The Pentagon wants planes to start acting more like plants. That's the ultimate goal of a research project, funded by Darpa, the Defense Department's mad science division.

We all know plants change their shape. Some bend to catch the sun's rays; some snap to catch a meaty treat; some stiffen when they're watered. Darpa would like to have tough, man-made materials that can pull off some of the same tricks. Maybe, one day, it can lead to a jet that can pull back its wings when it's ready to attack, or extend 'em to glide.

Researchers at Virginia Tech have won from Darpa a $2.1 million, year-and-half grant to start to figure out ways to do this. "The plan calls for the investigation of the protein structures of plants for the purpose of understanding their role in generating shape changes in natural materials," says a Virginia Tech press release. "The protein structures under analysis would then be used to develop a synthetic material that incorporates properties that produce controllable shapes."

The project – Nastic Materials -- is part of a whole range of efforts by Darpa to make materials that act a little like living things. As John Main, the program's manager, said at a DarpaTech conference earlier this year:

The intersection of materials science and nature appears to show great promise for delivering materials with unobtainable properties.

Natural materials are truly magnificent: Living bones grow, repair damage, remodel to distribute stress, and produce blood. Muscle turns lipids into work to help us regulate body temperature, maintain balance, and walk. Plant tissues grow, distribute nutrients, isolate injury, self-clean, support leaves, and sometimes even move with surprising force, such as tree roots upending concrete sidewalks.

All of these characteristics are unobtainable [in man-made things] if you limit yourself to the world of conventional materials. Yet they are all clearly possible, because nature has supplied us with examples to study and potential paths to follow to create similar capabilities.