It's tempting to call them lords of the flies. For the first time, researchers have controlled the movements of free-flying insects from afar, as if t

Green beetles

The Berkeley team implanted electrodes into the brain and muscles of two species: green June beetles called Cotinus texana from the southern US, and the much larger African species Mecynorrhina torquata. Both responded to stimulation in much the same way, but the weight of the electronics and their battery meant that only Mecynorrhina – which can grow to the size of a human palm – was strong enough to fly freely under radio control.

A particular series of electrical pulses to the brain causes the beetle to take off. No further stimulation is needed to maintain the flight. Though the average length of flights during trials was just 45 seconds, one lasted for more than 30 minutes. A single pulse causes a beetle to land again.

The insects' flight can also be directed. Pulses sent to the brain trigger a descent, on average by 60 centimetres. The beetles can be steered by stimulating the wing muscle on the opposite side from the direction they are required to turn, though this works only three-quarters of the time. After each manoeuvre, the beetles quickly right themselves and continue flying parallel to the ground.

Brain insights

Tyson Hedrick, a biomechanist at the University of North Carolina, Chapel Hill, who was not involved in the research, says he is surprised at the level of control achieved, because the controlling impulses were delivered to comparatively large regions of the insect brain.

Precisely stimulating individual neurons or circuits may harness the beetles more precisely, he told New Scientist, but don't expect aerial acrobatics. "It's not entirely clear how much control a beetle has over its own flight," Hedrick says. "If you've ever seen a beetle flying in the wild, they're not the most graceful insects."

The research may be more successful in revealing just how the brain, nerves and muscles of insects coordinate flight and other behaviours than at bringing six-legged cyborg spies into service, Hedrick adds. "It may end up helping biologists more than it will help DARPA."

Brain-recording backpacks

It's a view echoed by Reid Harrison, an electrical engineer at the University of Utah, Salt Lake City, who has designed brain-recording backpacks for insects. "I'm sceptical about their ability to do surveillance for the following reason: no one has solved the power issue."

Batteries, solar cells and piezoelectrics that harvest energy from movement cannot provide enough power to run electrodes and radio transmitters for very long, Harrison says. "Maybe we'll have some advances in those technologies in the near future, but based on what you can get off the shelf now it's not even close."

Journal reference: Frontiers in Integrative Neuroscience, DOI: 10.3389/neuro.07.024.2009

Original article by Ewen Callaway for New Scientist

A Startup That Builds Biological Parts

Ginkgo BioWorks aims to push synthetic biology to the factory level.

In a warehouse building in Boston, wedged between a cruise-ship drydock and Au Bon Pain's corporate headquarters, sits Ginkgo BioWorks, a new synthetic-biology startup that aims to make biological engineering easier than baking bread. Founded by five MIT scientists, the company offers to assemble biological parts--such as strings of specific genes--for industry and academic scientists.

Biological parts: Ginkgo BioWorks, a synthetic-biology startup, is automating the process of building biological machines. Shown here is a liquid-handling robot that can prepare hundreds of reactions. Credit: Ginkgo BioWorks

"Think of it as rapid prototyping in biology--we make the part, test it, and then expand on it," says Reshma Shetty, one of the company's cofounders. "You can spend more time thinking about the design, rather than doing the grunt work of making DNA." A very simple project, such as assembling two pieces of DNA, might cost $100, with prices increasing from there.

Synthetic biology is the quest to systematically design and build novel organisms that perform useful functions, such as producing chemicals, using genetic-engineering tools. The field is often considered the next step beyond metabolic engineering because it aims to completely overhaul existing systems to create new functionality rather than improve an existing process with a number of genetic tweaks.

Scientists have so far created microbes that can produce drugs and biofuels, and interest among industrial chemical makers is growing. While companies already exist to synthesize pieces of DNA, Ginkgo assembles synthesized pieces of DNA to create functional genetic pathways. (Assembling specific genes into long pieces of DNA is much cheaper than synthesizing that long piece from scratch.)

