Beyond their pretty remarkable ability to “think” and problem-solve, slime molds are just plain beautiful.
John Bonner, a professor emeritus at Princeton, has been studying them for seventy years. He’s been fascinated by the ability of this “bag of amoebae encased in a thin slime sheath” to operate like a simple brain, despite its biological simplicity. He’s used the gooey little guys to further the study of evolution and development for over half a century, and some of the images he’s collected are stunning.
Bernie Peyton uses some of the best animal origami I’ve ever seen to call attention to threatened species and remind us that nature’s treasures (the living ones, not the paper ones) are worth protecting. Check out his gallery … I bet you can’t pick out a favorite!
[credit: (top) Susan Ford Collins on Flickr/ (bottom) Zina Deretsky, National Science Foundation, in collaboration with S. Cranford, G. Bratzel and M.J. Buehler (all three from Massachusetts Institute of Technology, and Rihcard C. Yu and Andaluz Yu of Green Pacific Biologicals ]
View a video interview with Markus Buehler of MIT, an animationof a spider web under extremes stresses, and an animation of a spider web subjected to mechanical forces.
While researchers have long known of the incredible strength of spider silk, the robust nature of the tiny filaments cannot alone explain how webs survive multiple tears and winds that exceed hurricane strength.
Now, a study that combines experimental observations of spider webs with complex computer simulations shows that web durability depends not only on silk strength, but on how the overall web design compensates for damage and the response of individual strands to continuously varying stresses.
1. Tissue slurry — Ontario, Canada This man-made lake in Terrace Bay, Ontario, Canada, is more than 500 metres long. It’s an aeration pond, part of the waste-treatment system at a factory that produces pulp for Kimberly-Clark tissues. “The treated water is returned to its source — often a river,” says Fair. Each yellow cone is an “agitator” that aerates and churns the liquid, assisting its breakdown. According to Worldwatch Institute figures, if recycled paper was used instead, 64 per cent less energy would be needed.and churns the liquid, assisting its breakdown. According to Worldwatch Institute figures, if recycled paper was used instead, 64 per cent less energy would be needed.
2. Fertiliser — Louisiana, US This emerald-tinted lake near Geismar, Louisiana, includes gypsum, uranium and radium. These chemicals result from manufacturing phosphorous fertiliser and are dumped into this impoundment to solidify. The world’s supplies of phosphates are dwindling and most are located in the US, China and Morocco. Unlike oil, however, there is no known renewable alternative for making fertiliser. “You think the resource crisis is in oil?” says Fair. “Think again.”
3. Spilled oil — Gulf of Mexico, US Fair captured this shot over the BP Deepwater Horizon spill at the Macondo well in June 2010, when 750m litres of oil leaked into the Gulf. “The stuff that was coming out of that well was all different colours,” says Fair. “We think of crude oil as being black — it’s all kinds of different colours and consistencies.” The bright red is the crude on the surface, reflecting light. The less viscous oil below the surface is purple-brown.
4. Liquid sulphur — Alberta, Canada At Fort McMurray in Alberta, Canada, a blood-red vein of liquid sulphur is pumped on to a bed of solidified yellow sulphur. The element is one of the major by-products of tar-sand upgrading and there is now an abundance of stocks globally. With prices low, producer Syncrude isn’t selling — it’s storing it in giant pyramids. Liquid sulphur, at around 200°C (its melting point is 115°C), is pumped into fenced-off compounds and left to harden.
5. Aluminium sludge — Louisiana, US This slurry pit is where the solid and liquid by-products of aluminium manufacture are separated. The process involves refining bauxite ore, which produces alumina. The waste includes bauxite impurities, heavy metals and sodium hydroxide (one of the chemicals used during processing). Fair estimates that the red-brown sludge has a pH of about 13, “meaning if you touch it, it burns the skin off”.
6. Fertiliser slurry — Louisiana, US This wintry-looking scene is a mix of lead, ammonia, mercury and ethanol — by-products of phosphate fertiliser production. “It’s a giant lake of waste,” says Fair, who shot the image 80km west of New Orleans in 2005. Owned by Mosaic Fertilizers, the plant, called Uncle Sam, has violated the US Clean Water Act nine times. The slurry pit is less than 3km from the banks of the Mississippi.
The Derweze area is rich in natural gas. While drilling in 1971, Soviet geologists tapped into a cavern filled with natural gas. The ground beneath the drilling rig collapsed, leaving a large hole with a diameter of 70 metres (230 ft). To avoid poisonous gas discharge, it was decided to burn it off. Geologists had hoped the fire would use all the fuel in a matter of days, but the gas is still burning today. Locals have dubbed the cavern “The Door to Hell”.
