Thomas Cavalier-Smith

Professor Thomas (Tom) Cavalier-Smith (born October 21 1942), FRS, FRSC, NERC Professorial Fellow, is a Professor of Evolutionary Biology in the Department of Zoology, at the University of Oxford. He was presented with the International Prize for Biology (a prize of 10 million yen) in 2004.

Cavalier-Smith has published extensively on the classification of protists. One of his major contributions to biology was his proposal of a sixth kingdom of life: the Chromista, although the evidence for the existence of the group is still open to debate. He also proposed that all chromista and alveolata share the same common ancestor, a claim later supported by studies of morphological and molecular evidence by other labs. He named this new group the Chromalveolates. It is also he who proposed and named many other high-rank taxa, like Opisthokonta (1987), Rhizaria (2002) or Excavata (2002). Together with Chromalveolata, Amoebozoa (he emended their description in 1998) and Archaeplastida (which he called Plantae since 1981) the six form the basis of current taxonomy of eukaryotes. Prof. Cavalier-Smith has also published prodigiously on issues such as the origin of various cellular organelles (including the nucleus, mitochondria), genome size evolution, and endosymbiosis. Though fairly well known, many of his strongest claims have been controversial and have not gained widespread acceptance in the scientific community to date.

Most recently, he has published a paper citing the paraphyly of the bacterial domain, and the origin of Neomura from Actinobacteria.