Project Summary

Transformative developments in bioinformatics and Next Generation Sequencing (NGS) are making it possible to map the spatial and temporal layout of the Earth's biota in unprecedented detail. Project ADMAC will advance this goal by applying the latest techniques to the ants of the MesoAmerican corridor. The proposed study capitalizes on a previously-funded project (PROJECT LLAMA) that thoroughly sampled ant diversity in the region, revealing distributional patterns at the species level. This new project will: (1) apply NGS methods to both phylogeny reconstruction and species delimitation, (2) test hypotheses about the evolution and assembly of tropical montane biotas, (3) reveal biogeographic history at the contact zone of two major continents, (4) greatly improve taxonomic infrastructure for an ecologically and economically important insect taxon, (5) provide a model for other insect systematics projects that can use NGS, and (6) communicate the excitement and importance of these developments to a broad student and public audience.

The MesoAmerican corridor, a young land-bridge connecting North and South America, is a zone of intense biogeographical interest. The corridor's mountains show a great range of ages, from tens of thousands to tens of millions of years, raising questions about how tropical montane biotas evolve. How frequently do montane species originate from lowland ancestors, compared to subsequent diversification within montane regions? Do species form by vicariance at the time of mountain orogeny, or by dispersal and subsequent isolation long after mountains have formed? What is the role of volcanoes that produce ephemeral montane islands? Answering these questions requires (1) multiple diverse taxa to discern repeatable patterns, (2) a clear idea of species boundaries, and (3) well-resolved species-level phylogenies. These three requirements will be satisfied by applying NGS methods to ants of the MesoAmerican corridor. This region is ideally suited to address these issues. Three major mountain regions - the Oaxaca/Veracruz highlands, the core MesoAmerican highlands from Chiapas to northern Nicaragua, and the Talamanca range in Costa Rica and Panama - are separated by lowland biogeographical barriers. The two northern regions are old (uplifted starting 70 mya), while the Talamanca range is young (uplifted abruptly 3-5 mya). Isolated dormant or active volcanoes dot the landscape, many capped by cloud forests. Ants are a dominant feature of the landscape, have thousands of species in the region, and show high levels of elevational specialization. NGS methods allow thousands of samples to be sequenced for many hundreds of loci, and analytical techniques are being developed to use these data for both species delimitation and phylogeny reconstruction at multiple time depths. The Leaf Litter Arthropods of MesoAmerica project (LLAMA, DEB-0640015/1157383) carried out intensive, quantitative ant sampling at 34 sites, evenly distributed from Nicaragua to southern Mexico, yielding more than 600 species in over 62,000 taxon occurrences, with 78 new species described during the project. The material is all less than five years old and ready for immediate sequencing. During the new project an efficient NGS pipeline will be established to sequence 6,000 specimens, carry out new field sampling in the Oaxaca and Veracruz highlands and the Talamanca range (key regions that flank the LLAMA samples), provide complete phylogenies and taxonomic revisions for 13 clades (>290 species) with centers of diversity in MesoAmerica, and provide species delimitation and alpha-taxonomic products for traditionally complex and diverse genera.

Development of NGS methods for species delimitation and phylogeny reconstruction could revolutionize taxonomy and systematics, with consequent benefits to other fields of science, agriculture, food inspection, public health, and invasive species detection. Improved understanding of the origin of montane biotas and zones of endemism within MesoAmerica is relevant to conservation efforts and gauging the impacts of habitat conversion and climate change. Training in biodiversity science will occur at graduate and undergraduate levels at two public universities. Partnering with the Natural History Museum of Utah will achieve outreach and science recruiting goals among undergraduates and the broader public, with emphasis on underserved groups and quantifiable assessment of outreach activities.