[Alamo-Girl]

Thank you so much for your reply! Truly, I wish the others here would defer to your insight on the article.

The authors showed how a naturally occuring temperature regulator differed from that of a designed regulator. The showed that the system they examined regulated temperature, not that it was "intended" to do so. If anything, they showed that the system did not appear to be designed.

I didn't suspect they were addressing "intent". OTOH, the design of the biological system to regulate temperature has a purpose, i.e. to regulate temperature.

In the end, they establish two things in biological systems: design and purpose.

They should have left it there. Causation cannot be addressed without the mathematics and physics - and intent is in the domain of philosophy.

[Doctor Stochastic]

...the design of the biological system to regulate temperature has a purpose...

You are assuming the conclusion. There is nothing in the paper that shows purpose, only use. Things may be used for various purposes; leather's first use may be holding cows together, but that doesn't stop it from being ant food later.