Diagram of proteins from a unicellular organism called Haloferax volcanii
Francisco J. Enguita/Science Photo Library
When certain unicellular microorganisms are compressed, they develop into multicellular tissue-like structures containing many different types of cells. This suggests that pressure may help promote important evolutionary leaps, such as the emergence of multicellularity.
This organism is a type of archaea, one of the three realms of life along with bacteria and eukaryotes. Eukaryotes are organisms that have cells that contain a nucleus and include animals and plants. Because archaea do not have a nucleus, they were initially mistaken for bacteria, but are now considered bacteria.
