Insects Emit Universal Death Stench

Scientists have discovered that insects from cockroaches to caterpillars all emit the same stinky blend of fatty acids when they die, and this sinister stench sends bugs of all kinds running for their lives.

A biologist made this morbid discovery while studying the social behavior of cockroaches. When a roach locates a great new abode (like your kitchen cupboard), it gives off a chemical signal to attract its cockroach friends. To determine the chemical composition of these pheromones, the scientists and his team started crushing dead cockroaches and spreading around their body juice. Cockroaches avoided places treated with these extracts "like the plague."

The team found that their concoction repelled not just cockroaches, but ants, caterpillars, woodlice and pill bugs. And even though they’re technically crustaceans rather than insects, dead woodlice and pill bugs produced the same set of fatty acids as the other animals.

Insects and crustaceans diverged from each other 400 million years ago, so the researchers think their death mix represents a universal, ancient warning signal. Recognizing and avoiding the dead could reduce the chances of catching the disease.

The scientists hope the right concoction of death smells might protect crops against pesky invaders. For instance, a log treated with the fatty acids repelled wood beetles in a forest for a full month.

Original article here.

See-Through Glass Frog

The see-through skin of an inch-long glass frog reveals her eggs. Native to Venezuela, the frogs lay eggs in bushes and trees overhanging streams. Tadpoles hatch, then tumble into the current to be swept away.



Taken from gallery here.

How to Photograph a Bat

Bats fly very quickly and only at night. Taking pictures of them is therefore very difficult. Check out the pictures below to see what steps this photographer took to get these great shots:

High-Speed Video of Locusts Could Help Make Better Flying Robots

A new study may inspire aeronautical engineers to be more "flexible" with their designs. The study shows that the bends and twists in locusts’ flexible, flapping wings power the insects’ extraordinary long-distance flights.

Even though researchers have been studying how insects and other creatures fly for a long time, the aerodynamics and architectures of wings is still not fully understood. The new work uncovers the flight signatures of flapping, flexible wings.

The research focuses on the flight of the pestilent locust, an insect renowned for its efficient flying style. The four-winged insects are built to fly hundreds of miles at a time.

Researchers used high-speed cameras to capture the details of how wings of the locust Schistocerca gregaria deform as they flap by bending and twisting.

Data from the high-resolution flight images allowed the researchers to create a near-perfect mathematical model of how the flexible, twisting wings propel the insect through the air. With the model in hand, they could predict the shapes of the air currents around the flying locusts. Tiny packets of smoke released near a flying locust showed air swirls similar to swirls predicted by the model. Tweaks to to the model indicated that stiffening and/or straightening the wings caused flight performance to suffer.

The study provides sound experimental evidence that flexible wings add to flight performance. Figuring out the details of how locusts and other insects fly may help researchers design tiny robotic fliers (or "micro air vehicles").

The picture below shows patterns of air movement caused by a flying locust (middle and right columns) are similar to air patterns predicted by a computer simulation (left column). Air swirls beneath the locust’s wings as the wings move downward from the beginning of a stroke (top panels) to the end (bottom panels).



Original article here.

Coconut Crabs

The coconut crab is the largest land-living arthropod in the world, and is probably at the upper limit of how big terrestrial animals with exoskeletons can become in today's atmosphere. The species inhabits the coastal forest regions of many Indo-Pacific islands.

Generally nocturnal, they remain hidden during the day and emerge only on some nights to forage. The crab is known for its ability to crack coconuts with its strong pincers and eat the contents.

It is also called the robber crab or palm thief, because some coconut crabs are rumored to steal shiny items such as pots and silverware from houses and tents.

The picture below gives a good in indication of how large coconut crabs are:

Bacteria Used To Make Radioactive Metals Inert

The Lost Orphan Mine (PDF) below the Grand Canyon hasn't produced uranium since the 1960s, but radioactive residue still contaminates the area. Cleaning the region takes an expensive process that is only done in extreme cases, but a biochemistry professor is researching the use of sulfate-reducing bacteria to convert toxic radioactive metal to inert substances, a much more economical solution.

The bacteria being studied are bio-corrosives and can change the solubility of heavy metals. They can take uranium and convert it to uraninite, a nearly insoluble substance that will sink to the bottom of a lake or stream. The professor is looking into the bacteria's water cleansing ability and how long the changed material would remain inert.

The research could also be beneficial to heavy metal pollution from storage tanks and industrial waste. The bacteria are already present in more than 7,000 heavy metal contaminated sites, but they live in a specific range of oxygen and temperature, making them difficult to control.

According to the professor, knowledge of the way bacteria live in microbial communities is still in its infancy and relatively little is known about the communication systems among microbes. Researchers are investigating the bacterium's basic genetics and hope to learn how to make its interactions with metals sustainable. They have already identified a few genes that are critical to converting uranium.

Original article here.

Birds "Transform" Themselves in Preparation for Migration

As fall approaches, millions of birds across North America prepare for their migration to warmer climes. Many species fly for thousands of miles, often without stopping.

At their baseline state, migratory birds are already equipped with evolutionary tools such as hollow bones and optical compasses and lungs that provide purer oxygen than is breathed by any mammal. But when dwindling sunlight triggers their migratory physiology, they undergo many more fascinating changes.

