New Primate Fossil Poses Further Challenge to Ida

Pour more rain on Ida's parade. Last May, a team of researchers announced that the 47-million-year-old lemurlike fossil represented a missing link between primitive primates and humans. Many paleoanthropologists were skeptical, however, and shortly thereafter a new find challenged Ida's status. Now, another skeleton has come out of Ida's closet: a younger relative from Egypt that shows Ida's resemblance to apes and humans is only superficial.Researchers have named the new primateAfradapis longicristatus, a name that pegs it as an African member of an extinct group of primitive primates known as Adapiformes, to which Ida also belongs. Some researchers have long argued that Adapiformes might be primitive relatives of anthropoids--the higher primates including monkeys, apes, and humans--rather than ancestors of lorises and lemurs. But new fossils found over the past 20 years in Asia and Africa proved to be better candidates for the earliest anthropoids. Thediscovery of anthropoid-like features in the remarkably complete skeleton of Ida (Darwinius masillae), however, led the researchers who analyzed her remains to resurrect the view that Ida and, hence, adapids, were direct ancestors of anthropoids.If Ida were truly a missing link between early primates and us, then Afradapis, which appeared 10 million years after Ida, should also share the same traits with the earliest undisputed anthropoids that were alive at about the same time and in the same place. But that's not what Erik Seiffert of Stony Brook University in New York state and Elwyn Simons of Duke University in Durham, North Carolina, and their colleagues found when they unearthed Afradapis in the Fayum desert of Egypt in 2001. Working with 100 teeth and jaws from multiple individuals--all about 37 million years old--they compared 360 morphological traits in 117 living and extinct primates, in the most complete analysis assembled so far of extinct primates. When they scored Ida and Afradapis against those other primates, Seiffert and colleagues found that adapids do share some traits with anthropoids, such as the loss of a third upper and lower premolar. But these traits evolved more than once among primates, the team reports tomorrow in Nature. They are the result of convergent evolution, which is the acquisition of the same biological trait in unrelated lineages--and, thus, do not indicate inheritance of the trait from a shared ancestor.Indeed, other extinct primates, including two species from the Fayum in Egypt that are about the same age asAfradapis, had not evolved those so-called anthropoid-like traits (such as the loss of the premolar). And another new discovery of a 37-million-year-old primate from Asia called Ganlea megacanina also had features that suggest it is an early anthropoid--but not the same ones that supposedly tie Ida or Afradapis to our lineage. All these lines of evidence suggest that those "anthropoid-like" features emerged later and independently in anthropoids, says Seiffert. "It's coincidental."One of the researchers who studied Ida, however, responds that Ida andAfradapis look more like the group that gave rise to anthropoids than the group that gave rise to lemurs and lorises--and that there are too many traits to dismiss as convergent evolution. "The complete convergence postulated for Afradapis seems implausible to me," says paleontologist Philip Gingerich of the University of Michigan, Ann Arbor.Other researchers, however, say that the new analysis convincingly shows that adapids, including Ida, were not our direct ancestor. "Adapids never were a good bet for [higher primate] relatives, and the more data we get, the worse the case gets," says paleontologist Callum Ross of the University of Chicago in Illinois, who was not involved in either the Ida or Afradapis papers. Adds paleontologist K. Chris Beard of the Carnegie Museum of Natural History in Pittsburgh: "This debate over adapids would have been dead long ago if it weren't for Ida."

By Ann Gibbons

Gizmo Converts Light Into Motion

Enlarge Image

Conceptual bridge. This tiny silicon beam links light to vibration, potentially opening the way to technologies that combine optics and mechanics.

CREDIT: M. EICHENFIELD ET AL.,NATURE, ADVANCED ONLINE A tiny ladderlike beam of silicon converts light into vibrations and vice versa with extremely high efficiency, physicists report. That may seem like an esoteric result, but the finding could open the way to new physics and someday serve as a key element in optical microcircuits akin to the electronic microcircuits in computer chips.

Although the effect is ordinarily very small, light exerts forces on the things it strikes or flows through. In recent years, physicists have exploited those forces to set micrometer-sized objects aquiver. For example, 4 years ago, a team led by Kerry Vahala of the California Institute of Technology (Caltech) in Pasadena showed that light leaking out the side of a nearby optical fiber could make a tiny disk of glass vibrate. And 2 years ago, Daniel Gauthier of Duke University in Durham, North Carolina, and colleagues showed that light traveling down a fiber could make the fiber itself shake. In fact, they stored a pulse of light as a vibration and released it nanoseconds later.

