Richard Owen's Catalogues : An Enduring Legacy  (2007.6.1[Fri])

 

I thought I would devote this installment of the Library News to a book in the CDB Library that helped give our lab a publication.

 When I first came to Kobe, I was a member of the Library Committee and when we began working to set the Library up, Dr Aizawa told me he wanted to have a collection equal to those in national university libraries, which was a bit of a tall order for a place that still had no history or holdings to speak of, but I have to admit, it's the kind of job I don't mind doing. I started by making a list of important and notable works of anatomy, developmental biology, histology and evolutionary biology and then, with the able assistance of Ichimura-san in the CDB Library, searching antiquarian book vendors overseas and purchasing what was available. We began receiving catalogues from booksellers on a regular basis, with information on such true rarities as Conrad Gesner's Thierbuch, of which there are only perhaps 2 or 3 copies in all of Japan. Unfortunately, but predictably for such a find, that was snapped up by a collector...

 So it wasn't long before we had the beginnings of a collection, but we were still a long way from rivaling any national university. The overwhelming focus of the works is on zoology and comparative morphology, which undoubtedly reflects my own knowledge and preferences, and memories of days spent in the Kyoto University Library and, in fact, I have to say that the history of biology as I understand it is shaped by exactly these types of books. Needless to say, textbooks from later-emerging fields are of higher quality and the content has to be more up to date to be of any value. But that's not necessarily the case for comparative development and morphology, fields in which it would be impossible to create a high-quality textbook without reference to the accumulated wealth of detailed descriptions from the past (which is not to say that attempts have not been made). Thus morphologists tend to stick, faute de mieux, to the classics, just as our colleagues in natural history inevitably do. So for us, these aren't just some musty old relics, they're actually quite useful. You might even say they're the best resources we have.

 So, among that collection of books we spent so much time and effort assembling, the one that I'd like to introduce this time is the Descriptive Catalogue of the Osteological Series contained in the Museum of the Royal College of Surgeons of England (1853), which the famous British anatomist Richard Owen compiled from the enormous collection of specimens collected by the great Scottish surgeon and anatomist, John Hunter, and which resulted in Owen's appointment as superintendent of the natural history collections at the British Museum. It would take an entire book to do justice to John Hunter's achievements, as in addition to his contributions to medicine his career featured many interesting sidelights. For me at least, the life stories of Hunter and the equally weird and wonderful Owen hold much more interest than do those of Darwin and T. H. Huxley.

 And just what kind of book is the Catalogue? It's unmistakably zoology, but you won't find a single illustration within, just page after page of entries listing specimens and the basic skeletal characteristics like what types of teeth and how many of them and counts of vertebrae and digits per limb. This kind of formal expression of body organization was called the Bauplan, corresponding to what we refer to as the body plan these days, and what Owen did was none other than to describe the plans of a staggering variety of vertebrate life. For those of us interested in a comprehensive treatment of skeletal Baupläne, this is the book.

 You could also say that in a sense it's a catalogue of the diversity of developmental programs as well, as it inventories and numbers each of the different types of vertebrae in a given specimen's vertebral column (what's known as the vertebral formula), as determined by none other than the famous Hox family of regulatory genes. And that means by studying changes in the vertebral formula, you can at the same time glean insights into changes in the underlying genetic code. Which is exactly what I was thinking when I suggested to Yuichi Narita, a postdoc in my lab, that he might try aligning Owen's vertebral formulae with a phylogenetic tree-not one of the trees available to Owen in the 19th century mind you, but one based on the high confidence levels afforded by the most recent molecular data. (The science of taxonomy was built on a foundation of comparative morphology, so any attempt to compare something like the vertebral formula against a classical categorization scheme would be an essay in tautology.) What we were hoping to do was to make changes in developmental routines visible through their phylogenetic influences. You could say that we were relying on other peoplefs data, and though bringing them up to modern standards was no easy thing, Yuichi really threw himself into it and did an excellent job.

 It's been known for a long time that mammals nearly universally have seven cervical vertebrae, while the numbers of thoracic and lumbar vertebrae seem to vary by species. But it soon became apparent that in many mammals, the sum of these two types of vertebrae is usually 19, and this is true not only for the eutherians, but their sister groups the pouched marsupials (metatherians) and egg-laying monotremes (prototherians) as well. This magic number is conserved in many orders and superclasses and appears to have become established as a new rule after some evolutionary divergence. The vertebral formula is not subject to random change; rather, a change in a developmental mechanism gave rise to a new scheme (or Bauplan) to which other new rules could then be appended. Once we accept that evolution is actually the record of changes in developmental programs, it becomes clear that the history of these changes is codified in taxonomic groups.

 And that is the tale of how we found the seeds of a new publication form one of the old works in the CDB Library, a tale that indeed has an epilogue, relating to the clade Afrotheria, a superorder with impeccable molecular credentials that includes hyraxes, elephants, dugongs, tenrecs and golden moles, which first emerged in Africa and later underwent such extensive morphological diversification that, with almost no shared anatomical traits, it probably would never have been identified if not for the molecular evidence. But when Marcelo Sánchez-Villagra was here at the CDB for an entirely different reason, he noticed on one of Narita's posters that the A frotherians shared an increased total number of thoracic and lumbar vertebrae. A morphological trait for the Afrotherians at last! That was the second paper directly attributable to Sir Richard's catalogue. He's a hero to me, the next time I'm in England I'll have to pay my respects at his grave...

Narita, Y. and Kuratani, S. (2005) J. Exp. Zool. (Mol. Dev. Evol.) 304B, 91-106
Sánchez-Villagra et al. (2006 in press). Systematics and Biodiversity. (Cambridge University Press)

Reference:”Descriptive Catalogue of the Osteological Series contained in the Museum of the Royal College of Surgeons of England