title: Phylogenomic Insights into the Evolution of Stinging Wasps and the Origins of Ants and Bees.
abstract: The stinging wasps (Hymenoptera: Aculeata) are an extremely diverse lineage of hymenopteran insects, encompassing over 70,000 described species and a diversity of life history traits, including ectoparasitism, cleptoparasitism, predation, pollen feeding (bees [Anthophila] and Masarinae), and eusociality (social vespid wasps, ants, and some bees) [1]. The most well-studied lineages of Aculeata are the ants, which are ecologically dominant in most terrestrial ecosystems [2], and the bees, the most important lineage of angiosperm-pollinating insects [3]. Establishing the phylogenetic affinities of ants and bees helps us understand and reconstruct patterns of social evolution as well as fully appreciate the biological implications of the switch from carnivory to pollen feeding (pollenivory). Despite recent advancements in aculeate phylogeny [4-11], considerable uncertainty remains regarding higher-level relationships within Aculeata, including the phylogenetic affinities of ants and bees [5-7]. We used ultraconserved element (UCE) phylogenomics [7, 12] to resolve relationships among stinging-wasp families, gathering sequence data from >800 UCE loci and 187 samples, including 30 out of 31 aculeate families. We analyzed the 187-taxon dataset using multiple analytical approaches, and we evaluated several alternative taxon sets. We also tested alternative hypotheses for the phylogenetic positions of ants and bees. Our results present a highly supported phylogeny of the stinging wasps. Most importantly, we find unequivocal evidence that ants are the sister group to bees+apoid wasps (Apoidea) and that bees are nested within a paraphyletic Crabronidae. We also demonstrate that taxon choice can fundamentally impact tree topology and clade support in phylogenomic inference.
authors.affiliation: Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA; Department of Entomology, National Museum of Natural History, Smithsonian Institution, PO Box 37012, 10(th) Street and Constitution Avenue NW, Washington, DC 20560, USA. Electronic address: mgbranstetter@gmail.com.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Branstetter
authors.affiliation: Department of Entomology, 3119 Comstock Hall, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Bryan N
authors.initials: BN
authors.lastname: Danforth
authors.affiliation: Department of Biology, Utah State University, 5305 Old Main Hill, Logan, UT 84322-5305, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Pitts
authors.affiliation: Department of Biological Sciences and Museum of Natural Science, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Brant C
authors.initials: BC
authors.lastname: Faircloth
authors.affiliation: Department of Entomology and Nematology, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA.
authors.forename: Philip S
authors.initials: PS
authors.lastname: Ward
authors.affiliation: Systematic Entomology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, US Department of Agriculture, c/o Department of Entomology, National Museum of Natural History, Smithsonian Institution, PO Box 37012, 10(th) Street and Constitution Avenue NW, Washington, DC 20560, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Buffington
authors.affiliation: Systematic Entomology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, US Department of Agriculture, c/o Department of Entomology, National Museum of Natural History, Smithsonian Institution, PO Box 37012, 10(th) Street and Constitution Avenue NW, Washington, DC 20560, USA.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Gates
authors.affiliation: Systematic Entomology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, US Department of Agriculture, c/o Department of Entomology, National Museum of Natural History, Smithsonian Institution, PO Box 37012, 10(th) Street and Constitution Avenue NW, Washington, DC 20560, USA.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Kula
authors.affiliation: Department of Entomology, National Museum of Natural History, Smithsonian Institution, PO Box 37012, 10(th) Street and Constitution Avenue NW, Washington, DC 20560, USA.
authors.forename: Seán G
authors.initials: SG
authors.lastname: Brady
mesh_terms: D000818:Animals; D001000:Ants / Q000145:classification / Q000235:genetics*; D001516:Bees / Q000145:classification / Q000235:genetics*; D005075:Biological Evolution; D019143:Evolution, Molecular; D049750:Genome, Insect; D010802:Phylogeny; D014863:Wasps / Q000145:classification / Q000235:genetics*
keywords: Aculeata; Hymenoptera; molecular systematics; next-generation sequencing; phylogenomics; social insects; taxon sampling; ultraconserved elements