Controversies 7 Goss(1824)studied cotyledon color and described dominance, as well as segregatio although in purely qualitative terms Seton(1824)studied stem length and cotyledon color Gartner(1849) reviewed Knight's work with seed coat color, and described his own work n Pisum with stem length, flower color, cotyledon color, and seed shape Mendel studied Gartner's(1849)book on plant hybridization in detail before and during his experiments, as he indicated in his first letter to Nageli and as evidenced by his 17 references in Thus, he was familiar with both Knight's and Gartner's pea hybridization experiments The type of analysis that Mendel conducted relies on traits that display discontinuous variation, as does detection of linkage. The traits that Mendel chose to study are among only a few that varied in a discontinuous fashion among commercially available 19g century varieties Mendel's varieties certainly differed in more than the seven traits on which he reported o For example, he also reported in his paper that he conducted experiments on the timing of flowering, peduncle length, and brownish-red pod color but he did not report the data for these experiments o However, most of the other traits display continuous variation and are governed y multiple genes and environmental influences and cannot be easily analyzed in a simple Mendelian fashion Mendel's choice of traits apparently was based o first on those studied by his predecessors and o second on those that had distinct discontinuous phenotypic differences that permitted conclusive analysis Fairbanks and Rytting(2001) concluded "because of the locations of the genes that governed such traits and the design of his experiments, it is unlikely that he could have detected linkage. There is no botanical or historical evidence to support the claim that Mendel observed and then disregarded linkage Did Mendel support or oppose Darwin? Mendel was clearly interested in evolution and he considered his experiments as relevant to an understanding of evolutio At the time Mendel wrote his paper, the Origin was well known and evolution through natural selection was a popular topic for discussion in scientific societies According to Orel (1971, 1996), Mendel probably first heard of Darwin in September 1861 during a lecture. He might have read the Origin during the latter part of 1862 or early 1863 when the brunn Natural History Society acquired a copy of the German translation of the first English edition(Darwin, 1859). The 1863 publication date of Mendel's personal copy of the Origin coincides with the last year of his experiments with peasControversies 7 • Goss (1824) studied cotyledon color and described dominance, as well as segregation, although in purely qualitative terms. • Seton (1824) studied stem length and cotyledon color. • Gärtner (1849) reviewed Knight's work with seed coat color, and described his own work in Pisum with stem length, flower color, cotyledon color, and seed shape. Mendel studied Gärtner's (1849) book on plant hybridization in detail before and during his experiments, as he indicated in his first letter to Nägeli and as evidenced by his 17 references in his paper. Thus, he was familiar with both Knight's and Gärtner's pea hybridization experiments. • The type of analysis that Mendel conducted relies on traits that display discontinuous variation, as does detection of linkage. The traits that Mendel chose to study are among only a few that varied in a discontinuous fashion among commercially available 19th century varieties. • Mendel's varieties certainly differed in more than the seven traits on which he reported data. o For example, he also reported in his paper that he conducted experiments on the timing of flowering, peduncle length, and brownish-red pod color but he did not report the data for these experiments. o However, most of the other traits display continuous variation and are governed by multiple genes and environmental influences and cannot be easily analyzed in a simple Mendelian fashion. Mendel's choice of traits apparently was based: o first on those studied by his predecessors and, o second on those that had distinct discontinuous phenotypic differences that permitted conclusive analysis. Fairbanks and Rytting (2001) concluded “because of the locations of the genes that governed such traits and the design of his experiments, it is unlikely that he could have detected linkage. There is no botanical or historical evidence to support the claim that Mendel observed and then disregarded linkage.” Did Mendel support or oppose Darwin? Mendel was clearly interested in evolution and he considered his experiments as relevant to an understanding of evolution. At the time Mendel wrote his paper, the Origin was well known and evolution through natural selection was a popular topic for discussion in scientific societies. • According to Orel (1971, 1996), Mendel probably first heard of Darwin in September 1861 during a lecture. He might have read the Origin during the latter part of 1862 or early 1863 when the Brünn Natural History Society acquired a copy of the German translation of the first English edition (Darwin, 1859). The 1863 publication date of Mendel's personal copy of the Origin coincides with the last year of his experiments with peas