Terra formars vol 0

In an attempt to colonize Mars, 21st century scientists were tasked with warming up the planet so that humans could survive on its surface. They came up with an efficient and cost effective plan of sending cockroaches and mold to the surface so that the mold would absorb the sunlight and purify the atmosphere, while feeding the insects whose corpses would help the mold spread throughout the planet.

Five hundred years later, the first manned ship to Mars lands on the planet to find.... written by Yū Sasuga and illustrated by Kenichi Tachibana (PDF copy)