Ginkgo will build on technology developed by Tom Knight, a research scientist at MIT and one of the company's cofounders, who started out his scientific career as an engineer. "I'm interested in transitioning biology from being sort of a craft, where every time you do something it's done slightly differently, often in ad hoc ways, to an engineering discipline with standardized methods of arranging information and standardized sets of parts that you can assemble to do things," says Knight.

Scientists generally create biological parts by stitching together genes with specific functions, using specialized enzymes to cut and sew the DNA. The finished part is then inserted into bacteria, where it can perform its designated task. Currently, this process is mostly done by a lab technician or graduate student; consequently, the process is slow, and the resulting construct isn't optimized for use in other projects. Knight developed a standardized way of putting together pieces of DNA, called the BioBricks standard, in which each piece of DNA is tagged on both sides with DNA connectors that allow pieces to be easily interchanged.

"If your part obeys those rules, we can use identical reactions every time to assemble those fragments into larger constructs," says Knight. "That allows us to standardize and automate the process of assembly. If we want to put 100 different versions of a system together, we can do that straightforwardly, whereas it would be a tedious job to do with manual techniques." The most complicated part that Ginkgo has built to date is a piece of DNA with 15 genes and a total of 30,000 DNA letters. The part was made for a private partner, and its function has not been divulged.

Assembling parts is only part of the challenge in building biological machines. Different genes can have unanticipated effects on each other, interfering with the ultimate function. "One of the things we'll be able to do is to assemble hundreds or thousands of versions of a specific pathway with slight variations," says Knight. Scientists can then determine which version works best.

So far, Knight says, the greatest interest has come from manufacturing companies making chemicals for cosmetics, perfumes, and flavorings. "Many of them are trying to replace a dirty chemical process with an environmentally friendly, biologically based process," he says.

Ginkgo is one of just a handful of synthetic-biology companies. Codon Devices, a well-funded startup that synthesized DNA, ceased operations earlier this year. "The challenge now is not to synthesize genes; there are a few companies that do that," says Shetty. "It's to build pathways that can make specific chemicals, such as fuels." And unlike Codon, Ginkgo is starting small. The company is funded by seed money and a $150,000 loan from Lifetech Boston, a program to attract biotech to Boston. Its lab space is populated with banks of PCR machines, which amplify DNA, and liquid-handling robots, mostly bought on eBay or from other biotech firms that have gone out of business. And the company already has a commercial product--a kit sold through New England Biolabs that allows scientists to put together parts on their own.

"If successful, they will be providing a very important service for synthetic biology," says Chris Voigt, a synthetic biologist at the University of California, San Francisco. "There isn't anybody else who would be characterizing and providing parts to the community. I think that this type of research needs to occur outside of the academic community--at either a company or a nonprofit institute."

Original article by Emily Singer for MIT Technology Review

Locust flight simulator helps robot insects evolve

Right:Smoke signals helps robots fly better (Image: Simon Walker, Animal Flight Group, Oxford University)

A LOCUST flight simulator could be the key to perfecting the ultimate surveillance machine: an artificial flying insect. The simulator can model the way wings of varying shapes and surface features beat, as well as how they change their shape during flight.

The device was created using extremely high-speed flash photography to track the way smoke particles flow over a locust's wings in a wind tunnel - a technique called particle flow velocimetry. This allowed researchers at the University of Oxford to build a computer model of the insect's wing motion. They then built software that mimicked not only this motion, but also how wing surface features, such as structural veins and corrugations, and the wings' deformation as they flap, change aerodynamic performance.

The work has shown that wings' surface structures are crucial to efficient lift generation, says lead researcher Adrian Thomas (Science, DOI: 10.1126/science.1175928).

