DNA barcoding

DNA barcoding is an approach to specimen identification and biodiversity assessment achieved through the use of orthologous DNA sequences. It can be used on live, killed, fragmentary, museum, fixed, and even unseen organisms. It may be the only realistic way of assessing true biodiversity (species numbers and phylogenetic diversity) of meio- and micro-scale organisms, such as nematodes.

MOTU is an acronym we invented in the late 1990's to describe the clusters of specimens we were defining based on sequence identity (see here for the original text). A search of online multilingual dictionaries however, revealed that the phoneme has been used for millenia by peoples of the Pacific, where, spookily, it almost means the same thing: to cut off (or define) and an islet (or cluster). Most entertainingly, the word is also used in the context of writing or inscribing, the giving-physical-name-to-things (see below). The image is of one of the few extant carved wooden panels inscribed with the language of Easter Island.

motu (definition in Easter Island)

1. to cut; to snap off: motu-á te hau, the fishing line snapped off; to engrave, to inscribe letters or pictures in stone or in wood, like the motu mo rogorogo, inscriptions for recitation in lines called kohau.

2. islet; some names of islets: Motu Motiro Hiva, Sala y Gómez; and around the island: Motu Nui, Motu Iti, Motu Kaokao, Motu Tapu, Motu Marotiri, Motu Kau, Motu Tavake, Motu Tautara, Motu Ko Hepa Ko Maihori, Motu Hava.

see here for our original definition of Molecular Operational Taxonomic Units or MOTU, as posted on the www in 1999

see here for our MOTU inference software package MOTU_define.pl

Barcoding Nematodes, Tardigrades and other Meiofauna

We are using molecular methods to perform surveys of nematode and other meiofaunal biodiversity in terrestrial and marine habitats. This work builds from our interest in nematode molecular phylogenetics and an enthusiasm for neglected meiobeasts.

	what	why	who
	The M-OTU concept	Using molecular markers to define taxa	Robin Floyd, Eyualem Abebe and Mark Blaxter
	nematode population genetics	a website collating information on molecular methods for nematode population genetics and diversity studies	Barbara Wimmer and Mark Blaxter
	MOTU applied to the terrestrial nematodes of Sourhope Farm	As part of the NERC soil biodiversity and ecosystem function programme we are analysing nematode diversity on a test site in southern Scotland	Robin Floyd, Eyualem Abebe and Mark Blaxter
	MOTU applied to marine nematodes	We have performed preliminary surveys of marine nematode diversity in Scotland using the MOTU method.	Robin Floyd, Eyualem Abebe and Mark Blaxter
	Nematode Phylogenetic Diversity	Using molecular markers to analyse the diversity of the Phylum Nematoda	Mark Blaxter