Research interests/expertise: Biology and taxonomy of parasitoid wasps (Hymenoptera), particularly the large superfamily Ichneumonoidea.

Mark joined National Museums Scotland (then the Royal Scottish Museum) in 1980 and became Keeper of Natural History (at the time just Zoology) in 1983, adding Geology to this in 1996 to become Keeper of Natural Sciences until his retirement in 2005. His time as a Research Associate since 2005 is a continuation of his research and curation activity during that period.

Mark’s research includes interests in developmental biology; faunistics, taxonomy (including describing new species) and higher classification; host associations, host repertoires and speciation; and community ecology. Mark’s research is centred on the fauna of the Western Palaearctic Region and he collaborates with other specialists world-wide. The main areas of his current research are the large subfamilies Rogadinae and Microgastrinae, increasingly involving molecular (DNA) studies.

Collection-building has been a constant feature, and National Museums Scotland now holds one of the outstanding collections of European Ichneumonoidea, which is uniquely rich in specimens reared from known hosts (other insects and spiders). Partly this stems from Mark’s own fieldwork of collecting and rearing especially caterpillars, but considerable numbers of reared parasitoids have been provided by entomologists trying to rear other groups. Mark has also been given bulk non-reared parasitoid wasps arising from many field surveys of insects (typically conducted by Malaise trapping) by a variety of others, from which he has selected and mounted many tens of thousands of specimens, as well as from traps he operated himself and general collecting in the field.  Parasitic wasps collected as a by-product of moth-collecting by light have also been donated by many Lepidopterists, with notably large quantities from Sweden and the Balkans.

Because of the size and scope of the collection, it has been possible for Mark to collaborate with international specialists of particular groups (usually subfamilies) in which he has no immediate expertise to identify and catalogue parts of the collection, usually involving joint publication, invariably revealing multiple species not previously detected in Britain and often including the description of new species. Loans from the collection are frequently requested by external specialists undertaking taxonomic revisions, with the return of the specimens authentically identified. Founding a well-researched and well-curated collection of Ichneumonoidea for National Museums Scotland has always been an important part of Mark’s overall research effort.

Mark was awarded the International Society of Hymenopterists' Distinguished Research Medal in 2016 and a Marsh Award for Entomology in 2023.