Now, Oskar Painter, Matt Eichenfield, and colleagues at Caltech have taken these efforts a big step forward. Along with Vahala, the applied physicists have designed a gadget that increases the strength of the interaction of light and vibrations by orders of magnitude, potentially opening the way to optical microchips in which low-frequency vibrations or microwaves control high-frequency optical signals or vice versa. The device combines two different but related fields: photonics and phononics.

For more than a decade, physicists have been developing so-called photonic crystals. These are samples of glass or other light-transmitting materials filled with regular patterns of holes, which alter the way light waves can travel--in much the same way that the array of atoms in a crystal affects the way electrons can move through it. In such photonic crystals, light of certain wavelengths cannot propagate, as the waves overlap and interfere to cancel themselves out. However, light of such a wavelength can be trapped within the crystal if the spacing of the holes is changed in one spot to allow it to exist there. Sound also consists of waves, so similar holey structures can be used to make phononic crystals that affect sounds in much the same way.

Eichenfield, Painter, and colleagues fashioned a hybrid photonic/phononic crystal out of a tiny bridge of silicon less than a micrometer wide and about 20 micrometers long. They etched rectangular holes into the beam to make a ladderlike structure, with several of the holes in the middle slightly closer together to trap light and vibrations of the same wavelengths but vastly different frequencies. The researchers then fed light into the beam with an optical fiber and measured the light reemerging from it. At predictable wavelengths, the amount of light coming back out dipped, showing that some of the light was getting trapped in the beam.

The researchers also looked at the total range of frequencies of the light coming out and found that some of it had been transferred to microwave frequencies--the exact frequencies of trapped vibrations, the team reports online this week in Nature. That shift proved that the light was making the beam vibrate and that the jiggling was then affecting the light and converting some of it to microwaves. In fact, each photon pushes on the beam with 10 times the force of gravity, Painter estimates.

"It's an incredibly exciting piece of work," says Duke's Gauthier. That's because the conversion of light to vibration is so much stronger than it has been in previous experiments. "People tend to use meters of optical fiber and milliwatts of laser power, whereas they have used a micrometer-sized device and microwatts of power." The device could have numerous applications, says physicist John Page of the University of Manitoba in Winnipeg, Canada. Specifically, the advance could pave the way to using vibrations or microwaves to control optical signals and to fashion switches, filters, or mixers in optical circuits on microchips.

By Adrian Cho

Why hack a calculator? Why climb Mount Everest?

So you're a programmer deciding where to invest your energy. What's a better idea: the latest Apple device, where hot new games can mean big bucks and millions of users, or a calculator introduced 10 years ago?

ticalc.org news editor Michael Vincent

(Credit: Michael Vincent)

Most go for iPhones and iPods. But another community thrives in its own way. These are the folks who spend hours trying to elevate their Texas Instruments calculators to a level far surpassing their modest roots.

Among their achievements: adding new features, creating new operating systems, connecting the calculator to keyboards and other hardware, playing a video excerpt from "The Matrix," and even running Nintendo Game Boy video games. Not bad for calculators such as the $100 TI-83 Plus, introduced in 1999 with a Z80 processor running at 6MHz, 24KB of memory, 160KB of flash memory, and a 96x64 pixel display.

Why all this work for projects that realistically are not going to reshape the future of computing? Much of the motivation parallels mountaineer George Mallory's rationale for climbing Mount Everest: "Because it's there."

TI's graphing calculators are programmable, affordable, and widely used in schools--a lot more approachable than a Himalayan peak. That doesn't mean they're easy. The calculators must be programmed in assembly language--a slightly more human-readable version of the very basic machine code the calculators execute, but hardly something more easily read and debugged such as C or Java.

'Squeeze to get the juice'
Although TI calculator hackers may be an uncommon breed, plenty of people relish a good challenge.

Dan Englender, a 26-year-old in Washington, D.C., who was very active in TI hacking for years and wrote the MirageOS for the calculator family, enjoys the challenge. "They're kind of fun to play with as they come from the factory, but they're even more fun when you make them do stuff they weren't designed to do," he said. "It's remarkable what you can squeeze out of those calculators...but you have to really squeeze to get the juice."

