 However, new analysis in the 1980s by Harry B. Whittington, Derek Briggs, Simon Conway Morris and others sparked a renewed interest and a burst of activity including discovery of an important new fossil site, Sirius Passet, in Greenland, and the publication of a popular and controversial book, "Wonderful Life" by Stephen Jay Gould in 1989.Prior to 1950 there was no widely accepted fossil evidence of life before the Cambrian period.When Charles Darwin wrote "The Origin of Species" he acknowledged that the lack of any fossil evidence of life prior to the relatively complex animals of the Cambrian was a potential argument against the theory of evolution, but expressed the hope that such fossils would be found in the future.