title: Does exogenic food benefit both partners in an ant-plant mutualism? The case of Cecropia obtusa and its guest Azteca plant-ants.
abstract: In the mutualisms involving the myrmecophyte Cecropia obtusa and Azteca ovaticeps or A. alfari, both predatory, the ants defend their host trees from enemies and provide them with nutrients (myrmecotrophy). A. ovaticeps provisioned with prey and then (15)N-enriched food produced more individuals than did control colonies (not artificially provisioned). This was not true for A. alfari colonies, possibly due to differences in the degree of maturity of the colonies for the chosen range of host tree sizes (less than 3m in height). Myrmecotrophy was demonstrated for both Azteca species as provisioning the ants with (15)N-enriched food translated into higher δ(15)N values in host plant tissues, indicating that nitrogen passed from the food to the plant. Thus, the predatory activity of their guest ants benefits the Cecropia trees not only because the ants protect them from defoliators since most prey are phytophagous insects but also because the plant absorbs nutrients.
authors.affiliation: CNRS, écologie des forêts de Guyane (UMR-CNRS 8172), Kourou cedex, France. alain.dejean@wanadoo.fr
authors.forename: Alain
authors.initials: A
authors.lastname: Dejean
authors.forename: Frédéric
authors.initials: F
authors.lastname: Petitclerc
authors.forename: Olivier
authors.initials: O
authors.lastname: Roux
authors.forename: Jérôme
authors.initials: J
authors.lastname: Orivel
authors.forename: Céline
authors.initials: C
authors.lastname: Leroy
mesh_terms: D000818:Animals; D001000:Ants / Q000502:physiology*; D035702:Cecropia Plant / Q000502:physiology*; D005260:Female; D005502:Food; D007814:Larva; D008297:Male; D009124:Muscle Proteins / Q000096:biosynthesis; D009132:Muscles / Q000502:physiology; D009587:Nitrogen Isotopes; D009747:Nutritional Physiological Phenomena; D018515:Plant Leaves / Q000737:chemistry; D011158:Population Growth; D011235:Predatory Behavior; D013559:Symbiosis / Q000502:physiology*; D014197:Trees
chemical_list: D009124:Muscle Proteins; D009587:Nitrogen Isotopes