Colonial lives

Hoyt, Eric.1996. The Earth Dwellers: Adventures in the Land of the Ants. New York. Simon and Schuster. 319pp.

Excellent book about ants at La Selva, the Organization for Tropical Studies’ field station in Costa Rica, both because it describes several species of very different ants from an ant’s eye view and for the endearing descriptions of two great myrmecologists, Bill Brown and E.O. Wilson, at work together in the field. Wilson is known to almost everyone, but Brown was also one of the greatest entomologists of the last century. Their contrasting personalities make them like characters from a movie about the adventures of two mismatched buddies. I was amused and edified by Hoyt’s description of their field techniques and sometimes reckless determination in the search for the miracle ant, Thaumatomyrmex. Brown’s views on taxonomic and systematic work, described here, are worth considering, and it is also worthwhile to look up his and Wilson’s published papers. Hoyt includes interesting biographical accounts of both men and quite a lot of readable information on the biology and evolution of ants and ants’ social behavior.

Wilson, E.O. and Jose M. Gomez Duran. 2010. Kingdom of Ants. Jose Celestino Mutis and the Dawn of Natural History in the New World. Baltimore. Johns Hopkins University Press. 96 pp.

Jose Celestino Mutis spent over forty years as a physician, botanist, linguist and priest in what is now Colombia (when he arrived from Spain in 1761, it was the New Kingdom of Granada). He began studying ants at the suggestion of Linnaeus, whose system he used in his work on plants. His detailed reports on ants are apparently lost, but this little book contains long quotes from his journals, which give accounts of his studies several species, including leaf cutter and army ants. Every aspiring naturalist should study these notes to appreciate Mutis’s clarity, perseverance and, above all, skepticism and honesty. This is best shown in the passages where he explains how he realized that the big-headed “soldier” ants were not the males, but instead, when he finally was able to observe copulation, males turned out to be the small winged individuals, who he originally took for young females, not fully grown. He expresses his gratitude to God for enabling him to correct his error and make such a wonderful discovery. In another entry, he reproaches himself for letting the press of his experiments on smelting metals in the mines cause him to forget to follow up on a potentially valuable observation. Another day, he forgets to record part of what he saw, and so with reservation, he allows himself to write it down the next day. He constantly refers to the need to check his conjectures with more observations and to try to reconfirm what others report to him. He often asks the local farmers for their views, but he never accepts them without the evidence of his own eyes. When he tries to estimate the number of army ants in a colony, he uses several independent methods of arriving at the number. As Wilson and Duran point out, about all you could wish of him is a naturalist is that he had included sketches of his ants to help modern myrmecologists identify them. They wonder why he did not do for ants what he did for plants: fit them into Linneaus’ system and have illustrations prepared. Despite owning a huge library, he was evidently not aware of Maria Sibylla Merian’s work on insects in Surinam or any published works on ants. He was quite on his own, with no prior experience and no expert to guide him when he began his work at age twenty-eight. Linnaeus had named only a handful of ants, all in one genus and with very sketchy descriptions. Although Mutis’s descriptions show him to be clear sighted, he does not attempt any sort of systematic classification of the species he encounters, based for example, on the number of petiole segments or the presence of a sting in the workers. This job was left to later workers. His greatest contributions were to the study of ants’ social behavior. He was without doubt one of the finest scientists of the 18th century. Perhaps only von Humboldt equals him as an observer. On the 200th anniversary of his death, the Colombian myrmecologist, Fernando Fernández and E.O. Wilson, named a new ant species, Pheidole mutisi (Fernández, F.; Wilson, E. O. 2008. José Celestino Mutis, the ants, and Pheidole mutisi sp. nov. Revista Colombiana de Entomología 34:203-208). 

Thanks to Wilson and Duran for making this gem available to naturalists.

Rau, Phil and Nellie Rau. 1918. Wasp Studies Afield. Princeton, NJ. Princeton University Press. 372 pp. [Dover Books reprint]

This is a fascinating early twentieth century work on solitary and social wasps. The Raus carried out their studies in the midwestern U.S. Their research covered hunting wasps with a wide range of prey. The wasps included both soil and wood nesting species in diverse habitats; one even dug in the clay infield of a baseball diamond. The Raus made detailed behavioural observations on many species and did experiments on paper wasp homing ability. They mention the drop off in aggression by paper wasps as winter approaches, all the brood matures and the workers die off and are replaced by overwintering queens. That’s just one example of many behaviors that I have noticed but not really thought about until they described it. Another good read for anyone who aspires to study insects in the field.

Neotropical travellers

Essay on the Geography of Plants, by Alexander von Humboldt, and Aimee Bonpland. 2009 (1807). Edited by Stephen Jackson. Translated by Sylvie Romanowski. University of Chicago Press. Chicago. 274 pp with tableau in pocket
This book is pure descriptive natural history, with almost no speculation or discussion of causes. It is divided into Humboldt’s Essay of some 30 or 40 pages and the longer Tableau Physique prepared by Humboldt and Bonpland. Some of Von Humboldt’s fascinations, like barometric pressure, which he includes along with temperature, humidity and “electrical tension” as factors influencing plant distribution, seem peculiar to me, but I have to remember that he was much more limited in what he could measure than we are today. Another peculiarity is his notion of “social” plants, by which he seems to mean those that form dense monocultures as opposed to mixed stands. He says these live “in organized society, like ants and bees…” His examples include mangroves, Cladonia lichens and pines, but also Vaccinium. He notes that such plants are more common in the temperate regions than in the tropics. Mexico is an exception, harboring many temperate species, like pine, oak and sweet gum, which he attributes in part to the vast geographical expanse of the northern part of America, narrowing southwards. Somehow this causes Mexico to be colder than similar latitudes elsewhere. Then there is his idea of “subterranean vegetation,” which seems to mean fungi in caves and mines. He treats these “cryptograms,” alongside lichens and mosses. How aware was he of the fundamental distinction between autotrophs and heterotrophs? Photosynthesis was barely beginning to be understood in his time.
He also lacked a clear notion of geologic time, referring only to remote ages, but with no clear sense of the scope and significance of the fossil record. Only the epoch of human spread across the earth is accessible to his reflections on the distribution of plants. When compared to Graham’s Natural History of the New World, he has far less to go on, and barely any sense of the potential of fossils to shed light on modern plant communities and their distributions. Yet Graham clearly is following in the footsteps of von Humboldt and Bonpland.
One advance he makes is to point out the importance of physiognomy alongside taxonomy in describing communities of plants (another of his ideas) what we today commonly call life forms or growth forms.
The main thing, though, is the Tableau Physique, the profile of the Andes, using the volcano Chimborazo thought, at the time, to be the highest peak in the world. The detailed data packed into a single illustration is startling and quite beautiful. The other wonderful part is his concluding reflections in the essay on the value of natural history writing and artwork in elevating and liberating our understanding, even if we cannot experience these amazing places directly.