eukaryotic cell

Computer artwork of the internal structure of a eukaryotic cell, including mitochondria (red ovoids)

JUAN GAERTNER/Science Photo Library/Alamy

We may have imagined our most distant ancestor wrongly. The first complex cell may have been bigger and even more internally complex than anyone suspected – and that may have helped it survive.

Over a billion years ago, evolution gave rise to the first complex cell. It is often pictured as something like an amoeba or a white blood cell: a roughly spherical blob with a single packet of DNA at its core.

But a new study argues that is wrong. Instead, it …