Source: RUTGERS, THE STATE UNIVERSITY OF NEW JERSEY submitted to NRP
THE PHYLOGENY OF ODONATA (DRAGONFLIES AND DAMSELFLIES) AND THE EVOLUTION OF WINGS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
0205951
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2005
Project End Date
Sep 30, 2011
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
RUTGERS, THE STATE UNIVERSITY OF NEW JERSEY
3 RUTGERS PLZA
NEW BRUNSWICK,NJ 08901-8559
Performing Department
Ecology, Evolution & Natural Resources
Non Technical Summary
There is currently no consensus about how dragonfly and damselfly families are related to one another. Like dinosaurs and birds, dragonflies and their evolution has broad reaching impacts on science. This phylogeny will provide a framework for discussing these organisms with the public, as well as give us an example of what the first animal on earth to fly might have looked like. Also, as integral components of freshwater ecosystems, Odonata are also important as indicators of water quality. This project will establish the phylogenetic relationships among odonates. The purpose of the study is to stabilize the classification of Odonata.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
11202101130100%
Goals / Objectives
The primary objective of this research is to investigate the higher level relationships among Odonata using DNA sequence data and morphology. We will address the following questions: 1. What is the phylogenetic position of Odonata within basal Pterygota (winged insects)? 2. What are the phylogenetic relationships among odonate families? 3. What morphological, ecological, and behavioral innovations are correlated with diversity? These Objectives lead to many "spinoff" benefits. The branching nature of phylogenetic analyses means that side projects can be designed for student education at virtually any level, from part-time undergraduate research experience (for example, exploring the population structure of a particular genus of Dragonfly in New Jersey), to full blown thesis research for graduate students (for example, the phylogeny of Gomphidae: a diverse cosmopolitan family of dragonflies).
Project Methods
We have representatives of all odonate families, and all but four subfamies in our possession. For the placement of Odonata within Pterygota (objective 1), we will include representatives of Protura, Collembola, Diplura, Archaeognatha, Thysanura, Ephemeroptera, Plecoptera, Orthoptera and Blattodea. In addition, we will sequence 5 divergent ephemeropterans. Heavy sampling of Ephemeroptera along with opportunistic sampling of other insect orders from GenBank will provide appropriate outgroups. Comprehensive morphological data has been published for each of the suborders (Carle 1986, 1995, 1996; Bechly 1994, Carle and Kjer 2002, Rehn 2003). We propose to combine morphological datasets into an analysis of Odonata + outgroups, utilizing characters from living and fossil material, different life stages and both sexes. For all of our taxa, we propose to sequence the entire nuclear large subunit gene (28S), 1400 nts, of EF-1alpha (most of the gene, including about 300 nts of intron sequence). These data will be added to complete 12S and 16S sequences already in GenBank. Phylogenetic analysis will be performed via equally and differentially weighted parsimony, and maximum likelihood using PAUP* (Swofford, 1999), and MrBayes (Heulsenbeck and Renquist, 2001). Branch support will be analyzed by nonparametric bootstrapping (Felsenstein 1985), and by jackkniffing, according to the recommendations of (Farris et al. 1996). Support under likelihood will be reported as Bayesian posterior probabilities (Heulsenbeck and Ronquist 2001). Morphological methods - We will perform separate morphological and combined analyses as we continue to update and evaluate our morphological results. Carles data matrices (Carle 1995, 1996, Carle and Kjer 2002), combined with Rehns (2003) would include the most complete morphological data sets compiled to date for Odonata. The array of characters utilized encompasses different life stages, both sexes, external and internal morphology, and several newly discovered characters; these data will be re-evaluated and updated.

