New Scientist

Image: Rockman of Zymurgy

Getting fossilised in tree sap seems an odd way for an aquatic insect to meet its maker. Biologists have been left scratching their heads over how it happened. “Most previous studies have focused on non-aquatic insects, assuming that most resin solidifies at the tree bark,” says Alexander Schmidt of the Museum of Natural History in Berlin, Germany.

Now a study in Florida’s swamp forests, led by Schmidt, shows that resin trickles into small pools of water at the base of trees, where it forms a highly effective insect trap.

Schmidt found that resin at the bottom of a pond is probably more of a hazard to insects than resin on tree bark. He says the water delays the process of solidification and “amberisation” that is normally driven by oxidation in air. The resin stays stickier for longer under water, so it is more likely to trap insects (Proceedings of the National Academy of SciencesDOI: 10.1073/pnas.0707949104). He rejects convoluted explanations of aquatic insects being swept out of the water and into pools of tree sap. Read more on newscientist.com…