Edited by Maureen O’Malley and Yan Boucher, the series brings together articles that showcase new methodological and conceptual developments in regard to the Tree of Life and its phylogenetic legacy.

Introducing the series, Koonin and O’Malley examine the original Tree of Life hypothesis and heuristic in light of recent discoveries. The series currently features insights into the prokaryote-eukaryote divide (Lane), the challenges faced with generating and interpreting a tree or network of all genomes (Beiko), and a review of three major transitions in early evolution when considered without a Tree of Life (Martin).

In a thought-provoking opinion piece, Kutschera also presents a novel perspective on macroevolution in proposing a tree-like "symbiogenesis, natural selection, and dynamic Earth (synade)-model".

Irrespective of whether these new approaches modify or reject the traditional Tree of Life model, the articles in the series illustrate the “wealth of insight gained by thinking beyond a central icon of evolutionary biology”, O’Malley states.

This series has been published as part of the ‘Questioning the Tree of Life’ project supported by the Leverhulme Trust. This was one of a number of exciting projects coinciding with Darwin year in 2009. Other projects included the Wellcome Trust’s ‘Interactive’ Tree of Life allowing you to visualize the evolutionary links between living things on earth.

Further articles will be added to the series soon; to be notified when they are published, please sign up for article alerts.