Progress 10/01/05 to 09/30/11

Outputs
OUTPUTS: Approximately 5000 nucleotides were seqeunced from each of 200 species of Odonata. Approximately 200 species of Odonata were collected from a 6 week field expedition to Australia. Multiple international conferences were attended, including Systematic Biology, 2005, 2006, 2007, 2009, 2010, and 2011, and the Dresden meetings on Insect Phylogeny, 2005, 2007, and 2011. PARTICIPANTS: Frank Carle, Ph.D. has collected much of the sequence data. Dr. Carle also teaches 2 courses per semester at Rutgers. Jessica Ware, Ph.D. was trained on this project. She has obtained a tenure track position at Rutgers, Newark. Jessica has authored multiple papers on Odonata. Xin Zhou, Ph.D. was trained during this project. Xin is currently employed as a vice president at Beijing Genomics Institute. Xin developed an enhanced method of molecular taxonomy. Jessica Thomas was employed as a postdoctoral associate during this project. She is currently working on another postdoc in England. Jessica Thomas, with Jessica Ware, organized an international symposium on molecular dating analysis at Rutgers. TARGET AUDIENCES: Other scientists: We have presented our research both in peer reviewed journals, book chapters, and at talks and posters at international meetings. General public: We have discovered that one of the most interesting damselflies, the "helicopters", which pick spiders off their webs in Central America, are actually very closely related to the little blue coenagrionid damselflies so common here in North America. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Two graduate students were trained; Jessica Ware, currently employed as an assistant professor at Rutgers, Newark, and Xin Zhou, currently employed as a vice president at Beijing Genomics Institute. It was discovered that Hemiphlebia is an insect of special conservation interest because of its key phylogenetic position. It was discovered that the large family, Coenagrionidae, is polyphyletic, and in need of taxonomic revision. The family, Pseudostigmatidae, (which includes the worlds largest damselflies) is nested within the Coenagrionidae. We confirmed the utility of manual alignment methods for rRNA nucleotide data. We developed a protocol for molecular taxonomy that includes an additional gene to the COI "barcode" fragment, as well as morphological considerations for species identification.

Publications

  • Trautwein, M.D., Wiegman, B.M., Beutel, R., Kjer, K.M. and Yeates, D.K. 2012. Advances in Insect Phylogeny at the Dawn of the Postgenomic Era. Annu. Rev. Entomol. 57:449-68
  • Flint, O.S., and Kjer, K.M. 2011. A new species of Neophylax from Northern Virginia, USA (Trichoptera: Uenoidae). Proc. Entomol. Soc. Wash. 113:7-13
  • Geraci CJ, Zhou X, Morse JC, and Kjer K.M. 2010. Defining the genus Hydropsyche (Trichoptera:Hydropsychidae) based on DNA and morphological evidence. J. N. Amer. Benthological Soc. 29: 918-933


Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: On January 8, my postdoc, Jessica Thomas, and my former graduate student, Jessica Ware, organized and hosted a large symposium at Rutgers entitled "North Eastern Symposium on Evolutionary Divergence Times" In the spring, I was invited to give two presentations at the University of Connecticut: 1. Kjer, K.M. 2010. DNA Barcoding: Boon or Boondoggle University of Connecticut regular seminar series. 2. Kjer, K.M. 2010. The phylogeny of Insecta. University of Connecticut special topic seminar. While in Connecticut, I also presented a special teaching seminar for Dr. Chris Simon's Phylogenetics course. In June, I hosted a visiting scholar, Sylvester Ogbogu, from Nigeria. Dr. Ogbogu spent time at Rutgers discussing potential collaborations, and then went to the University of Minnesota, to work with my collaborator, Ralph Holzenthal. I attended the National annual meeting of the Society of Systematic Biologists in Portland in June. I serve on their editorial staff as an Associate Editor, and also, on their council. I brought my new graduate student, Paul Frandsen to these meetings. Afterwards, Paul and I conducted field work in the Pacific NorthWest. PARTICIPANTS: Elizabeth Scott, postdoctoral scholar, collected data Jessica Thomas, postdoctoral scholar, collected data Sylvester Ogbogu, visiting scholar, discussed collaborations TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Discoveries from previous publications have been verified by others. We are still collecting data for our Odonata project, so the scientific impacts from our specific project are yet to be accomplished for 2010. However, my former postdoc, Elizabeth Scott, coauthored a successful NSF grant with me in Systematic Biology (DEB 1021299) for over $500,000, and this should count as a significant outcome in mentoring women in science. Similarly, my former graduate student, Jessica Ware, took a tenure track at Rutgers, Newark.

