In article .com,
wrote:

These articles quote resilience of 97% compared to 80% for synthetic
rubber:

http://en.wikipedia.org/wiki/Resilin

http://www.future.org.au/news_2005/august/insect.html

Other articles mention resilin being used in insect exo-skeletal shells
or beetle wings, possibly allowing such structures to store energy:

http://www.ncbi.nlm.nih.gov/entrez/q...bMed&list_uids
=10983820&dopt=Abstract

http://www.livescience.com/technolog...ct_rubber.html

I couldn't find anything about the UV resistance properties, although
perhaps some additive or modifier could be used to give UV resistance.
Couldn't find anything on tensile strength, either. Does anyone else
know?

With such a high mechanical efficiency, I'd wonder if one couldn't
perhaps even make flapping wing joints out of it. But what do you all
say -- what might be the best way to make use of this material for
mechanical airborn propulsion purposes?

As I posted earlier, it sounds interesting, but I am not going to build
something that depends on it until I can evaluate its mechanical
properties and how they stand up to the effects of aging, UV, heat,
cold, the usual solvents, fuels and lubricants found in aviation.

Until we have that information, resilin will be a potential, but
unproven, material. I would suggest that it be tried on model airplanes,
etc., to get a feel for its real-world properties.