Two Steps Forward…

Today’s technology is often said to be developing at an exponential rate, and it’s growth is almost as often described in terms of evolution, in stark contrast to Thomas Edison’s celebrated “inspiration and perspiration” formula for invention.

Some who take this view seem to equate evolution with the unstoppable march of progress – a correspondance biologists have long since abandoned. Nowhere is this more evident than among those who believe we are approaching a Singularity – a moment when technological development outstrips our ability to understand it, much less manage it.

But this doesn’t stand up to closer examination. What we percieve in the short term as explosive progress may dissolve into near stasis if we take a longer view. That’s not to deny that we are in an era of rapid progress, with all kinds of technologies obeying Moore’s Law. But we cannot assume that this will continue forever and history suggests it won’t.

Perhaps we should stop searching for grandiose metaphors to describe our progress and admit that Edison had it right after all – our progress is only fuelled by the great minds behind it.

Mouse in Snake’s Clothing

It’s not just snakes that shed their skins, African spiny mice employ this tactic too, to escape predators by tearing off chunks of skin as a distraction. They are the first mammals known to do , and the wounds heal rapidly.

Very Fruity!

The berry-like fruit of Pollia Condensata- a forest plant from sub-saharan Africa – has been discovered to be the most iridescent organism in the naural world, overtaking the Morpho butterfly. The intense blue colour is caused by the way light reflects off tiny structures on the surface of the seeds, enticing birds to eat and spread the seeds, which offer  little nutritional value to hungry animals.

 

 

Treadmill Cheetah Beats Bolt

Machines are now officially faster than humans. Boston Dynamics’ Cheetah robot has clocked a top speed of 45.5 kilometres per hour – outstripping the worlds fastest man, Usain Bolt. Like a real cheetah, the robot uses a hopping gait at low speeds before increasing its stride and pace by flexing its back with each step.

But Cheetah has to run on a treadmill and requires atether to supply power and keep it upright, something Bolt obviously does not need to do.

 

September 2012 – If Lizards Can’t Do It, How Can Humans?

The regenerated tail of a lizard is not a perfect replica of the original, but a poor knick-off with a different anatomy. This finding raises the question of whether it will ever be possible to fully regenerate injured human limbs – despite optimistic claims to the contrary.

Rebecca Fisher of the University of Arizona College of Medicine in Phoenix and her colleagues discovered key anatomical differences when they looked at original and fully regenerated tails in the green anole lizard (Anolis carolinensis), which can “drop” its tail when caught by a predator and later grow another. Running through the new tail, for example, was a single tube of cartilage rather than the hain link of vertebrae found in the original.

The muscles were different too. In place of shorter, variegated muscle fibres were long muscles stretching from tip to stump.

Both differences suggest the regenerated tail would be less flexible, says Fisher, because neither cartilage tube nor the long muscle fibres are capable of the fine control that comes with shorter muscles and lots of small joints between the bones. Further functional studies should show what changes these might make to the lizard’s agility.

Most intriguing to Fisher were the pores she noticed throughout the cartilage. A tail made of vertebrae has regular gaps that allow blood vessels and nerves to pass through. But the replacement cartilage, perhaps because  it is all one piece, is peppered with small holes, which increase in number towards the tip of the tail. The pores only let blood vessels through – not nerves. New nerves either remain trapped within the cartilage tube or spread a short distance from the stump and don’t seem to reach the muscles or the skin except right at the base of tail.

Whether the findings will put a dampener on hopes of eventually regenerating human limbs remains to be seen. Jason Pomerantz, a regenerative medicine researcher at the University of California, San Francisco, says there are big implications in the differences between the regenerated structure an original. “Even in a context that we think of as a ‘good’ example of regeneration, the regenerated structure is not perfect and functioning as well as the original”, he says. It highlights the challenge of regenerating a complicated structure, he adds.

Ellen Heber-Katz, a mammalian tissue regeneration specialist at the Wistar Institute in Philadelphia, Pennsylvania, is more optimistic. A range of animals can regenerate limbs or tails, and one lizard species may not refllect the capabilities of mammals, she says.

 

September 2012 – Idle Muscles Keep Your Body Warm

Muscles keep the body warm – and not just by making us shiver.
The body’s main thermostat was thought to be brown fat, which burns white fat in cold conditions. But when Muthu Periasamy of Ohio State University in Columbus surgically removed brown fat from mice, the rodents could still maintain body temperature in the cold.
The secret is the muscle, he says. Mice that were genetically engineered to lack a muscle protein called sarcolipin were unable to survive cold conditions after their brown fat was removed.
Periasamy also found that mice lacking sarcolipin piled on weight, which suggests the protein may help combat obesity.