Scientists Unearth Oldest Fossil of Mating Bugs

Scientists in China have unearthed the oldest fossil of copulating insects in the north-eastern region of the country. The fossil is believed to be 165 million years old.

It is very unusual to find fossils depicting any sort of mating action. Chinese scientists were highly lucky to find a fossil of copulating insects. The extraordinary find reveals that the genital symmetry and mating position hasn't changed over the last 165 million years for froghoppers that hop from plant to plant like tiny frogs.

The never-before-seen well preserved fossil of the two froghoppers (Anthoscytina perpetua) clearly show belly to belly mating position. It shows how the male reproductive organ called the aedeagus is clearly inserted into the female's reproductive organ called the bursa copulatrix. The abdomen of the fossilized male insect is twisted for better penetration. This position of mating is even seen in the modern day insects. The froghoppers mate either face to face or side by side on a leaf or tree trunk, reportsLiveScience.

 Dong Ren at the Capital Normal University in China said in a statement, "We found these two very rare copulating froghoppers which provide a glimpse of interesting insect behavior and important data to understand their mating position and genitalia orientation during the Middle Jurassic."

Scientists believe that the insects that were in the middle of copulating when they were struck by poisonous gas from volcanic eruption, reports the The Sydney Morning Herald. This gas killed all life and maybe the insects were later blown by the wind into a nearby lake and they sank to the bottom.  Gradually the duo was covered by layers of sediments that preserved them for ages. The fossil is now treasured in the insect fossil collection in Beijing.  

"This one is so rare," said Chungkun Shih, a visiting professor at the university and one of the authors of the paper. "I got involved in this research in 1999, and I have seen more than half a million fossils, but this was the only one in which the insects were clearly mating."

He added that generally such fossils of insects are trapped in amber and are extremely rare to find. Till date only 40 have been found around the world. But this is the oldest fossil that shows the insect's genitalia clearly and dates back to the mid Jurassic period.

This finding enhances the current knowledge of mating positions and genitalia orientation in the early stages of evolution.

The details have been documented in the journal PLOS ONE.