of biological diversity a short in food chain with tiny crustaceans at the top it's also a merrill mcpeak lake meaning that while most lakes frequently undergo physical mixing of water layers should stay more or less suspended in place leaving oxygen depleted depp's like we witnessed below the surface of ship. to study the make up of the each of the lakes fine layers the crescent team developed their own patented hydraulic sampler with the ability to collect specimens at intervals of just five centimeters. this strange contraption helped us to discover the thick purple. unit is unique in terms of the predominance and sheer numbers of purple sulfur bacteria. such a massive population of these types of bacteria. can be attributed to specific conditions to help the species thrive. physics institutes base camp after a day on the lake we went inside the on site laboratory to make sense of what we pulled out from under water. we find in the multicolored layers sucked out of should net for more than just the stablish. down there. from the lake are almost like rings on a tree a detailed record of this