Carl Rettenmeyer

Carl W. Rettenmeyer (February 10, 1931 – April 9, 2009) was an American biologist who specialised in army ants. He was born in Meriden, Connecticut, and later attended Swarthmore College in Pennsylvania. He first became interested in army ants when he visited Panama as an undergraduate and then returned there as a postgraduate. Although he studied many aspects of army ant biology, he particularly focused on the animals associated with the ants and especially mites which live on the ants. He was well known for his photography of army ants, with his photographs appearing in over 100 publications, and he used his video footage to create two DVDs. He taught at the University of Kansas from 1960 until 1971 and then at the University of Connecticut until his retirement in 1996, after being diagnosed with Waldenstrom’s macroglobulinemia. After his death in 2009, a set of papers on army ants were published in Insectes Sociaux in memory of his work.

Personal life Rettenmeyer was born in Meriden, Connecticut, to his parents Frederick and Gertrude; he had one sister. Together they had a son and a daughter. a new drug developed soon after his diagnosis kept the disease in check, allowing him to continue to work, despite often having to use a wheelchair due to his frailty.

Education Rettenmeyer attended Swarthmore College as an undergraduate, majoring in Biology and graduated in 1953.

After graduating he studied a PhD in entomology at the University of Kansas under the supervision of Charles Duncan Michener, which he completed in 1962. During his PhD Life magazine approached him asking him to accompany a photographer to BCI to photograph army ants. Rettenmeyer says that this was his "lucky break" and during nine weeks spent on BCI he collected thousands of specimens, including 147 species of mite found living on the ants. Upon his return to Kansas he was encouraged by faculty members to apply for funding so he could return to study army ants in the rainforest. Through his career he went on over 20 expeditions to Panama, Ecuador and Costa Rica.

In 1963, Rettenmeyer rediscovered the army ant Neivamyrmex sumichrasti, which was first scientifically described by François Sumichrast in the 1860s but then not studied further. In 2003, he helped another expedition find the species again, and also tried to find a species of beetle associated with it. However, Ecitosius robustus, the robust army ant beetle, is almost impossible to distinguish physically from the host ant, and Rettenmeyer was unable to find it among the samples collected.

Working with his wife, Rettenmeyer identified 557 species of animals associated with Eciton burchellii, the greatest number of animals known to associate with any single animal species. Although many of the associations are likely to be opportunistic, over 300 species are thought to be reliant on the ant to survive. As well as these species, Rettenmeyer collected many thousands of specimens that have not been identified. He spent his later years examining samples from 1,600 army ant colonies he had collected and in total found 45,000 mites. Of these mites, only 3% have been studied and whilst doing so, three new mite families were identified as well as over 100 new species. Those identified often have inconceivably strange lifestyles. Another mite only lives on the eye of another species and Rettenmeyerius carli lives on the base of worker's mandibles.

After his death a set of papers on army ants were published in Insectes Sociaux in memory of his work.

Photography Rettenmeyer was known for his ability to photograph previously unseen aspects of army ant behaviour and his photographs appeared in National Geographic, the Audubon Encyclopedia of Wildlife, National Wildlife Federation, and Smithsonian magazine. Among his accomplishments was photographing army ants mating for the first time, as well as estimating the longevity of the queen by recapturing a specimen. He continued as the director until his retirement.