Adds Michael Vincent, "The motivations for this sort of work are largely challenge with some utility mixed in. For me personally, my hacking efforts were all about achieving what has previously been impossible." Vincent in 2002 wrote the CEPTIC operating system for the TI-83 Plus and now is news editor for the ticalc.org site.

For Brandon Wilson, exploring every last nook and cranny of a TI calculator is part of the appeal.

"For me it's figuring out something new," said Wilson, a 25-year-old programmer at a call center in Elizabethton, Tenn. He's been using TI calculators since seventh grade, developed a way to install third-party operating systems on the calculator earlier this year, and now is writing his own. "There's a lot of satisfaction being able to understand something so completely. It's very rewarding, at least for me."

Dan Englender's collection of calculators and other electronics shows what it takes to be a serious calculator hacker.

(Credit: Dan Englender)

And as with mountaineering exploits, there's also some measure of recognition.

One high point for Englender came during dorm-dweller introductions in his freshman year of college. Upon hearing Englender's name, one fellow approached him. "'You're Dan Englender? You wrote MirageOS?' They had heard of me and knew of my software, which was unexpected and gratifying," he said.

That recognition is part of the social element of TI calculator hacking. As with open-source software development, some people enjoy being part of something bigger than themselves.

The community ties were on display earlier this year when one person, Benjamin Moody, revealed that he'd cracked the 512-bit digital key used to sign the operating system on the TI-83 Plus calculator after a three-month brute-force calculation effort on his PC.

"Once that was released, a community effort was set up to factor the remaining keys for all of the other calculators. Hundreds of people joined in the effort after I posted news about it on ticalc.org," Vincent said. "With hundreds of computers cracking, it took but about a month to crack all remaining keys for every model of calculator."

Making a difference
It's not all an academic exercise. Calculators often are permitted in schools that ban mobile phones and gaming devices, so calculator games can be popular. Among the options are Tetris, Mario Brothers, Sonic the Hedgehog,car racing, and some role-playing games.

TI calculator hacker Brandon Wilson

(Credit: Brandon Wilson)

Those programs can be a bane as well as a boon. "I was teacher for two years. I know I removed games from calculators in my classroom. It's a distraction for students," Englender said.

Hacked calculators also can open up new possibilities for their intended purpose, performing mathematical calculations.

"The difference between a low-end calculator and a high-end calculator is 99 percent software. While the TI-89 series is faster and has more memory than the TI-83 Plus, that in itself is not the reason why the TI-89 is more advanced," Vincent said. Adds Englender, TI has calculators for middle school, high school, and college, but the college student might not want to drop another $150 for a new model.

And there's something personal to gain, too. Wilson believes he's a better programmer as a result of his TI hacking.

TI's non-cooperation
Texas Instruments, which didn't respond to a request for comment for this story, doesn't embrace the hacking community or its results. Most recently, they sent letters demanding that people remove the operating system signing key from their Web sites. Wilson was among those to receive the letters, which said the programmers were violating the Digital Millennium Copyright Act. Having the signing key makes it easy to install an alternative operating system on a calculator; software efforts before that relied on complicated installation methods or running software atop TI's operating system.

Some complied with TI's demand, but while the company may have won a battle, it may yet lose the war. TheElectronic Frontier Foundation argues TI's DMCA letters are baseless, and some TI calculator hackers represented by the EFF plan to republish their posts later this month.

So how did it feel to receive the letter?

"I certainly felt bad," Wilson said, but he's not deterred. "I've been deeply involved in this community for a long time. It's important to me. I'm not going to stop just because of one DMCA notice," he said.

Perhaps perversely, TI's stance also is something of an incentive. "That's part of what makes it fun. There's no company that helps you. You're on your own," Wilson said. "TI and the community have a long history of not helping each other."

The TI-83 Plus calculator

(Credit: Texas Instruments)

Vincent expected some legal action from TI, but not at the scale they actually took that action.

"I was very surprised that they blanketed the Web with them, sending them to bloggers who merely linked to ticalc.org or to other Web sites describing the crack," Vincent said. "I felt that TI shot themselves in the foot by turning this into a huge event."

TI hasn't always been a roadblock, though.

Englender, who saw the DMCA letters as "corporate bullying," was also around when TI voluntarily released the digital key needed to sign calculator software.

"Originally when they released the TI-83 Plus, you had to pay, like with Apple, a developer fee and had to download the software developer kit. Before you could release the application you had to send to TI and they would approve or deny it," Englender said. "At some point they decided to give out the application signing key. That was a wonderful gesture to the development community."

