Did Mendel "cheat" ?
Mendel's data has led to speculation about the accuracy and
completeness of his reported results, and led to a perennial
Did Mendel Cheat?
(1) Statistical analysis of the
reported in Mendel's 1866 paper suggest they are "too good:"
conform more closely to the predicted 3:1 ratio than would be
given the number of observations. This has led to suggestions
Mendel selectively presented only those data that best
hypothesis, or even fabricated the data outright. An
explanation is that Mendel may have observed a ratio close to
early counts, and thereafter continued counting until he felt
that a genuine 3:1 had been obtained. Researchers nowadays
pre-determine the number of seeds to be counted, but such
sophistication was not available in the the 1860s.
with seven genes, and Pisum
pairs of chromosomes. It is highly improbable that seven
randomly-chosen genes would each occur on a separate
Dihybrid crosses involving genes on the same chromosome would
have shown linkage,
would have been unexplainable by Mendel's
chromosomes were unknown in the 1860s].
Therefore, it is
must have thrown out some dihybrid results
that didn't fit his rules.
In fact, the seven genes map to only four
chromosomes, and only two of these are close enough to
disequilibrium. Since there are (7)(7-1)/2
= 21 possible dihybrid
crosses, and Mendel reported results from only a few of these
including the linked pair), there is no basis on which to
accuracy and completeness of his dihybrid results.