Publications

  • Geraci C.J., Zhou X., Morse J.C., and Kjer K.M. 2010. Defining the genus Hydropsyche (Trichoptera: Hydropsychidae) based on DNA and morphological evidence. J. N. Amer. Benthological Soc. 29: 918-933.
  • The Tree of Life web project: Trichoptera, Caddisflies. http://tolweb.org/Trichoptera approximately 50 pages contributed. Ralph W. Holzenthal, Roger J. Blahnik, Aysha Prather, and Karl Kjer. 2010. Permanently archived.


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: We presented our findings at a large number of conferences. I spoke at one invited conference "Kjer, K.M., and Zhou, X. Linking barcodes with phylogenetics; a fruitfull collaboration. Taller del Nodo IBUNAM de la Red MEXBOL El Codigo de Barras de la Vida. Mexico City, Mexico, March 2009" I gave 4 invited talks: " Homology in terms of position and connection: The morphology of rRNA and its influence on Insect Phylogeny" at the University of Bonn, Germany; "Insect phylogeny and structural alignments." at the Natural history museum in Jena Germany, "The phylogeny of Odonata: Wings lie" at the Department of Biology in Hannover University, and "Homology in terms of position and connection: The morphology of rRNA and its influence on Insect Phylogeny" at the University of Minnesota Department of Entomology. We presented our work at the Society of Systematic Biology in 2008: Kjer, K.M., Letch, H, and Misof, B." Can we replace manual alignments for rRNAs: an assessment of two new programs" PARTICIPANTS: Mike May, Professor of Entomology worked on Odonata phylogeny. Frank Carle, PhD. worked on collecting and analyzing data, and teaching at Rutgers. Katelyn Hughes, an undergraduate at Rutgers, worked in my lab and learned about laboratory techniques and scientific methods. TARGET AUDIENCES: All evolutionary biologists are interested in rRNA alignment issues. Odonatologists are interested in how these insects are related. The general public has in interest in dragonflies. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Our phylogeny of Odonata provides a new and more strongly supported hypothesis of relationships within this ancient taxon. Partial results have been published or accepted in two papers; major findings are listed above. Manual alignment of rRNA data significantly increases congruence of conclusions from 18S data to conclusions from morphology. Three papers that discussed alignment and three that discussed weighting and models were produced while we were supported by this grant. These finding show that: 1. Structure is an important consideration in rRNA alignments 2. Parameter selection with computer alignments can be arbitrary 3. rRNA structure influences estimated divergence dates 4. The most commonly used weighting schemes (transversions and codon weights) perform poorly 5. A site specific model was proposed for mitochondrial genome data. We also discussed the difficulties of estimating phylogenies when radiations are ancient and rapid. These papers found that; 1. the relationships among orthopteroid orders are currently unresolved, and will be extremely difficult to resolve by any means 2. the relationships among the 'palaeopterans' is currently unresolved, despite several papers strongly supporting mutually exclusive results. Contributions to Education and Human Resources:Jessica Ware received her PhD, and has been working on a prestigious postdoc at the American Musuem. She just received and accepted a tenure track position at Rutgers University-Newark. Jessica is among the first African American women to work in such a position in evolutionary biology. Ware has 6 published manuscripts, and has submitted two others. Many more are in preparation. Ware has already been invited to present two talks at international meetings, and has presented at 13 others. Three of these presentations were recognized with awards. She is well connected with the odonatological community. She has recieved the Bevier fellowship which supported her final year at Rutgers (Rutgers' highest graduate student award), and has been a Cook Excellence Fellow. We have trained 4 undergraduate students under this award (and the REU supplement associated with it) Contributions to Resources for Science and Technology: We collected approximately 1500 Odonata from Australia. All of these specimens have been placed in museum collections, many returned to museums in Australia. Contributions Beyond Science and Engineering: Our phylogenetic placement of the Australian Hemiplebia confirms it as a taxon of conservation interest.

