Michael Pyshnov

Michael Pyshnov is a Canadian scientist who contributed to the area of the origination of organismal form. In the early 1980's he conducted pioneering research at the University of Toronto on the development of organs in the Drosophila fruit fly. He discovered that what was previously thought to be unorganised mass of embryonic cells (called "imaginal discs" in larvae), in fact possesses peculiar cell arrangements specific for future organs. And that, therefore, the so-called "positional information" for the structure of future organs is encoded in the cell arrangements of embryonic tissue. Michael Pyshnov discovered the material basis of embryogenesis at the cellular level. He also discovered that a mutation that causes embryonic tissue normally producing one organ (antenna) to produce a different organ (a leg), is actually changing the pattern of cell arrangement in the embryonic tissue. Moreover, he earlier predicted all of this on the basis of his previous theoretical work.