Single-celled organism can evolve multicellularity within months.
The origin of multicellular life, one of the most important developments in Earth’s history, could have occurred with surprising speed, US researchers have shown. In the lab, a single-celled yeast (Saccharomyces cerevisiae) took less than 60 days to evolve into many-celled clusters that behaved as individuals. The clusters even developed a primitive division of labour, with some cells dying so that others could grow and reproduce.
By using gravity as the selective pressure. In a tube of liquid, clusters of yeast cells settle at the bottom more quickly than single cells. By culturing only the cells that sank, Ratcliff selected for those that stick together. After many rounds of selection over 60 days, the yeast had evolved into ‘snowflakes’ comprising dozens of cells.
All spiders have unique mechanoreceptory organs called slit sensilla, which allow them to sense minute mechanical strains on their exoskeleton. This sixth sense makes it easy for spiders to judge things like the size, weight, and possibly even the type of creature that gets caught in their webs. It may also help them tell the difference between the movement of an insect and the movement of the wind, or even a benign blade of grass, as it moves across the web. 11 animals with a sixth sense
Two rotating spheres separated by thousands of kilograms of liquid sodium aim to mimic Earth’s interior.
Ten years in the making, the US$2-million project is nearly ready for its inaugural run. Early next year, the sphere will begin whirling around while loaded with 13,000 kilograms of molten sodium heated to around 105 °C. Researchers hope that the churning, electrically conducting fluid will generate a self-sustaining electromagnetic field that can be poked, prodded and coaxed for clues about Earth’s dynamo, which is generated by the movement of liquid iron in the outer core. If it works, it will be the first time that an experiment that mirrors the configuration of Earth’s interior has managed to recreate such a phenomenon.
The University of Maryland set-up consists of two concentric spheres. The inner sphere, at 1 metre across, stands in for Earth’s solid inner core; the outer sphere the edge of Earth’s mantle. The space between the two is filled with liquid sodium, mimicking the liquid outer core. Each sphere is powered by a separate motor so that it can rotate independently of the other. By spinning the spheres across a range of matched and unmatched velocities — up to 4 revolutions per second for the outer sphere and 12 for the inner — Lathrop and his team will study how heat and rotation might affect the movement of the molten iron in Earth’s core.
Lathrop and others hope that their work will shed light on how rotational forces in Earth’s core deflect flows of electrically conducting liquid into a configuration that produces a magnetic field with north and south poles. It might also help to explain what triggers changes in Earth’s magnetic field such as north–south pole reversals, which occur on average every few hundred thousand years, but can happen after a few tens of thousands of years or a few million. The last reversal was some 780,000 years ago. Over the past century and a half, the magnetic field has weakened by about 10%, leading some researchers to suggest that another pole-reversal is in the offing.
Asteroid Impact Craters on Earth as Seen From Space
Asteroid impact craters are among the most interesting geological structures on any planet. Many other planets and moons in our solar system, including our own moon, are pock-marked with loads of craters. But because Earth has a protective atmosphere and is geologically active — with plate tectonics and volcanic eruptions, mostly relatively young oceanic crust, and harsh weathering from wind and water — impact structures don’t last long and can be tough to come by.
But on a few old pieces of continent, especially in arid deserts, the marks of asteroids have been preserved. One well-known example is our own Barringer crater, also known as Meteor Crater, in Arizona. The images here show some of the biggest, oldest and most interesting impact craters on the planet.
A fire whirl, also known as a fire tornado or fire devil, is a rare phenomenon in which fire forms a tornado-like vortex of flames. Fire whirls can be formed in one of two ways: when a tornado spins too closely to a forest fire or when a heavy concentration of heat is generated in a small area. Typically, they’re spawned from wildfires. Like tornadoes, fire whirls vary in size and duration; however, they typically last no more than a few minutes.
Although it’s rare, this type of weather is extremely dangerous. In 1923, a fire whirl emerged during Japan’s Great Kanto Earthquake and killed 38,000 people. See some other amazing examples of the world’s weirdest weather.
I’m going to be making miniature versions of these in the studio for some Christmas shows in work! Flaming Christmas-pudding tornadoes!
Hey, remember the squid beak? Once you get past the beak, things get worse. Squid and octopuses are molluscs, like snails and slugs. Most molluscs have a thin ribbon inside their mouths called a radula, which they use to grind, rasp and cut up their food.
The image above is the radula of an octopus. It’s like a tongue, if a tongue was designed by a bad fantasy artist.