For centuries, there has been speculation about whether there is any life on our nearest planet Mars. After all, there are those ‘canals’ and there is some kind of atmosphere.<\/p>\n\n\n\n
Of course, it depends how you define “life” and, believe it or not, there is no absolutely agreed definition, but the American space agency NASA has a good working description: \u201ca self sustaining chemical system capable of Darwinian evolution\u201d.<\/p>\n\n\n\n
On this basis, there may be no life on Mars – but maybe we should have a broader definition.<\/p>\n\n\n\n
Stuart Bartlett, a complexity scientist at Caltech, and Michael L Wong, an astrobiologist at the University of Washington, have developed a new hypothetical concept: lyfe.<\/p>\n\n\n\n
They define a \u201clyving\u201d organism as satisfying four criteria: dissipation (the ability to harness and convert free energy sources); autocatalysis (the ability to grow or expand exponentially); homeostasis (the ability to limit change internally when things change externally); and learning (the ability to record, process and carry out actions based on information).<\/p>\n\n\n\n
With this definition, life is just one specific instance of lyfe and there could be a higher probability of finding lyfe – rather than life – on Mars.<\/p>\n\n\n\n