Thursday, April 15, 2010

Ancient Cockroach Ancestor in 3D

X-ray micro-tomography of Carboniferous stem-Dictyoptera: new insights into early insects. 2010. R. Garwood and M.Sutton. Biology Letters.

Archimylacris eggintoni
, an early ancestor of the cockroach has been unveiled in unprecedented detail in a new three-dimensional 'virtual fossil' model. This insect scuttled around on Earth during the Carboniferous period 359 - 299 million years ago, which was a time when life had recently emerged from the oceans to live on land.

The 3D model also reveals how Archimylacris eggintoni's legs could help it to run fast. The team noted that the legs were at a low angle to the body and fairly long, which they believe helped it to move quickly even when the terrain was difficult or uneven.

It also had sticky structures on its legs called euplantulae to help them stick to smooth surfaces such as leaves as they climbed across them.

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.

Mr Garwood adds: "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."