Publications

  • Lopez-Vaamonde, C., Wikstrom N., Kjer K.M., Weiblen G.D., Rasplus, J.Y., Machado C., and Cook J.M. 2009. Molecular dating and biogeography of fig-pollinating wasps. Molecular Phylogenetics and Evolution. 52:715-26.
  • Johanson, K-A., Kjer, K.M., and Malm, T. 2009. Testing the monophyly of the New Zealand and Australian endemic family Conoesucidae Ross based on combined molecular and morphological data (Insecta: Trichoptera: Sericostomatoidea). Zoologica Scripta 38: 563 - 573
  • Marvaldi, A,E., Duckett, C.N. Kjer, K.M., and Gillespie, J.J. 2009. Structural alignment of 18S and 28S rDNA sequences provides insights into phylogeny of Phytophaga (Coleoptera: Curculionoidea and Chrysomeloidea). Zoologica Scripta 38: 63-77.


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Graduate student, Jessica Ware, completed her PhD in June, 2008 on Odonata. PARTICIPANTS: Jessica Ware graduated with her PhD, and went on to postdoctoral positions at the American Museum of Natural History, and the Smithsonian Institution. George Baskinger, an undergraduate, published his work on Celithemis. Frank Carle supervised much of the work. Mike May contributed his expertise on Odonata as a consultant, and coauthor. TARGET AUDIENCES: Dragonflies are among the most popular groups for amateur interest (along with birds and butterflies). The phylogeny we reported changes the classification of the group. Pseudostigmatidae is among the most charismatic of insects, and our work places this family in an evolutionary context. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Coenagrionidae, those common little blue damselflies, was found to be paraphyletic, with the giant helicopter damselflies (Pseudostigmatidae) evolving from within Coenagrionidae. This shows the plasticity of size among the Odonata, and has fundamentally altered the taxonomy of the group.

Publications

  • Kjer, K. M., Roshan, U. and Gillepie, J.G. 2008. Structural and Evolutionary Considerations For Multiple Sequence alignment of RNA, and the challenges for Algorithms that ignore them. in Perspectives on Biological Sequence Alignment: Where, How, and Why It Matters". University of California Press.
  • Baskinger G.M, Ware J.L., Kornell D.D. May, M.L, and Kjer, K.M. 2008. A phylogeny of Celithemis inferred from mitochondrial and nuclear DNA sequence data and morphology (Anisoptera: Libellulidae). Odonatologica 37: 101-109


Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: We presented our preliminary results at the Systematic Biology meetings in Fairbanks in June, 2004; the 4th World Dragonfly Association (WDA) symposium of Odonatology meetings in Spain, in July 2004; the Annual meeting of the North American Benthological Society in Anchorage, AK, in June 2006; the American Entomological Society, February, 2007, the 5th WDA Symposium of Odonatology, Swakopmund, Namibia, April 2007; the Annual Meeting of the Dragonfly Society of the Americas, AZ, July 2007. And at the national Entomological Society meetings in 2006, and the Systematic Biology meetings in 2006. Kjer presented findings at the 3rd Dresden meetings on Insect Phylogeny in 2007. We collected approximately 1500 Odonata from Australia. All of these specimens have been placed in museum collections, many returned to museums in Australia. We have nearly completed training our graduate student, Jessica Ware in Phylogentic systematics and both molecular and morphological data collection. We have taken her to Australia to train her in field work. Ware has 6 published manuscripts, and has submitted two others. Seven more are in preparation. Ware has already been invited to present two talks at international meetings, and has presented at 13 others. Three of these presentations were recognized with awards. She is well connected with the odonatological community. She has recieved the Bevier fellowship to support her final year at Rutgers (Rutgers' highest graduate student award), and has been a Cook Excellence Fellow. We have trained 4 undergraduate students under this project, with additional support from an NSF REU supplement. Ware, as an African American woman, has been an excellent spokesperson for advancing women of color in science. She has done the following: -Insect presentation, Yellow Brick Road Preschool, Highland Park, NJ: August 2007 -Library Talk in Old Bridge, NJ: June 2006 - Insect presentation to the New Brunswick, NJ, Boy scouts troop: April 2006 -Taught a 5-day "Introduction to Entomology Bug Club" to nine children aged 6-12 at Kean University, NJ: Summer 2005. -Spoke to 25 women from the Douglass Project, Rutgers University: Summer 2005 and Summer 2006. - Library talks at the New Brunswick Public Library: February, 2005 PARTICIPANTS: Mary McGlauglin, Rutgers undergraduate George Baskinger, Rutgers undergraduate

