Recent studies indicate that the eukaryotic cell evolved from the inside-out, forming intracellular spaces by slowly enclosing them.
Eukaryotic cells, cells which have a nucleus and membrane bound organelles, define the class of living organisms which includes all plants and animals. The evolution of eukaryotic cells has become widely regarded as one of the most important steps in the development of life as we know it. Nevertheless, it is still poorly understood.
Previous models for eukaryotic cell evolution were mostly based upon the theory that precursors for nuclear and organelle structures evolved within the cytoplasm of a prokaryotic cell. However, recent studies indicate that the eukaryotic cell might have evolved from the inside-out. A prokaryotic cell, which would become the modern day nucleus, developed membrane blebs that extended away into the environment, forming the first organelle-like structures. These membrane blebs could interact with proto-mitochondria structures and the environment through material exchange. This would become the beginning of the spatial organisation of distinct roles.
This image was inspired by research by Buzz Baum.