2008/10/20 added comment with pointer to additional details and references
"The exact imitation of biological structures by using equivalent processes to those used in nature is extremely difficult, since the mechanisms of formation of biological structures are tremendously complex,"" Dr. Akhlesh Lakhtakia explained to Nanowerk. "An alternative approach to fabricate replicas of biological shapes is based on 'converting' templates harvested from a particular species to inorganic materials. This approach could result in a highly reproducible and inexpensive process for the fabrication of complex nanostructures with unique functionalities. This way, structures can be made out of more stable, harder and high-temperature-tolerable inorganic materials."
The article goes on to describe research on creating structures using templates from the compound eyes of fruit flies through 'conformal-evaporated-film-by-rotation' (CEFR) and 'oblique angle deposition' (OAD), improving the fidelity of replication as well as overcoming the sensitivity of biological templates to chemicals and high temperature. These techniques allow researchers to study the functional properties of structures in nature and may also lead to practical aplications.
"Many structures have evolved in nature to display interesting and useful properties. The most appealing of these properties are optical, imparting either coloration and/or camouflage to the organism. Optical imaging structures such as compound eyes or polarization-sensitive eyes are also attractive. Some of these structures may have properties in the infrared regime, and therefore may not be easily appreciated by casual human observers. If we could replicate easily these and other attractive features – eg. superhydrophobicity of ciliated objects such as lotus leaves – we could exploit them for various technical or scientific purposes."