Though the calculator community remains vibrant, Englender--who has stepped back from active TI calculator hacking himself--can see a time when newer challenges such as mobile phones or Web-based applications hold more appeal.

"Cell phones are becoming increasingly powerful and accessible to programming," Englender said. "People who would otherwise have been interested in hacking calc because it was accessible might want to hack their iPhoneor BlackBerry or Palm Pre."

Correction 6:10 p.m. PDT: This story incorrectly attributed a quotation about climbing Mt. Everest. George Mallory said the words, "Because it's there."

by Stephen Shankland

Myths and realities of nano futures

Ever since John Dalton convinced the world of the existence of atoms in 1803, scientists have wanted to do things with them.

Machines in the blood: Still science fiction

Nanotechnology takes that ability on to a new plane and opens up all kinds of futuristic imaginings.

Essentially, nanotech is manipulation at the molecular scale - distances that may cover just a few millionths of a millimetre.

But its potential is not just about being able to miniaturise things. Indeed, scientists and engineers recognise that there are fundamental limits to pure miniaturisation.

Working at a scale a million times smaller than a pinhead allows researchers to "tune" material properties, making them behave in different ways to normal, large-scale solids.

This behaviour can be exploited in quite ground-breaking ways.

Geckos do it

Nature has been doing nanotechnology for a long time, and it has become expert in it. Consider the super-fine hairs on a gecko's feet which allow it to stick to walls and even hang upside down on a glass sheet.

How nanotechnology is building the future from the bottom up In pictures

Learning from nature, nanotechnology promises humans ways of making systems that are smaller, lighter, stronger, more efficient, but cheaper to produce.

"Nanotechnology is not a technology in its own right," explained Professor Mark Welland, head of the University of Cambridge Nanoscale Science Laboratory.

"It is an enabling technology, so it will appear in many different products.

"It is already appearing in flash memory, computer chips, and it will increasingly be an enabling technology in other products like coatings, new types of sensors, especially in the medical area."

It is expected to transform the performance of materials, like polymers, electronics, paints, batteries, sensors, fuel cells, solar cells, coatings, computers and display systems.

In five years' time, batteries that only last three days will be laughable, said Professor Welland. Similarly, in 10 years' time, the way medical testing is done now will be considered crude.

To say that in five years, an iPod will have 10 times its current storage capacity will be conservative, he said.

In the not-so-distant future, a terabit of data - equivalent to 10 hours of fine quality uncompressed video - will be stored on an area the size of a postage stamp.

Clearly, the devices themselves will not be nano-sized. But nanotechnology will play its part in shrinking components, and making them work together a lot more efficiently.

Although nano-devices can be built atom by atom, it is not realistic as a manufacturing option because it is slow and expensive, thinks Professor John Ryan, head of the Bionanotechnology Centre at Oxford University.

"One of the major scientific challenges in the years ahead is to understand the fundamental biological principles and apply them to produce new types of nanotechnology," he said.

"Armed with these design rules it may then be possible to make new types of nano-device using materials that are more robust than bio-materials."

Future fears

Proponents say misconceptions and misrepresentation of nanotechnology's potential have fuelled many dystopian scenarios. Some are frightening, others are impossible.

The Royal Society and the Royal Academy of Engineering has looked at current and future developments in nanotechnology and has reported on whether it will require new controls.

It is hoped that the report grounds some unrealistic scenarios, while recognising that real concerns need to be addressed with regulation.

"The one fantastical idea that has dogged nanotechnology is the self-replicating machine, the 'grey goo', scenario," said Professor Welland.

"That is simply too far off. I think anyone who is worrying about self-replicating machines should not be looking at nanotechnology for that.

"The complexity of designing a molecular machine is bad enough, but if you try to imbue that with self-replication, you could not even put a toe in the water to design it."

SOME SHORT-TERM NANO USES Medical diagnostic tools and sensors Solar energy collection (photovoltaics) Direct hydrogen production Flexible display technologies and e-paper Composites containing nanotubes Glues, paints and lubricants New forms of computer memory Printable electronic circuits Various optical components Source: Inst of Nanotechnology

The scenario sees swarms of self-replicating robots, smaller than viruses, multiplying uncontrollably and devouring Earth.

Eric Drexler, who many consider to be a "father of nanotechnology", has distanced himself from the idea, saying such self-replicating nanomachines are unlikely to be widespread.

