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Any comprehensive theory of organismal form must relate the short-term processes of embryonic development to the long-term processes of evolutionary change—in what Mayr (1982, 1994, 1997) termed "internal" and "external" biology; see Mayr and Provine (1980) and Hall (1998) for overviews. Any integration of internal and external biology involves a synthesis, or at the very least a coming together, of developmental and evolutionary biology as Evolutionary Developmental Biology (Hall, 1998). Hence, a symposium on Developmental and Evolutionary Perspectives on Major Transformations in Body Organization, the selection of approaches and speakers, and the venue—the Society for Integrative and Comparative Biology. Although attempts to understand the processes and mechanisms underlying body organization have been made for millennia, two periods of particularly intense research activity stand out. The first, in the latter half of the 19th century, was characterized by the discovery that all animals are built from similar cells, tissues and organs; that these cells arise embryologically from the same germ layers; that embryos of very different organisms progress through surprisingly similar stages using similar developmental processes of cell division, migration, commitment, differentiation and morphogenesis (see Bowler, 1996; Gee, 1996 and Hall, 1998 for reviews). Still, embryos, larvae and adults of dif

The current theory of felid coat pattern evolution proposes that the primitive pattern is one of relatively large spots that break down into smaller spots (here denoted flecks) and rosettes while at the same time leading to various striped patterns as sidelines. We have coded the coat patterns of felids into uniform, flecks, rosettes, vertical stripes, small blotches and blotches and show by mapping these character states onto phylogenies of the family that the current theory is flawed. Instead, the primitive pattern appears to be flecks and it is from this type that nearly all other types have developed. The robustness of this hypothesis is shown by the fact that it remains unchanged regardless of which of several quite different, competing phylogenies of the family is used. The pattern of transformations reconstructed is not predicted by current theories of pattern formation and we suggest that modellers pay closer attention to the phylogenetic histories of the features that they model.

Synopsis. The primitive, or ancestral reproductive mode for Recent am? phibians involves a complex, biphasic life history. Yet evolutionarily derived, alternate modes are seen in all three living orders and predominate in some clades. Analysis of the consequences and mechanistic bases of one such mode?direct development?can provide insights into the evolutionary opportunities and constraints conferred by the ancestral metamorphic ontog? eny. Direct development in the anuran genus Eleutherodactylus involves fundamental alterations to many features of embryonic and posthatching devel? opment. At hatching, young emerge as fully formed, albeit tiny versions of the adult; most larvai features are absent. Pervasive changes in ontogenetic timing, in particular the precocious (embryonic) formation of many adult structures, appear to be correlated with early development of the thyroid axis, although responsiveness to exogenous thyroid hormone is diminished or even lacking in at least some peripheral tissues. Changes in cranial patterning are likely mediated by the embryonic neural crest, although many gross features of crest biology are highly conserved. Laboratory-based analyses of direct de? velopment and other derived reproductive modes in amphibians, using contemporary methods developed for more standard, "model" organisms, may contribute important insights into life-history evolution that complement those derived from analyses of morphology, ecology and phylogeny.

The phenotypic characteristics of a cloned giant cell line, SU/RH-HD-1, established from the spleen of a patient with Hodgkin's disease were studied. The cells grew slowly, adhered to the culture vessel surface, and had an elongated, irregular shape. After trypsinization, they became spherical and measured 30-100 micron in diameter. Although most cells were mononuclear, binucleated and multinucleated cells could be identified in expanded cultures. The cells phagocytized latex and ink particles and were nonspecific esterase-positive, but they did not secrete lysozyme. They were Epstein-Barr nuclear antigen-negative, and their culture fluid supernatants were devoid of reverse transcriptase activity. Electron microscopy revealed cells with a pronounced smooth endoplasmic reticulum, free ribosomes, some filaments, and mitochondria. Many 0.5- to 1.0-micron invaginations (pits) were seen along the cell membrane. Nucleoli were enlarged and prominent in the very heterochromatic nuclei. The SU/RH-HD-1 cells had 10- to 100-micron-long pseudopodia that were sometimes forked or branching, as well as multiple stress fibers. Electron microscopic appearance was suggestive of that of macrophages. This interpretation of the results was substantiated by monoclonal antibody studies, which revealed that the cells express antigenic determinants distinctive for cells of the monocyte-macrophage lineage and by functional studies demonstrating that the cells are capable of specific antigen presentation to immune T-cells. The SU/RH-HD-1 cells were aneuploid and could be cloned, first in liquid culture by limiting dilution and later in semisolid medium. It was likely that the SU/RH-HD-1 cells were derived from the neoplastic giant cell population in Hodgkin's disease and that they originated from cells of the mononuclear phagocyte-reticulum cell lineage.