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Ants have remarkably diverse diets and extraordinary species richness, making them an excellent model system to study the evolution of taste. In this entirely eusocial clade, food choice and the mechanisms that regulate feeding have both individual and social dimensions. How taste receptors and sensory processing drive food preferences to generate dietary breadth in ants is poorly understood. It is additionally unclear how elements of colony organization such as division of labor and social food flow impact the mechanistic basis and evolution of taste. Previous work on dipteran, lepidopteran, and hymenopteran gustatory systems, while foundational, provide limited insights into ant dietary specialization. Here we synthesize and analyze research on ant gustation to identify mechanisms, sociobiological correlates, and phylogenetic patterns. We discuss the current state of genomic analyses of taste and future research. We propose that strikingly polymorphic species of Pheidole , Cephalotes , Camponotus , and leafcutter ants ( Atta and Acromyrmex ) offer compelling social systems to explore adaptive variation in gustation because of their pronounced division of labor in which morphologically, behaviorally, and neurally differentiated workers vary in feeding behavior. Research on ant gustation within and among species will advance our understanding of sensory systems and provide insight into the impact of taste on the evolution of species diversity and how social organization influences gustation.
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The first fossil replete ant worker establishes living food storage in the Eocene
Worker specialization extends the behavioral and ecological repertoire of ant colonies. Specialization may relate to colony defense, brood care, foraging, and, in some taxa, storage. Replete workers swell the crop and gaster to store liquid food, which can be accessed by other colony members through trophallaxis. This storage ability, known as repletism, has in- dependently evolved across several ant lineages, but the temporal history of this trait has not yet been investigated. Here, we describe the first fossil replete in the extinct species Leptomyrmex neotropicus Baroni Urbani, 1980 preserved in Miocene-age Dominican amber. Together with new evidence of repletism in L. neotropicus’ extant sister species, Lep- tomyrmex relictus Boudinot & al., 2016, we reconstruct the pattern of acquisition and descent in this storage-linked trait. Our ancestral-state reconstruction suggests that Leptomyrmex acquired replete workers in the Eocene and may therefore represent the earliest instance of so-called “honeypot” ants among all known ants, both living and extinct.
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- Award ID(s):
- 2144915
- PAR ID:
- 10439179
- Date Published:
- Journal Name:
- Myrmecological news
- Volume:
- 33
- ISSN:
- 1994-4136
- Page Range / eLocation ID:
- 139-147
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1101/2022.12.15.520604
