Historical Development of Chromosome Theory

The chromosomal theory did not appear all at once; it was assembled from a run of careful cytological observations spread across two decades. Wilhelm Roux, as early as 1883, was the first to suggest that the chromosomes seen inside a dividing cell might be the actual agents responsible for transmitting heredity, well before anyone could prove it. Thomas Montgomery, in 1901, went further and showed that chromosomes exist as distinct pairs, and crucially that during meiosis a maternally derived chromosome always pairs specifically with its paternal counterpart, never with an unrelated one. Theodor Boveri, working at almost the same time, supplied strong experimental support for the idea that chromosomes actually carry the hereditary determiners, and he is credited as one of the two principal architects of the theory. Independently, in 1902, the young American student Walter Sutton noticed a striking parallel between how chromosomes behave during gamete formation and how Mendel's abstract factors were inferred to behave, and he made that parallel explicit. In 1903, Sutton and Boveri, worki …