Similarly, fears over "green goo", the concern that self-replicating, nano-sized biological particles will move into human bodies and do unpredictable things, is scaremongering, thinks Professor Welland.

Professor Ryan agrees: "These science fiction scenarios have not only diverted attention away from the real advantages of nanotechnology, but also from issues that do raise concern."

Inhaled nanoparticles found in the bloodstream which have dispersed throughout the brain is a concern, he says. Whether this poses a health risk is not known.

"If you look around at the moment in a big city, a significant proportion of material that you breathe in is already particulates - and a proportion of that is nano-sized, like diesel emissions," said Professor Welland.

Range of impacts

Nano-materials exploit unusual electrical, optical and other properties because of the very precise way in which their atoms are arranged.

This means fabrics could change colour electronically. Exposing an army uniform to ultra-violet light could activate changes without undressing.

But it is in medicine that nanotechnology offers the most remarkable advances, according to Professor Ryan.

"Nanomedicine will provide earlier and better diagnostics and treatment will combine earlier and more precisely targeted drug delivery," he said. The possibility of individualised therapy is also on the horizon.

Nanotechnology in the form of flexible films containing miniaturised electrodes is expected to improve the performance of retinal, cochlear and neural implants.

And it could lead to the miniaturisation of medical diagnostic and sensing tools, said Professor Ryan, which could drive down costs of such kits for developing countries.

In this respect, nanotechnology could enable developing nations to leapfrog older technologies, in the way that copper wire and optical fibre telephony were superseded by mobile phones.

Material changes

Industrial giants like GE are heavily involved in developing nanotechnology.

"We think that the biggest breakthroughs in nanotechnology are going to be in the new materials that are developed," said Troy Kirkpatrick at GE Global Research.

These include corrosion-resistant coatings to make hydro-electric turbines more efficient in heavily-silted waters, and nano-membrane water filters to make for faster filtration.

SOME LONGER-TERM NANO USES Miniaturised data storage systems with capacities comparable to whole libraries' stocks PCs with the power of today's computer centres Chips that contain movies with more than 1,000 hours of playing time Replacements for human tissues and organs Cheap hydrogen storage possibilities for a regenerative energy economy Lightweight plastic windows with hard transparent protective layers Source: Inst of Nanotechnology

GE is also studying the properties of nano-ceramics, which can offer extreme strength, while still being lightweight.

Because of the molecular structure of such materials, nano-ceramic coatings on aircraft could make them 10% more efficient, so less energy is used, producing fewer emissions.

GE Global Research is also looking to the electronics industry.

"If you look at the chip makers of the world, the challenge they have is not to figure out how to make them faster.

"The problem is they run so fast, the chips generate too much heat and melt. They need better materials for heat management," said Mr Kirkpatrick.

Using materials which exploit properties of nanoparticles, GE has developed chip adhesives that can transfer heat out of the processor system more efficiently.

"It is a start, and it is to show nanotechnology is finding its way into production and is changing the way we are doing science," said Mr Kirkpatrick.

Uncertainties and worries

Whatever nanotechnology does for the future, it will be an evolutionary process.

One certainty is that there remains a plethora of uncertainties in the emerging field of nanotechnology.

"Medical sensing is very attractive to everybody, but there could be a downside," explained Professor Welland.

"If medical sensors become ubiquitous, our physical state could be monitored 24 hours a day, and if someone hacked into that data, there could be concerns."

Which is indeed why regulation has to be addressed, but must not stifle nanotechnology's potential.

"One of the important things for me is that it ultimately means the most efficient use of materials and processes, which means it does not have to benefit just the G8 nations," argued Professor Welland.

"These sorts of materials, if they are able to do their job using less energy, should be available to everybody."

SOME POTENTIAL USES OF NANOTECHNOLOGIES 1 - Organic Light Emitting Diodes (OLEDs) for displays 2 - Photovoltaic film that converts light into electricity 3 - Scratch-proof coated windows that clean themselves with UV 4 - Fabrics coated to resist stains and control temperature 5 - Intelligent clothing measures pulse and respiration 6 - Bucky-tubeframe is light but very strong 7 - Hipjoint made from biocompatible materials 8 - Nano-particle paint to prevent corrosion 9 - Thermo-chromic glass to regulate light 10 - Magnetic layers for compact data memory 11 - Carbon nanotube fuel cells to power electronics and vehicles 12 - Nano-engineered cochlear implant