August 28, 2012
Scientists Document Oldest Occurrence Of Arthropods Preserved In Amber
April Flowers for redOrbit.com - Your Universe Online
Three tiny ancient insects have been found trapped in amber. These well-preserved specimens are encased in what is likely Earth's oldest bug trap.They were found in Italy, and though it sounds like something out of the plot of Michael Crichton's Jurassic Park, it isn't. These bugs are much older than that. They are about 230 million years old, which puts them in the Triassic period, and about 100 million years older than what had previously been the oldest known creatures trapped in fossilized tree resin, or amber.
Tree resin is a gooey substance much like sap, but without water, and it cannot be diluted.
Scientists examined 70,000 droplets of amber found in northeastern Italy. What they found were two microscopic mites and most of a fly. The mites are too small to be seen with the naked eye, and the fly is just a bit smaller than a modern fruit fly, says the study published in the Proceedings of the National Academy of Sciences.
Older insects fossils have been found in rocks, however these are different because they are not compressed and are much better preserved.
Grimaldi compared the mites to modern day examples and was surprised at how similar they are. Except for some difference in the mouth and fewer legs, "they're dead ringers for (modern) gall mites," he said. The modern ones can be found in bubbles or galls on plant leaves.
The similarities are surprising because the world has changed so drastically since the Triassic period. There were some early dinosaurs, no flowering plants and one huge continent called Pangea. Mites now live on flowering plants, but their ancient counterparts must have stayed on trees.
The ancient mites, according to the Associated Press, have been named Triasacarus fedelei and Ampezzoa triassica.
Derek Briggs, director of the Yale Peabody Museum of Natural History and who wasn't part of the research, called the bugs' discovery tantalizing, adding that it could help researchers further understand how life evolved on land.