Sad:

The Panamanian golden frog communicates with other frogs by semaphore in the form of gentle hand waves.

http://news.bbc.co.uk/2/hi/science/nature/7219803.stm

What’s is amazing is that they took video of them in the wild before the last wild populations were destroyed by a fungi:

… after filming for the BBC One series Life In Cold Blood, the frogs had to be rescued from the wild, due to the threat of chytrid fungus.

More details on chytrid fungus and a possible cure:

http://news.bbc.co.uk/2/hi/science/nature/7067613.stm

The blow that chytrid has dealt to the frog population is already immense.

The disease has probably accounted for one-third of all the losses in amphibian species to date, says Professor Rick Speare, an expert in amphibian diseases who works with the University of Otago’s frog research group.

Update:
Just found this video on YouTube that from the BBC documentary mentioned above: