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Seventh International Congress of Hymenopterists

Seventh International Congress of Hymenopterists

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7 th <strong>International</strong> <strong>Congress</strong> <strong>of</strong> <strong>Hymenopterists</strong><br />

20-26 June 2010, Kszeg Hungary<br />

_____________________________________________________________________________________________________<br />

Countless molecular data <strong>of</strong> Hymenoptera species have been gathered over the last years,<br />

constantly growing in size and number. Our knowledge on Hymenoptera phylogeny is<br />

currently limited by the ability to combine these data in a fast, yet accurate and objective way.<br />

We present a novel approach to overcome this problem and to exploit what was published<br />

before and hence picture what we virtually already know. We used all molecular data <strong>of</strong><br />

Hymenoptera taxa accessible through GenBank and put them in a single analysis. Our study<br />

combines approaches to several issues on different levels:<br />

Firstly, we provide a methodical pipeline on how to acquire and prepare those enormous and<br />

variable data for the final tree reconstruction, including automatic download, orthologue<br />

search, sequence processing, quality management, alignment, partitioning, filtering<br />

ambiguous or randomly similar sites and eliminating heterogeneity.<br />

Secondly, we present the methods <strong>of</strong> tree reconstruction that can be performed with very large<br />

datasets in a reasonable time and with high accuracy. Our method <strong>of</strong> choice is tree<br />

reconstruction with a super distance matrix (SDM). The super distance matrix is obtained by<br />

combining NJtrees <strong>of</strong> single genes with optimized branch lengths. Subsequently, the<br />

phylogenetic tree is reconstructed from the matrix with a neighbour-joining algorithm. The<br />

SDM method also provides a super variance matrix that allows identification and elimination<br />

<strong>of</strong> unplaceable taxa.<br />

Thirdly, we show our results on Hymenoptera phylogeny. Open questions include systematic<br />

status and positioning <strong>of</strong> recognized superfamilies and <strong>of</strong> higher taxa, such as Aculeata,<br />

Proctotrupomorpha, and Evaniomorpha. Additionally to our contribution to understanding the<br />

origin and evolution <strong>of</strong> Hymenoptera these results allow us to point out open questions or<br />

weakly supported nodes to guide future studies in terms <strong>of</strong> taxon and marker selection.<br />

Our dataset comprises more than 300 nuclear and mitochondrial genes and some 2000<br />

Hymenoptera species from more than 70 families from all 22 superfamilies currently<br />

recognized.<br />

The Hymenoptera are exceptionally numerous and diverse in terms <strong>of</strong> life history and feeding<br />

habits, i.e. include parasitoids, predators, phytophaga, eusocial and solitary taxa, and are<br />

known to be systematically challenging. This makes them an excellent exemplar clade for our<br />

approach. However, the presented approach is designed as a general approach and can be<br />

applied to all taxa following the presented pipelines <strong>of</strong> data preparation and analysis.<br />

____________________________________<br />

The poverty <strong>of</strong> partitioned analyses and character-type chauvinism<br />

Kurt M. Pickett 1 * & James M. Carpenter 2<br />

1 Department <strong>of</strong> Biology, University <strong>of</strong> Vermont, 120A Marsh Life Science Building, 109 Carrigan Drive,<br />

Burlington, VT 05405, USA; kurt.pickett@uvm.edu<br />

2 American Museum <strong>of</strong> Natural History, NYC, USA; carpente@amnh.org<br />

Phylogenetic analyses <strong>of</strong> individual partitions <strong>of</strong> data (gene fragments, parts <strong>of</strong> the<br />

morphology, behavior, etc). sometimes give different results. This should be <strong>of</strong> no surprise,<br />

as even small amounts <strong>of</strong> data from the same partition will do the same. However, the<br />

common interpretation that is given is that morphology and molecules show fundamentally<br />

different patterns, leading researchers to simply pick the phylogeny from whichever data<br />

source they prefer, or to malign the utility <strong>of</strong> another data source entirely. Using social wasps<br />

and their close relatives as examples, we show that multiple different analyses that combine<br />

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