Monday, January 13, 2014

CHT Townsend, Vandal of the Calypterates. Part I.

I've received a lot of feedback about my post about Call to Comments. Most of it has been considerate and helpful. There was one case of a sockpuppet by a certain someone, but it's no matter.

What does bother me is it seems like people are interpreting the post to be about the Spracklandus case when it isn't. I used the background of that case as an example, a dispute containing both bad taxonomy and thrown insults, something which has been happening since the beginning of nomenclature. I also used it because I find nomenclature fascinating, to the point where I lay away at night thinking about the ins and outs of the Code. And, because I love taxonomy, and history, and because the recentness of this case meant it was well cataloged. 

But I could have used any number of historical disputes, including the focus of this series, Charles Henry Tyler Townsend, or CHT Townsend for short.

I am not, unlike in Neal Evenhuis's excellent and overly kind biography of the man (found in this issue of Fly Times), going to recount Townsend's life. Instead, I'm going to focus on his controversial work with calypterate flies, and how in many ways he left things worse than when he started.

Townsend's chosen group, those true flies belonging to the monophyletic lineage Calypterata, contains common insects such as the house fly (Muscidae), flesh flies (Sarcophagidae), and blue bottle flies (Calliphoridae), as well as the less common but more horrific bot flies (Oestridae). But the most diverse calypterate group are the tachinids, estimated to be the largest group of Diptera surpassing even crane fly (Tipulidae) species numbers.

Dr. Townsend chose these flies as his specialty, particularly tachinids. By the time of his doctorate on calypterate female physiology (1914), he was pouring himself into the work that would eventually become the Manual of Myiology (1936-1941). That many volume set of keys and descriptions is still used today when dealing with the South American fauna.

Unfortunately, Townsend was unconventional or downright radical when it came to his taxonomy. Monty Wood of the Canadian National Collection, a world expert on tachinid flies, told me Townsend's work and opinions were simply an example of his ego and arrogance. The problem that set South American tachinid taxonomy back a century stem from one particular issue, his species concept, which lead to his tendency to split taxa ad infinitum.

In his history of tachinid fly classification, Jim O'Hara writes,

"The restricted genera of Townsend were based on the author’s concept of a “physiological genus”, defined as a “natural genus” comprising “all those species which can produce fertile crosses” (Townsend 1935: 38). As noted by van Emden (1945: 389–390), “the adoption of [this] principle implies the application of the generic unit to every unit considered to be a species in general zoological practice”. One can learn, explained Townsend (1935: 56), “to make a complete description of a fly genus and its genotype [type species] in one hour for one sex and an hour and a half for both sexes”. The ideal number of members within each of the categories of genus, tribe, family, suborder and order was set at five (Townsend 1935: 60–61). In practise Townsend rarely included more than one species per genus and throughout his career described 1491 genera and 1555 species (Arnaud 1958), with approximately 85% of the genera belonging to the Tachinidae."

 In other words, 95% of his genera were monospecific.

My current work with tachinids is not my first contact with Townsend's modus operandi. In one of his Insect Morphology lectures, Peter Adler of Clemson University would recount this strange methodology, saying that a difference in structure indicated a new genus, and a difference in color meant a new species. Townsend recorded all this information on index cards in a card filing system. Whenever he found something he considered new, he would reference the system, and fill out a new card. He also had a tendency to split the higher classification, leading to a grand total of 7 families and ~90 tribes of the current Tachinidae. This volume of new taxa matches what we would today consider to be taxonomic vandalism. It did not help matters that his descriptions were much like others of the day, paragraph length and lacking any illustrations. His keys, both in the Manual of Myiology and his Synopse dos generos muscoideos da regiao humida tropical da America (1927), were not much better; they are hundreds of couplets long and practically unusable, yet necessary works when wading through the vast fauna of the Neotropics.

Other tachinid workers reacted much in the same way you would expect: they synonymized names. In particular, this was a drawn out feud between Townsend and John Merton Aldrich, a prolific Diptera taxonomist and Associate Curator of Insects at the US National Museum from 1918 until his death in 1934.

It's not clear when the argument started. By the time Aldrich published his catalog of North American Diptera (1905), Townsend had published 84 papers on true flies. This list of publications fills up 6 pages of the catalog, more than any other author. He comments on one, writing, "An attempt to interpret Van der Wulp's too brief diagnoses, without the material to throw any particular light on them; an altogether superfluous piece of meddling. The changes of generic names are both uncalled for." He also calls attention to Townsend's strict following of Brauer and Bergenstaumm genera, yet praises Townsend for his species descriptions, writing, "The specific descriptions of Townsend are conscientious and faithful, and among the most recognizable of any in the family."

There were obviously no hard feelings at this point, but over the next 20 years their relationship of shared interest would become seriously strained by Townsend's public and often unprofessional reactions to Aldrich's work, and vice versa.

Continued in Part II.

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