Mark E. Siddall is a Canadian biologist and former curator[1] at the American Museum of Natural History. Siddall has studied the evolution and systematics of blood parasites and leeches, and systematic theory[2].[citation needed] Siddall was hired as an assistant curator at the American Museum of Natural History in July, 1999[3] and worked there as a curator until September, 2020, when he was terminated for allegedly having violated the museum's policy prohibiting sexual relationships between staff and mentees. Siddall denied the claim.[1]
Siddall completed a Masters[4] and PhD[5] under the supervision of Sherwin S. Desser at the University of Toronto in 1991 and 1994, respectively.[6]
After completing his PhD, Siddall completed a postdoc at the Virginia Institute of Marine Science.[7] Subsequently, he was a fellow in the Michigan Society of Fellows from 1996-1999.[8] He also acted as treasurer of the Willi Hennig Society, publisher of the journal Cladistics.[9]
Siddall has worked and published on parasitic and other animals, including leeches,[10] jellyfish,[11] guinea worms,[12] and bed bugs.[13][14]
He is author of the science book Poison: Sinister Species with Deadly Consequences.[15]
In 2016, Siddall, Jonathan Eisen, and others were involved in the Twitter controversy #ParsimonyGate.[9]
The American Museum of Natural History fired Siddall in September 2020 for alleged sexual harassment, citing museum policy that prohibits sexual relationships between staff and mentees under their academic supervision.[1] An outside law firm representing the museum's interests found that Siddall had "engaged in verbal, written, and physical conduct of a sexual nature that had the effect of unreasonably interfering with your academic performance."[1] Siddall denied that any sexual encounter ever took place, and claimed he was fired because "he had found a serious error" in a paper.[1]
Siddall studies phylogenetics and evolution.[10] Siddall has been described as "a staunch supporter of parsimony and a harsh critic of maximum likelihood approaches”, although "having mellowed a bit on that".[7]