It's a geek, geek, geek, geek world

Four relatively recent notes from the science front.

- May 29: The International Herald Tribune reported on an study published in the scientific journal Nature indicating that futuristic images of brain-machine interfaces may be closer than we thought.

Two monkeys with tiny sensors in their brains have learned to control a mechanical arm with just their thoughts, using it to reach for and grab food and even to adjust for the size and stickiness of morsels when necessary, scientists reported on Wednesday. ...

The findings suggest that brain-controlled prosthetics, while not practical, are at least technically within reach. ...

The new experiment goes a step further [than previous ones]. In it, the monkeys' brains seem to have adopted the mechanical appendage as their own, refining its movement as it interacted with real objects in real time. The monkeys had their own arms gently restrained while they learned to use the added one.

The monkeys even came to putting the robot fingers in their mouths to suck off the sticky residue from when they had picked up marshmallows.

There are still bugs before this could be a practical technology, not the least of which is that the implantable electrode grids used to control the arm tend to fail after just a few months and no one is sure why. Still, this is an impressive result. As University of Montreal neuroscientist Dr. John Kalaska said in an accompanying editorial in Nature, systems such as these, when perfected,

would allow patients with severe motor deficits to interact and communicate with the world not only by the moment-to-moment control of the motion of robotic devices, but also in a more natural and intuitive manner that reflects their overall goals, needs and preferences.

I admit I find the idea of a brain-machine interface the tiniest bit creepy - but not nearly creepy enough to refrain from celebrating the sort of potential Dr. Kalaska outlined.

- June 29: I can't understand why, but for 15 years no one blew through either of two skull-shaped clay whistles found in the hands of a skeleton buried in an Aztec temple.

When someone finally did, the shrill, windy screech made the spine tingle.

If death had a sound, this was it.

Roberto Velazquez believes the Aztecs played this mournful wail from the so-called Whistles of Death before they were sacrificed to the gods.

The 66-year-old mechanical engineer has devoted his career to recreating the sounds of his pre-Columbian ancestors, producing hundreds of replicas of whistles, flutes and wind instruments unearthed in Mexico's ruins.

For years, many archaeologists who uncovered ancient noisemakers dismissed them as toys. Museums relegated them to warehouses. But while most studies and exhibits of ancient cultures focus on how they looked, Velazquez said the noisemakers provide a rare glimpse into how they sounded. ...

Velazquez is part of a growing field of study that includes archaeologists, musicians and historians.

Velazquez says that for too long, archaeology treated ancient civilizations as if they were deaf and dumb.

That's changing, said Tomas Barrientos, director of the archaeology department at Del Valle University of Guatemala.

"Ten years ago, nothing was known about this," he said. "But with the opening up of museum collections and people's private collections, it's an area of research that is growing in importance."

Archaeologist Paul Healy notes that we may never know just how these ancient instruments were intended to sound because "we don't have sheet music" for them. Still, even just the types of different sounds can give a deeper understanding of cultures that for too long stood silent.

- July 4: The Beeb describes how a new study published in the journal Science offers confirmation of what astronomers have suspected for some time: Mercury, the smallest planet in the solar system, is shrinking.

Data from a flyby of Mercury in January 2008 show the planet has contracted by more than one mile (1.5km) in diameter over its history.

Scientists believe the shrinkage is due to the planet's core slowly cooling.

That same cooling, it's believed, powers Mercury's magnetic field.

The Messenger (Mercury Surface, Space Environment, Geochemistry and Ranging) spacecraft passed within 200km (125 miles) of Mercury earlier this year.

It was the first time the planet had been viewed up close since Mariner 10's third and final fly-by in March 1975.

The flyby was one of three to be made by the craft as it prepares to enter into orbit around the Solar System's smallest planet in 2011.

During that earlier flyby

[c]ameras revealed a densely cratered world - with wrinkles. Planetary geologists call them "lobate scarps" and, like wrinkles on a raisin, they are thought to be a sign of shrinking.

A belief that appears to be confirmed.

- July 6: According to a release in ScienceDaily, findings by Great Ape Trust of Iowa scientist Dr. Serge Wich show that populations of the endangered wild orangutan are declining more sharply than previously thought.

Orangutans live in the wild only on the islands of Sumatra and Borneo and estimates of their numbers have dropped so sharply over just the past four years - down 14% on Sumatra and 10% on Borneo - that if urgent action is not undertaken, they could in just a few more years become the first great ape species to go extinct.

Dr. Wich blamed the decline mostly on illegal logging and the expansion of palm oil plantations which have served to both reduce and splinter the orangutan's habitat.

The report, originally published in the conservation journal Oryx, also included a number of recommended actions to halt the decline, perhaps most important of which is creating the government will to enforce good land use policies.