Distribution of deleterious mutational effects (DDME)

Three different possible types of DDMEs as computed from DNA diversity data in the fruitflies Drosophila miranda and D. pseudoobscura. The lognormal distribution is the only one that can explain the observed numbers of lethal mutations (right axis). The normal DDME could not even explain the observed diversity data (best possible fit shown). The vertical grey line marks the border to effective neutrality (Nes = 0.5 with Ne = 837000). For more details, see Loewe & Charlesworth (2006, http://www.journals.royalsoc.ac.uk/openurl.asp?genre=article&issn=1744-9561&volume=2&issue=3&spage=426).

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