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Fungus-farming ants cultivate multiple lineages of fungi for food, but, because fungal cultivar relationships are largely unresolved, the history of fungus-ant coevolution remains poorly known. We designed probes targeting >2000 gene regions to generate a dated evolutionary tree for 475 fungi and combined it with a similarly generated tree for 276 ants. We found that fungus-ant agriculture originated ~66 million years ago when the end-of-Cretaceous asteroid impact temporarily interrupted photosynthesis, causing global mass extinctions but favoring the proliferation of fungi. Subsequently, ~27 million years ago, one ancestral fungal cultivar population became domesticated, i.e., obligately mutualistic, when seasonally dry habitats expanded in South America, likely isolating the cultivar population from its free-living, wet forest–dwelling conspecifics. By revealing these and other major transitions in fungus-ant coevolution, our results clarify the historical processes that shaped a model system for nonhuman agriculture.
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The Convergent Evolution of Agriculture in Humans and Insects
Contributors explore common elements in the evolutionary histories of both human and insect agriculture resulting from convergent evolution. During the past 12,000 years, agriculture originated in humans as many as twenty-three times, and during the past 65 million years, agriculture also originated in nonhuman animals at least twenty times and in insects at least fifteen times. It is much more likely that these independent origins represent similar solutions to the challenge of growing food than that they are due purely to chance. This volume seeks to identify common elements in the evolutionary histories of both human and insect agriculture that are the results of convergent evolution. The goal is to create a new, synthetic field that characterizes, quantifies, and empirically documents the evolutionary and ecological mechanisms that drive both human and nonhuman agriculture. The contributors report on the results of quantitative analyses comparing human and nonhuman agriculture; discuss evolutionary conflicts of interest between and among farmers and cultivars and how they interfere with efficiencies of agricultural symbiosis; describe in detail agriculture in termites, ambrosia beetles, and ants; and consider patterns of evolutionary convergence in different aspects of agriculture, comparing fungal parasites of ant agriculture with fungal parasites of human agriculture, analyzing the effects of agriculture on human anatomy, and tracing the similarities and differences between the evolution of agriculture in humans and in a single, relatively well-studied insect group, fungus-farming ants. Contributors Duur K. Aanen, Niels P. R. Anten, Peter H. W. Biedermann, Jacobus J. Boomsma, Laura T. Buck, Guillaume Chomicki, Tim Denham, R. Ford Denison, Dorian Q. Fuller, Richard Gawne, Nicole M. Gerardo, Thomas C. Harrington, Ana Ješovnik, Judith Korb, Chase G. Mayers, George R. McGhee, Kenneth Z. McKenna, Lumila P. Menéndez, Peter N. Peregrine, Ted R. Schultz
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- Award ID(s):
- 1927161
- PAR ID:
- 10625618
- Editor(s):
- Schultz, Ted R; Gawne, Richard; Peregrine, Peter N
- Publisher / Repository:
- The MIT Press
- Date Published:
- ISBN:
- 9780262367578
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Book:
- https://doi.org/10.7551/mitpress/13600.001.0001