In just a few days, their food intake rises by multiple orders of magnitude — the equivalent of having a hamburger for lunch on Monday, and 100 hamburgers on Friday. Even seed-eaters switch to insect-heavy diets rich in energy-dense polyunsaturated fats.

The fat is packed on aerodynamically, tucked in the lower back and wherever else it won’t add much drag. Some species, such as warblers, which can weigh less than an ounce but fly 2,500 miles without resting, double their body weights in preparation for the voyage.

In order to keep pace with the dietary influx, the birds’ digestive organs expand. Even the cells of their stomachs swell. But shortly before takeoff, with no more need for this extra bulk, their guts shrink back to size.

In the meantime, the birds’ pectoral muscles become thicker and denser. The pecs of the red knot, a shorebird that makes 2,000 mile-long migratory flights, swell by 40 percent.

Much of this added muscle mass will be burned for in-flight energy, but most of their fuel comes from fat. Unlike mammals, who fuel endurance exertion with protein and carbohydrates before switching — a transition felt as “hitting the wall” — birds start by burning fat, and use only the minimum of protein needed to keep their brains running. They never hit the wall.

To better turn fat to fuel, their bodies boost production of fat-metabolizing proteins. In sparrows, levels of the proteins double from their usual rates. To further feed their cells, extra oxygen-carrying hemoglobin protein is pumped into the blood, right up to the limit where it would be too thick to flow.

Some species do rest during migration, stopping for a few weeks before crossing some especially vast and barren expanse, such as the Sahara. Even in this brief time, red knots’ pectorals will shrink at first, and their legs and stomachs swell. When the birds are done eating and ready to fly again, the process will be reversed. Their hearts grow the whole time.

Read more in the original article here.

Videos Show Spread of Swine Flu

By analyzing the mutations in swine flu samples, scientists have assembled the most complete model to date of the pandemic’s birth.

Traditional modeling — the pins-on-a-map approach — relies on formal reports of a disease. Although these convey the big picture, they don’t always give a clear picture of how the disease spread.

But because flu viruses constantly pick up genetic mutations as they multiply, scientists can deduce a family tree by comparing the shared ancestry of their genomes. This helps reveal hidden information about the spatial spread of the virus.

The researchers ran 242 viral genomes, collected around the world between late March and mid-July, through algorithms that determined their most likely evolutionary path. From hundreds of trillions of possible configurations, the program arrived at the models below.

The bottom video below is newer, but doesn’t clearly show swine flu spread outside North America. The top video above is older and contains fewer data points, but gives a more complete sense of the virus’ global jumps.





Original article here.

Severed Gecko Tails Have a Mind of Their Own

Even after they’re no longer connected to a lizard brain, gecko tails can flip, jump and lunge in response to their environment — and may even be able to evade predators.

Researchers have known for centuries that some animals can voluntarily shed parts of their bodies to keep from being eaten, but few studies have looked at the behavior of disposable body parts once they’ve fallen off. Now, using high-speed video and a technique called electromyography, scientists have discovered that severed gecko tails exhibit complex behavior and even seem to react to environmental cues.

They expected a series of rhythmic movements that would slow down over time, but they found, that the tail would flip left-right-left-right for awhile, and then do a jump, pivot around, and do another flip, etc.

The scientists say that figuring out what controls the jumping gecko tail may help us understand why the paralyzed muscles of spinal cord injured patients sometimes exhibit spontaneous muscle contractions, which they hope could someday lead to treatments that restore some control over such movements.

After attaching electrodes to the tails of four adult leopard geckos, the researchers gently pinched the lizards to encourage them to shed their tails. As soon as a gecko felt threatened, its tail began to twitch and eventually detached from the rest of its body in an amazing, but nearly bloodless, feat.

The researchers immediately placed the severed tails into a recording arena, as shown in the video below.



Rather than using up all their energy in a single short burst, the gecko tails seemed to modulate their muscle movement to conserve energy and maximize the unpredictability of their behavior. The tails also changed direction and speed depending on what they bumped into, which suggests that the tails can independently sense and respond to their environment. The tail is buying the animal that shed it some time to get away.

Original article here.

Cell Phone Cricket Census in NYC

If you are in New York on September 11 and you have a cell phone and a good pair of ears, you can help with the first-ever comprehensive cricket census of New York City.

Biologists from the US Geological Survey are asking citizen scientists from the Big Apple to help them track the city’s cricket and katydid population. Participants in the NYC Cricket Crawl will go out between dusk and midnight to record cricket calls for one minute, and then immediately send their results and location to the scientists by cell phone.

The researchers are hoping to find evidence that the Common True Katydid, once plentiful in New York City but now rare, is still thriving in some regions of the city.

Scientists came up with the idea after reading a brief report on the mysterious disappearance of the common katydid on Staten Island, written in 1920. Although nearly 90 years have passed since the report, no one has solved the mystery of the missing katydid.

You don’t need any special equipment to become a Cricket Crawler, and there are two options for submitting your data: Either ID your own cricket songs and call or text in the results, or if you have access to a phone or digital camera with video, you can record what you hear and send the file directly to the scientists. Real-time cricket census data and interactive maps will be available as the night continues.

Original article here.