Anything personal you want to tell the rest of the community?
Change of address, new job title, some other exciting news?
Mail it to the People Editor.
Role Models in Nematology
Dr. Johannes Govertus de Man (1850-1930),
a Dutch pioneer of Nematode Taxonomy
Dr. Johannes Govertus de Man, a remarkable Dutch zoologist
who lived from 1850 up to 1930, devoted his life to the
science of systematics on Crustacea and Nematoda. Johannes,
or Jan as he was usually named, was born at Middelburg,
province of Zeeland in the South West of the Netherlands,
on May 2nd 1850.
As a young boy already, he developed a strong interest
in biology and loved to collect insects. From 1868-1873
he studied at the University of Leiden, the Netherlands,
where he obtained his masters degree in 1871 and his doctors
degree (magna cum lauda) in 1873. From 1872 till 1883 he
worked as invertebrate curator at the National Museum of
Natural History at Leiden on the systematics of both the
Crustacea, in particular on the Decapoda (i.e. crabs, crayfish,
lobsters and shrimps), and the microscopic small roundworms
or Nematoda. In 1883 Jan resigned at the museum, but continued
working on Decapoda and Nematoda first at his parents' house
(1883-1893) at Middelburg and later on at his own house
in Yerseke, the Netherlands (1893-1930), up to his death
on January 19, 1930.
Besides his important contribution to Crustacea taxonomy
- he described 30 Crustacea genera and 523 new Crustacea
species (including 7 Stomatopoda) - he is worldwide known
in Nematology for the introduction of 8 new families, 61
new genera and 239 new species including animal parasites,
plant parasites and free-living terrestrial and aquatic
nematodes. He produced high quality monographs on soil,
plant and freshwater nematodes. In total J.G. de Man published
181 articles and monographic papers, most of them on Crustacea
and Nematoda, but also some papers on Turbellaria (free-living
flatworms), Mollusca (shells) and Sipunculida (peanut worms).
During his life J.G. de Man became known not only as an
excellent specialist of worldwide reputation on Decapoda
but also as one of the founders and pioneers within Nematology.
For both invertebrate groups he is not only known, because
of the quantity of his work, but also particularly for the
high quality of the descriptions often liberally illustrated
with excellent drawings. In 1880, J.G. de Man introduced
a formula now known as body ratios a (body length divided
by maximum body width), b (body length divided by oesophageal/pharyngeal
length), c ( body length divided by tail length) for measuring
nematodes. The demanian formula is till today universally
used in nematode taxonomy. J.G de Man can without doubt
be considered as a role model for nematology and more specifically
for nematode taxonomy.
More inspiring information on his life and contributions
to science and Nematology in particular can be found in:
- Karssen, G. (2006). Life and work of Dr. J.G. de Man,
a Crustacea and Nematoda specialist. Brill Leiden, the Netherlands.
120p. (ISBN-10: 90 0414 9694, ISBN-13: 978 90 0414 969 4).
- Nematode in the picture:
with courtesy from Dr Gerrit Karssen and Dr Hans Helder