The simulator could be a big step forward for the many teams around the world who are designing robotic insects, mainly for military purposes, though Thomas expects them to have a massive role as toys, too. "Imagine sitting in your living room doing aerial combat with radio-controlled dragonflies. Everybody would love that," he says.

Imagine sitting in your living room doing aerial combat with remote-controlled dragonflies

Until now, modelling insect wings involved building physical replicas from rigid materials and estimating how they might move from observations of insect flight. Thomas hopes the simulator will take the guesswork out of the process, especially as every flying insect has uniquely shaped wings and wing beat patterns.

Building miniature aircraft is of great interest to the armed forces. In the UK, for example, the Ministry of Defence wants to create a device that can fly in front of a convoy and detect explosives on the road ahead. In the US, the Pentagon's research arm DARPA is funding development of a "nano air vehicle" (NAV) for surveillance that it states must weigh no more than 10 grams and have only a 7.5-centimetre wingspan.

Last month, DARPA contractor AeroVironment of Monrovia, California, demonstrated the first two-winged robot capable of hovering flight (see video at http://bit.ly/18LR8U). It achieved a stable take-off and hovered for 20 seconds. Other DARPA-funded projects by Micropropulsion and Daedalus Flight Systems are also thought to have achieved hovering robotic flight this year.

"Getting stable hover at the 10-gram size scale with beating wings is an engineering breakthrough, requiring much new understanding and invention," says Ronald Fearing, a micromechanics and flight researcher at the University of California, Berkeley. "The next step will be to get the flight efficiency up so hover can work for several minutes."

But how can such machines be made more efficient? Better batteries and lighter materials will help, but most important will be improving wing structure so the aircraft more accurately imitate - or even improve upon - the way insects fly.

So how do insects fly? For a long time no one really knew. In 1919, German aeronautical engineer Wilhelm Hoff calculated that a pollen-laden bumblebee should not have enough lift to get airborne according to the rules of aerodynamics as understood at the time.

It wasn't until 1981 that Tony Maxworthy of the University of Southern California hit on a possible reason: his working model of a fly's wings, immersed in oil, showed large vortices were spinning off the leading edge of the wing as it beat (Annual Review of Fluid Mechanics, vol 13, p 329). Within the vortices air is moving at high velocity, and is therefore at low pressure, hinting at a lift-creating mechanism unlike that of conventional aircraft, in which an angled wing travelling forward deflects air downwards, creating an opposing upward force.

In 1996 Thomas was a member of Charles Ellington's team at the University of Cambridge, which identified the mechanism by which bugs created high lift forces - using a model of a hawkmoth. "We found a leading-edge vortex that was stable over the whole of the downstroke," says Thomas.

The nature of the leading-edge vortex is dependent on the size of the wings, their number, the pattern described by the beating wing and the wing structure.

This work has laid the foundations for researchers such as Robert Wood and his team at Harvard University, who are investigating ways to make insect wings (Bioinspiration and Biomimetics, DOI: 10.1088/1748-3182/4/3/036002). They have developed a new way to build flexible wings from moulds using microchip manufacturing techniques. Using elastic polymers and elegant, vein-like supporting structures, the researchers can build wings with variable camber, and with different corrugations embossed in them, in an attempt to mimic the in-flight aerodynamics and deformation of real insect wings.

Thomas is also focusing on the way insect wings deform in flight. "If we use a wing model with all the complex curves, twists and corrugations of the real insect it is 50 per cent more efficient than a model with rigid flat-plate wings, for the same lift generation. That would be a huge saving in power for a micro air vehicle," he says.

Although the Oxford team's simulator is geared for locust wings at present, the researchers are adjusting the software to model the hoverfly - with other insect types to follow.

"What we've shown is that modern aerodynamics really can accurately model insect flight," Thomas says. "That old myth about aerodynamics not being able to model bumblebee flight really is dead now."

oRIGINAL ARTICLE WRITTEN BY pAUL mARKS FOR nEW sCIENTIST