Intensive work led Morgan to discover more mutant traitssome two dozen between 1911 and 1914. With evidence drawn from cytology he was able to refine Mendelian laws and combine them with the theoryfirst suggested by Theodor Boveri and Walter Suttonthat the chromosomes carry hereditary information. In 1915, Morgan and his colleagues published The Mechanism of Mendelian Heredity. Its major tenets:
His work with showed that it was necessary to have all present in order for proper development of the to take place. This discovery was an important part of the Boveri-Sutton chromosome theory. His other significant discovery was the (1888), which he described as the . Boveri also discovered the phenomenon of diminution during embryonic development of the nematode .
The Boveri-Sutton chromosome theory (also knownas the chromosome theory of inheritance) is afundamental unifying theory of which identifies as thecarrier of .It correctly explains the mechanism underlying the laws of byidentifying with the paired (particles) required byMendel's laws. It also states that chromosomes are linearstructures with located atspecific sites along them.
and independently developed thechromosome theory of inheritance in 1902.Boveri was studying , in which he found that all the chromosomes had to bepresent for proper to take place. Sutton's work with showedthat chromosomes occur in matched pairs of maternal and paternalchromosomes which separate during meiosis.