Impacts
Our work has fundamentally changed the phylogeny, and thus classification of the entire order, Odonata. Specific findings, both in terms of phylogeny, and the behavioral implications of this phylogeny are as follows: Zygoptera is monophyletic, with superfamilies matching conclusions of Bechly. Hemiphlebia is a basal lestoid. Philoganga is a Diphlebiid, counter to Rehn, 2003. Anisoptera is monophyletic, with superfamilies as in Carle and Kjer (2002). Placement of Neopetalia in Libelluloidea and establishment of Austropetaliidae as basal aeschnoids is supported by morphologic and molecular data. Synthemistids, gomphomacromiids, and their relatives form a monophyletic group. Macromiids, corduliids s.s. (i.e., Corduliinae of Davies and Tobin 1985), and libellulids are each monophyletic. Similarities between petalurid and cordulagastrid secondary genitalia, proventriculus, and larval labium are due to synapomorphy. Similarities between gomphid and libellulid oviposition and secondary genitalia are due to convergent loss. Similarities between aeshnid and libellulid epiproct, eye separation, planate veins, anal loop, and abdominal carina are due to convergence. Petiolate wings are plesiomorphic for extant Odonata. Mate recognition signals in wings, legs, and abdomen are convergent [This is not news - nobody thought that calopterygids and libellulids are sister taxa]. Tandem oviposition is convergent in both suborders. In Anisoptera shifts from small streams to larger, slower water have occurred repeatedly. Our phylogenetic placement of the Australian Hemiplebia confirms it as a taxon of conservation interest. Our phylogeny of Odonata provides a new and more strongly supported hypothesis of relationships within this ancient taxon. Partial results have been published or accepted in two papers; major findings are listed above. Manual alignment of rRNA data significantly increases congruence of conclusions from 18S data to conclusions from morphology. Three papers that discussed alignment and three that discussed weighting and models were produced while we were supported by this project. These finding show that: 1. Structure is an important consideration in rRNA alignments 2. Parameter selection with computer alignments can be arbitrary 3. rRNA structure influences estimated divergence dates 4. The most commonly used weighting schemes (transversions and codon weights) perform poorly 5. A site specific model was proposed for mitochondrial genome data. We also discussed the difficulties of estimating phylogenies when radiations are ancient and rapid. These papers found that; 1. the relationships among orthopteroid orders are currently unresolved, and will be extremely difficult to resolve by any means 2. the relationships among the 'palaeopterans' is currently unresolved, despite several papers strongly supporting mutually exclusive results.

