Cavers' shadows in underground lake (IMAGE)
Caption
The silhouettes of divers Nadir Quarta and Kenny Broad can be seen in Lago dell'Orsa as they descend in search of biofilms to sample.
Credit
Dani Buchheister/Penn State
Usage Restrictions
Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted.
License
CC BY-NC-ND