Fossils provide important clues into a world long before humans. They allow us to see not only the kinds of organisms that lived millions of years ago, but it also provides insight into the evolutionary trajectory of life on earth. With fossils, we can see dramatic changes in life and learn about the evolution of certain biological features.
However, a lack of fossils in certain time periods can make it challenging to piece together the entire story.
In a new study published in Papers in Paleontology, researchers at the Spanish Geological Survey describe a fossil that, until only recently, was recorded as being one of the oldest fossils of a dipteran, or a group of insects that include flies, mosquitoes, and gnats. The fossil in question dates to almost 250 million years ago, before the time of even the earliest dinosaurs. Analysis of the fossil sheds some light on how these insects adapted following the mass extinction event that took out nearly 80 percent of all species on the planet.
The fossil was discovered in the Balearic Islands in Spain, which has long been a source of interest for paleontologists. Ripe with fossilized remains of a number of creatures, including plants and crustaceans, the area provides deep insight into a world almost 250 million years ago, right around the time that a cataclysmic event led to the extinction of the dinosaurs.
According the team, a close analysis of the fossil revealed a well-preserved anatomy, including structures like the head, digestive tract, and even its respiratory system.
The discovery of the fossil also helps fill in some critical gaps in understand about this time period. For example, its well known that dipterans had to create new ecologies and roles in these systems following the mass extinction event, though because of a poor fossil record, understanding these adaptations has been difficult. In fact, the presence of this fossil and its well-preserved structure allowed researchers to ascertain that “it [the larvae] represents the only known Triassic dipteran larva with terrestrial affinities indicating that the amphipneustic respiratory system of insect larvae extends” about 247 million years in the past.
Sources: Eurekalert!; Papers in Paleontology