The Improbable Origin of Complex Life

Abstract: All complex (eukaryotic) life on Earth shares a common ancestor that arose just once in 4 billion years of evolution. All eukaryotes share a large number of complex morphological traits, from the nucleus to sex, none of which are known in prokaryotes. I shall argue that eukaryotes emerged from a cellular chimera, in which an archaeal host cell engulfed another bacterium, the ancestor of mitochondria, giving eukaryotes orders of magnitude more energy per gene than prokaryotes. I will discuss the singularity of eukaryotic origins: why mitochondria enabled the evolution of enormous genomic complexity, while simultaneously forcing the evolution of so many curious eukaryotic traits.

Dr Nick Lane is Reader in Evolutionary Biochemistry in the Department of Genetics, Evolution and Environment at University College London, and the author of four acclaimed books on evolution. Nick’s research deals with bioenergetics, focusing on the origin of life and the evolution of complex cells. He was a founding member of the UCL Consortium for Mitochondrial Research, and leads the UCL Research Frontiers Origins of Life programme. He was awarded the 2010 Royal Society Prize for Science Books, and the 2015 Biochemical Society Award for his outstanding contribution to molecular life sciences.

Host: Professor Bob White