Tuesday, 19 March 2019


The other day, one of my project students was looking more competent than me [red face] in the tools of his/our trade. In too much of a hurry, I thought that Proboscia was essentially the same as Proboscidea. When I slowwwwwed down I twigged that one Proboscia is about 50μm on length while elephants are about about 100,000x longer trunk-to-tail. What a difference a '...de...' makes! The accident tinkled a distant bell that there were pairs of species which really did have the same name but were completely different.

A recent explanation of the rules and regs for the naming of parts in biology is The use and limits of scientific names in biological informatics by David Remsen Zookeys. 2016; (550): 207–223.  It's something that requires a certain amount of precision to prevent misunderstanding. If you want to communicate some measurements blue-tit [the bird in the picture] wings to your colleagues in Hungary then using a universal [dead] language prevents ambiguity: Cyanistes caeruleus is the only thing it could be I would be skeptical about using the Google - Magyar translate to kék cinege. Not a big problem in this example because the bird appears on both the EN and HU versions of wikipedia. But what about something more obscure: the White-bellied rice-rat Oryzomys albiventer isn't in hu.wikipedia.

One of the rules about taxonomy is naming priority. 25 years ago, I had a heart-in-boots moment on that front. We'd just published a sequence analysis paper on Aspergillus nidulans. and I thought I'd check the database to see if there were any new A. nidulans sequences which I could add to our tiny dataset. When I asked, ACNUC (the then cutting edge database interrogation software) came back with No Sequences Found. It was like arriving at the 13th Floor by elevator in an episode of The Twilight Zone. As Aspergillus nidulans is a widely studied standard genetic organism like lab mouse Mus musculus and Drosophila melanogaster, it wasn't just me who was hopping mad disconcerted. The naming people at GenBank had been following priority rules to rename the species as Emericella nidulans. Luckily they were pragmatists rather than pedants and, at the next full release of GenBank three months later, all my Aspergillus sequences were back on line.

The key element of nomenclature is to be unambiguous. If things are different they get different names. Careful analysis [bloboprev] of the biology and biogeography of giraffes Giraffa giraffa made experts believe that there were really 9 different species of long-necks in Africa and they all needed a separate species name. The names of animals are decided / approved by ICZN; a different body to the ICN namers of plants fungi and algae.
Partly from the inertia of the system; partly because the two entities are unambiguous different there are an least half a dozen hemihomonyms: species which have the same official Linnaean monnicker. Here [L] is a nice pair, both Agathis montana: LL is a braconid wasp widely distributed across Eurasia from Korea to UK. LR is a long-lived conifer from New Caledonia in the far east.  It is critically endangered from a perfect storm of bark-beetles delivering fungal disease, feral pigs, and habitat destruction from climate change and logging. That extinction will nicely tidy up the taxonomic conundrum, no? Here are the other hemihomonymous pairs acknowledged by wikipedia:
venomous fish
another fish
That's only the top of the iceberg, however, Алексей Шипунов from Russia has compiled a mighty database of hemihomonyms - including 12 examples where a Genus is triplicated in bacteria, plants and animals:  Catenococcus  Gordonia  Kingella  Lawsonia  Leptonema  Microcyclus  Moorella  Morganella  Rhodococcus  Rothia  Spirulina  Stenocybe.

Because these worthy taxonomy-mavens are aware of illiteracy, dyslexia and Latinophobia among those who need to know the Names of Life, there is another class of wrong-wrong-almost-right called parahomonyms which are at best discouraged if not absolutely verboten.  Thus Astrostemma Benth. 1880 has been rejected in favour of Absolmia Kuntze; because it was too much like Asterostemma Decne. 1838 another genus of plants in the same family. To crowd confusion on ambiguity Asterostemma depressa is a fossil mammal from Argentina.

A couple of years ago I was laying out a very similar problem with the naming of drugs: where errors are more likely to kills people than mistakes

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