Publications

  • May, M.L., and J. H. Matthews. 2008. Migration in odonata: An overview with special focus on Anax junius. In Dragonflies, Model Organisms for Ecological and Evolutionary Research. Cordoba-Aguilar A., Ed., Oxford University Press.
  • May, M. L., and S. W. Dunkle. 2007. Damselflies of North America, Color Supplement. Scientific Publishers, Gainesville, FL. 156.
  • Stoks, R. , J. L. Nystrom , M. L. May and M. A. McPeek. 2005. Parallel evolution in ecological and reproductive traits to produce cryptic damselfly species across the holarctic. Evolution 59:1976-1988.
  • Ware, J. L., M. L. May, K.M. Kjer 2007. Phylogeny of the higher Libelluloidea (Anisoptera: Odonata): an exploration of the most speciose superfamily of dragonflies, Molecular Phylogenetics and Evolution, vol. 45: 289-310
  • Ware, J. L., Ho, S., Kjer, K. 2007. Divergence dates of libelluloid dragonflies (Odonata: Anisoptera) estimated from rRNA using paired-site substitution models, Molecular Phylogenetics and Evolution, p.
  • Westfall, M. J., and M. L. May. 2006. Damselflies of North America, Revised Edition. Scientific Publishers, Gainesville, FL. 503 pp.
  • Whitfield, J. B and Kjer, K. M. 2008. Ancient Rapid Radiations of Insects: Challenges for Phylogenetic Analysis, Annu. Rev. Entomol., vol. 53, 449-472
  • Wikelski, M., D. Moskowitz, J. S. Adelman, J. Cochran, D. S. Wilcove, and M. L. May. 2006. Simple rules guide dragonfly migration. Biol. Lett. 2:325-329.
  • Zhou, X., Kjer, K.M., and J.C. Morse. 2007. Associating Larvae and Adults of Chinese Hydropsychidae Caddisflies (Insecta: Trichoptera) Using DNA Sequences. J. N. Amer. Benthological Soc. 26:719-742.
  • Holzenthal R.W., Blahnik, R.J., Prather, A.L., and Kjer K.M. 2007. Order Trichoptera Kirby 1813 (Insecta), Caddisflies. In: Zhang, Z.-Q., and Shear, W.A. (Eds). 2007 Linneaus Tercentenary: Progress in Invertebrate Taxonomy. Zootaxa. 58 pp. in press
  • Kjer, K. M., J. J. Gillespie, & K. A. Ober. 2006. Structural homology in ribosomal RNA, and a deliberation on POY", Arthropod Systematics and Phylogeny. 64:71-76
  • Kjer, K.M., Carle, F.L, Litman, J., and Ware, J. 2006. A molecular phylogeny of Hexapoda, Arthropod Systematics and Phylogeny 64:35-44
  • Kjer, K. M., J. J. Gillespie, & K. A. Ober. 2007. Opinions on multiple sequence alignment, and an empirical comparison of repeatability and accuracy between POY and structural alignments, Systematic Biology. 56:133-146
  • Kjer, K. M., Swigonova, Z., LaPolla, J.S., and R.E. Broughton 2007. Why Weight? Molecular Phylogenetics and Evolution, vol. 43:999-1004
  • Kjer, K. M., & R.L Honeycutt 2007. Site Specific Rates of Mitochondrial Genomes and the Phylogeny of Eutheria", BMC-Evolutionary Biology, 7:8 Designated as highly accessed
  • May, M. L., and F. L. Carle. 2005. Pamita hannahdaltonae gen. nov., sp. nov. from Baltic amber (Odonata: Amphipterygidae). Int. J. Odonatology 8:213-221.


Progress 01/01/06 to 12/31/06

Outputs
We have completed most of the data collection for this project, and are currently analyzing the data. We have made several international presentations on our preliminary data, and have been invited to provide a book chapter on the phylogeny and classification of Odonata. We have travelled to Australia, supported by NSF, and to Costa Rica (on personal funds) to obtain specimens we need. We are training a graduate student, Jessica Ware. Ms Ware is making good progress, and is expected to finish her dissertation within a year. She has submitted a paper to Molecular Phylogenetics and Evolution.

Impacts
The phylogeny of Odonata will be proposed and the classification, stabilized. Odonata will be placed in a phylogenetic context, with respect to the other winged insect orders.

Publications

  • Kjer, K. M., J. J. Gillespie, & K. A. Ober. 2007. Opinions on multiple sequence alignment, and an empirical comparison of repeatability and accuracy between POY and structural alignments. Systematic Biology 56:xxx-xxx (in press)
  • LaPolla, J.S., Schultz, T.R., Kjer, K.M., & J.F. Bischoff. 2006. Phylogeneric position of the ant genus Acropaga Roger (Hymenoptera: Formicidae) and the evolution of trophophoresy. Insect Syst. Evol. 37:197-212.
  • Kjer, K. M., J. J. Gillespie, & K. A. Ober. 2006. Structural homology in ribosomal RNA, and a deliberation on POY. Arthropod Systematics and Phylogeny. 64:71-76
  • Kjer, K.M., Carle, F.L, Litman, J., and Ware, J. 2006. A molecular phylogeny of Hexapoda. Arthropod Systematics and Phylogeny. 64:35-44
  • Kjer, K.M. 2004. Aligned 18S and Insect phylogeny. Systematic Biology 53:506-514