California Academy of Sciences - To Explore, Explain, and Protect the Natural World

Charles E. Griswold

Associate Curator
Department of Entomology

Schlinger Curator of Arachnids and Myriapods. B.Sc (1972), M.Sc. (1977) and Ph.D. (1983) University of California, Berkeley; Chairman, Department of Arachnology, Natal Museum (1983-1986); Kalbfleisch Research Fellow, American Museum of Natural History (1987-1988); Smithsonian Postdoctoral Fellow (1988-1991); Research Entomologist, Smithsonian (1992); Assistant Curator, California Academy of Sciences (1992-1994); Associate Curator (1994- ); Chairman, Department of Entomology (1994-98); American Arachnological Society, Director (1991-93); Centre International de Documentation Arachnologique: USA correspondent, International Society of Arachnology (1992-), Vice President (1995-1998); Society of Systematic Biology, Editorial Board (1992-1994); Willi Hennig Society (Fellow, 1989-), Fellow, California Academy of Sciences.

Spiders are useful models for the study of evolution. Their webs, which in some species combine several kinds of silk having radically different properties, serve as tangible records of their behavior. Spider venoms are diverse, and typically have highly specific effects on the nervous systems of their victims, making venoms useful tools for students of neurophysiology. Spiders were among the first animals to emerge from the sea, and their ancient lineages may preserve biogeographic patterns that reflect the climates, ecology, and geography of the past. Their evolution can be understood through phylogenetics, that branch of the science of Systematics concerned with discovering and summarizing the pattern of evolutionary history and common ancestry among species, expressed as a cladogram (a genealogy of species). My research uses phylogenetics, particularly toward answering the questions: How many spider species are there? How, where and when did they evolve? How are their behaviors adaptive? Why do they live where they live (and not where they don't)?

Classification. -- As a graduate student at Berkeley I studied Habronattus, a genus of small, graceful jumping spiders with nearly 100 species in North America. Then I turned my attention to the higher classification of major groups of spiders, including the Haplogynae (including the common daddy-long-legs spiders and the dreaded brown recluse), Lycosoidea (wolf spiders and their kin), and Orbiculariae (orb-web builders and descendants), the latter study encompassing some of the largest and smallest of spiders and including the common garden spiders and black widows. I am currently working on the classification of all true spiders (Araneomorphae) focussing on the most primitive members of major groups. This work utilizes data from my fieldwork in North and South America, Eurasia, Africa, Australia and New Zealand. I am also monographing the Cyatholipidae, which are sheet web builders from Africa, Australia, and New Zealand, and the Zorocratidae, which are ambushers and running hunters from Africa, south Asia, and South America, and Migidae (tree trap door spiders) from Madagascar.

Historical Biogeography. -- Insofar as earth and life have evolved together, the phylogenetic relationships among species should reflect the history of the ecosystems in which they occur. This is particularly true in the case of islands. I concentrate on African "forest islands:" moist montane habitats that differ dramatically from the surrounding hot or dry lowlands yet are similar to one another though separated by hundreds to thousands of kilometers. I have classified the spiders that occur only in such habitats (endemics), and in the course of these studies I have described more than a dozen new genera and more than 100 new species. By integrating the shared information among these classifications, I am proposing a cladogram for these forest islands. My results to date suggest that these forests are ancient, and resilient.

Web Evolution. -- The phylogenetic study of Orbiculariae (orb web builders) revealed that beautiful, conspicuous, symmetrical org is a primitive web type that has evolved down several paths through specialization and simplification into sheets, cobwebs, and other architechtures that are easily concealed.

Biodiversity. -- Quantitative sampling methods to estimate total species richness of an area play an important role in research on the global loss of biodiversity. Working with an international team of arachnologists I have sampled and compared spider species richness in forests in Europe, South America, Africa and Madagascar with the goal of compiling a world map of spider species richness.

Behavioral Ecology. -- In addition to my systematic work, I have carried out field studies on the natural history and behavioral ecology of insects and spiders, including African social spiders (Stegodyphus) and their social parasites (kleptoparasites), and of tropical American spider-hunting wasps (Trypoxylon, Sphecidae).

Griswold, C. E. & R. E. Coville. 1986. Observations on the prey and nesting biology of spider-hunting wasps of the genus Trypoxylon (Hymenoptera: Sphecidae) in Costa Rica. Proceedings of the IX

International Congress of Arachnology (Panama 1983), pp. 113-116.

Griswold, C. E. 1987a. A revision of the jumping spider genus Habronattus F. O. P. Cambridge (Araneae: Salticidae), with phenetic and cladistic analyses. University of California Publications in Entomology, 107: i-ix, 1-344.

Griswold, C. E. 1987b. The African members of the trap-door spider family Migidae (Araneae: Mygalomorphae), I: The genus Moggridgea O. P. Cambridge, 1875. Annals of the Natal Museum, 28: 1-118.

Griswold, C. E. & T. Meikle Griswold. 1987. Archaeodictyna ulova new species, (Araneae: Dictynidae), a remarkable kleptoparasite of group-living eresid spiders (Stegodyphus spp., Araneae: Eresidae). American Museum Novitates, 2897: 1-11.

Griswold, C. E. 1991. Cladistic Biogeography of Afromontane Spiders. Australian Systematic Botany, 4(1): 73-89.

Coddington, J. A., C. E. Griswold, D. Silva-Dávila, E. Peñaranda, and S. Larcher. 1991. Designing and testing sampling protocols to estimate biodiversity in tropical ecosystems. Pp. 44-60 In: Dudley, E. C., (ed.) The Unity of Evolutionary Biology. Proceedings of the Fourth International Congress of Systematic and Evolutionary Biology. Dioscorides Press: Portland, Ore.

Griswold, C. E. 1993. Investigations into the phylogeny of the Lycosoid spiders and their kin (Arachnida, Araneae, Lycosoidea). Smithsonian Contributions to Zoology, 539: 1--39.

Griswold, C., J. Coddington, G. Hormiga, and N. Scharff. 1998. Phylogeny of the orb web building spiders (Araneae, Orbicularae: Deinopoidea, Araneoidea). Zoological Journal of the Linnean Society 122: 1-99.

Griswold, C., J. Coddington, N. Platnick, and R. Forster. (in press). Towards a phylogeny of entelegyne spiders (Araneae, Opisthothele, Araneomorphae). Journal of Arachnology 27.