind monkeys have seen red and green for the first time.

Except in its extreme forms, color blindness isn’t a debilitating condition, but it’s a convenient stand-in for other types of blindness that might be treated with gene therapy. The monkey success raises the possibility of reversing those diseases, in a manner that most scientists considered impossible.

The team injected their monkeys’ eyes with viruses carrying a gene that makes L-opsin, one of three proteins released when color-detecting cone cells are hit by different wavelengths of light. Male squirrel monkeys naturally lack the L-opsin gene; like people who share their condition, they’re unable to distinguish between red and green.

At first, the two monkeys behaved no differently than before. Though quick to earn a grape juice reward by picking out blue and yellow dots from a background of gray dots on a computer screen, they banged the screen randomly when presented with green or red dots.

But after five months, something clicked. The monkeys picked out red and green, again and again. At the biological level, scientists can’t say precisely what happened — the monkeys, named Sam and Dalton, are alive and healthy, their brains unscanned and undissected — but their actions left no doubt.

Read more about the implications of the findings here.

How to make a Band-Aid from Tree Fungus

If you're out in the wilderness without a first aid kit and need a band-aid, according to this tutorial you can make one out of birch tree fungus in a pinch.

The author notes that Birch polypore, also known as Piptoporus betulinus, makes a for a good emergency band-aid. Check out the link for details on how to properly identify the fungus needed and pointers on avoiding additional injuries while making the band-aid.

Original article here.