Prof. Kirschvink has originated several such ideas aimed at increasing our understanding of how biological evolution has influenced, and has been influenced by, major events on the surface of the Earth. In more-or-less chronological order, the major contributions include: (1) the idea that biogenic magnetite produced by the magnetotactic bacteria ("magnetofossils") might be responsible for the magnetization of some sedimentarty rocks; these magnetofossils now provide the strongest evidence for early life on the planet Mars. (2) Another major idea is that the magnetic field sensitivity in animals might be due to small chains of the same biogenic magnetite functioning as specialized sensory organelles; this work has provided a solid biophysical basis for understanding magnetic effects on animal behavior, and has actually led to the discovery of these new sensory organs in higher animals. (3) An idea that is generating much interest recently is that the entire Earth may have actually frozen over several times in Earth history, resembling a "Snowball", potentially causing some of the most severe criseses is history of life on Earth and perhaps stimulating evolution. (4) Another original concept is that the Cambrian Evolutionary explosion may have been precipitated in part by large burst of true polar wander, in which the Earth's rotational axis moved to the equator in a geologically short interval to of time, and (5) that the burst of biomineralization observed in the fossil record at the Cambrian Explosion may have resulted from the evolutionary exaptation of the magnetite biomineralization system.