British scientists have unveiled an early ancestor of the cockroach which they claim lived 300 million years ago, in a new 3D “virtual fossil” model.
A team at Imperial College London has, in fact, made a comprehensive 3D model of fossilised specimen Archimylacris eggintoni, which is an ancient ancestor of modern cockroaches, mantises and termites, the ‘Biology Letters’ journal.
This insect scuttled around on Earth during the Carboniferous period 359 to 299 million years ago, which was a time when life had recently emerged from the oceans to live on land, the scientists say.
Their study reveals for the first time how Archimylacris eggintoni’s physical traits helped it to thrive on the floor of Earth’s early forests. The fossils of these creatures are normally between 2cm and 9cm in length and approximately 4cm in width.
Lead scientist Russell Garwood said: “The Carboniferous period is sometimes referred to as the age of the cockroach because fossils of Archimylacris eggintoni and its relatives are amongst the most common insects from this time period. They are found all over the world.
“People joke about it being impossible to kill cockroaches and our 3D model almost brings this one back to life. Thanks to our 3D modelling process, we can see how Archimylacris eggintoni’s limbs were well adapted for all terrains, as it was not only adept in the air but also very agile on the ground.”
The scientists created their images using a CT scanning device, based at the Natural History Museum in London, which enabled them to take 3142 x-rays of the fossil and compile the images into an accurate 3D model, creating a “virtual fossil” of the creature, using a special software.
They used the models to visualise the Archimylacris eggintoni’s legs, antennae, mouth parts and body, which had never been seen by human eyes before.
In their study, the scientists’ computer model reveals that Archimylacris eggintoni had sticky structures on its legs called euplantulae.
They believe the euplantulae enabled Archimylacris eggintoni to stick to smooth surfaces such as leaves as they climbed across them, which may have helped them to lay their eggs above the ground in safer locations away from predators.
In addition, the scientists also discovered that Archimylacris eggintoni had claws at the base of its legs, which helped it to climb rough surfaces like trees, so that it could perch above the forest floor for safety or find alternate sources of food higher up.
“We now think this ancient ancestor of the cockroach spent most of the day on the forest floor, living in and eating lots of rotting plant and insect matter, which was probably the bug equivalent of heaven.
“We think it could have used its speed to evade predators and its climbing abilities to scale trees and lay eggs on leaves, much in the same way that modern forest cockroaches do today,” Garwood said.
