Taxonomy
Imagining, creating & naming seemingly related groups of cowries

Cowries can't read; they don't always meet to our expectations.

The cowry shown at the left was in an article published in the Hawaiian Shell News as "An Unexpected Pair of Cowries" (Sept. 1990, VOL. XXXVII, NEW SERIES 369, pg. 10). It was collected from the waters of the North Shore area, Oahu, Hawaii, in the early '90s. At present it has to be called Cypraea sp. (something between a C. nucleus and a C. granulata) and was video-taped the following day, along with its 'mate' and several other cowries found on that particular night dive. To view that article, click here.
If the reader has had any contact with the branch of science called taxonomy, then the opening quote on this page should speak volumes about the trials and tribulations experienced by taxonomists. Had Shakespeare's Hamlet been a taxonomist, he could have replaced "to be" with "to name" and little of the drama would have been lost.
(NOTE: The following is not intended as a "scientific" presentation...
but that does not imply it lacks merit. )

As mentioned elsewhere in these pages, C. sulcidentata and C. schilderorum often mingle (or re-mingle) their genetic material. The immediate result is a specimen that is distinctive enough to have a semi-firm price among Hawaiian shell dealers—$50 for a high quality specimen. [Click here to see many examples of these ‘in-between’ shells.] That's a good price for a single specimen and many x-breeds of this type have been sold off, to sit stashed away in some private collection. That's one less for the powers-that-be to worry about having to explain. (In this writer's opinion, a blind eye is coveniently turned toward the ‘half-breeds,’ ‘crossbreeds,’ and ‘throwbacks’ which have littered, and continue to litter, the collections of local shellers. It is all rather messy and best avoided by any who might become stressed about explaining just what is going on. But crossbreeds still happen—regularly. The granulata x nucleus specimen displayed above, and in an HSN article republished in these pages, is a rare catch but there are more common 'variants' to amuse oneself with.)

This author has been of the opinion for many years that several of the cowries listed as species today might best be described as ‘varieties’ or ‘breeds’ (as in breeds of dogs, except that we have no control over the breeding of cowries). In Hawaii (and other locales), the Cypraea teres complex is an excellent representation (again, in this author's opinion) of intergradation between two widely distributed species of cowry; the other of the two species being Cypraea cernica Linnaeus. Originally thought to be endemic to the Hawaiian Islands, species like C. rashleighana, C. “burgessi,” and C. “alisonae” began to be collected all over the Pacific, even on the southwest coast of Australia. There was a lot of head-scratching over ‘how-in-the-world’ veligers could make that long trip, settle out, and grow to maturity so far from their native waters.

Of course, the veligers were locally generated by conjunctions, perhaps only one, between teres and cernica. Due to brooding tendencies discussed elsewhere in these pages (Malacology) there is a strong chance of interbreeding and backbreeding thus the by-products of these unions could be many different mixtures of the parents' traits. Here this writer must use that terrible, even accursed, word that sends shivers down many a sheller's spine.... genetics. Yes, cowries have genes. How many genes, on how many chromosomes? Somebody possibly knows but the exact number is not pertinent at this point.

What's important is that virtually every aspect of the animal and its shell, which together comprise a cowry, is an expression of genetic material. Some sections of genetic material are on the same chromosome and sort out together most of the time during meiosis. Other pieces––representing different aspects of shell shape, coloration, patterning––may be located on separate chromosomes and get shuffled around and mixed quite a bit. AND, some traits may be due to dominant genes, some due to recessive genes, and others multi-locus genes. Start thinking about the many possible combinations of dominant, recessive and multi-locus genes on the same chromosome or on separate chromosomes and the mind begins to stagger under the load. Then throw in chiasmata, or crossings-over, and the reader might get an idea why Mendel 'fudged' his research data on the sweet pea. He knew how it should be but he had not correctly deduced the way Nature really functioned. In the end, we must determine how Nature actually goes about its business, comprehending also that we do not dictate to Nature which groups are species and which are not.
(continued in next issue)

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