On the waning relevance of bug-based work in paleoceanography. (NOTA BREVE)

BOLTOVSKOY DEMETRIO

Radiolaria (Newsletter of the International Association of Radiolarian Paleontologists)

International Association of Radiolarian Paleontologists

Lugar: New York; Año: 1994 vol. 14 p. 4 - 5

0009-6733

Are faunal/floral approaches to stratigraphic-paleoceano­graphic surveys an extinguishing species? I thought at first that this feeling was only my biased appreciation of the sit­uation, but talking to people and scanning through presenta­tions during the last few years´ meetings reinforced my feel­ing that, in effect, fewer and fewer people make slides and look at the bugs. Moreover, many of the few that used to identify species are switching to putting shells in vials and running chemical analyses on them. Carbon and, especially, oxygen isotopes are THE DATA that use up to 70-80% of the poster space and oral presentation time in todays congresses. Usefulness of this information, fast acquisition of impres­sive numbers of data points, ease of comparison with litera­ture data, are some of the advantages that made isotope stud­ies so popular. I think, however, that one of the major fac­tors that contributed to the decline in the interest for sur­veys based on species identifications is our inability to work out a common language as far as the names and shapes of the bugs we deal with are concerned. Some years ago, we (Boltovskoy & Jankilevich) compared the results of our rad identifi­cations in a small plankton col­lection from the equatorial Pacific ocean with publications based on materials that un­doubtedly exceeded our coverage several-fold [Oceanologica Acta, 8:101-123, 1985]. Only Petrushevskaya´s reports seemed to include all the species that we found, while the remaining 8 studies analyzed re­ported 88% to as little as 18% of our taxa. I have very little doubt that the missing radiolarians were present in their collec­tions: they were either ignored, or lumped with other forms, or split to the point one cannot trace equiva­lences. I am not implying that we were right and all the oth­ers were wrong, but just pointing out that we did not commu­nicate. There ob­viously was a language problem. When looking at the illustration of a "new" species just pub­lished in the literature, didn´t you sometimes have the "deja vue" feeling? Well, I´ve had it quite often, and sometimes, just for fun, I´d go to Haeckel or Popofsky or some other old monograph... and there it is! with horns, spines, and every­thing! Creating a "new" taxon is much much easier than comb­ing all the dusty books in search of an adequate name for the odd shell one comes across in the slide. And since too few reviewers seem to care much the new name makes its way into print and con­tributes its sand grain to the already hectic mess. Unfortunately, the process of erecting new names has practi­cally no rules to it. One just sends the manuscript; if it is lucky enough as to be reviewed by someone who cares little about nomenclature and systematics, the paper gets published and the new names are formally valid thereafter. Is there anything that can be done to mitigate this problem? In my opinion - yes. Good identifications are obviously the starting point, but then we all think that our own identifi­cations are good. But what about other people´s identifi­cations? Yes, we can definitely criticize those, or at least some of them. Look, for example, at Paulian Dumitrica´s ap­proach at describing new taxa (e.g., Revista Espa¤ola de Mi­cropaleontolog¡a, 21:207-264, 1989); I doubt that any of us would dare to question his work. Each new species is illus­trated in photographs, line drawings, thin-sections, thor­oughly described and compared with related morphotypes. And then check other descriptions of new taxa (no, I won´t give examples: we all have some good examples to offer any­way...). I have the feeling that avoiding spurious new species is as much a responsibility of the author, as it is of the referees and of the editors. When acting as referees, we should proba­bly require some minimum standards for accepting a new species from a colleague. These minima should take into ac­count the number of specimens used (measured, photographed, thin-sectioned) for the erection of the new taxon, the li­terature checked in search of synonyms, the variability within the taxon and similarities with other species, etc., etc. This problem is not a recent one: Ernst Haeckel, in his 1887 (Challenger) monograph, included 3389 radiolarian species, 2785 of which were described as new. Nowadays we are all aware of the fact that quite a few of these taxa are syn­onyms, but at the turn of the century there were no isotopes to compete with. Cathy Nigrini and Ted Moore´s 1979 radiolar­ian guide (A guide to Modern Radiolaria, Cushman Foundation for Foraminiferal Research, Special Publication 16) was a cornerstone that did a lot for improving our communication as far as radiolarian names and shapes are concerned. But the decade elapsed since that work requires a new similar effort to put some order in radiolarian taxonomy. A Nigrini-Petru­shevskaya-Dumitrica (as a biologist I am restricting my scope to Cenozoic radiolarians) coauthored updated guide would be an epoch-making update.