Over time, those single-celled organisms were able to evolve into multicellular life ... were quite visible once the mouse ...

Solid black circles indicate major lineages composed entirely of unicellular species. Other groups shown contain only multicellular species (solid red), some multicellular and some unicellular ...

Throughout the history of life on Earth, multicellular life evolved from single cells numerous times, but explaining how this happened is one of the major evolutionary puzzles of our time.

They believe a greatly reduced amount of the sun's warmth reached the planet's surface as solar radiation bounced off the white ... other multicellular organisms were identified in the black ...