Dev Genes Evol (2008) 218:141–152 Hampton of the Kansas Agricultural Experiment Station Scanning Electron Microscope Laboratory in the Department of Entomology at Kansas State University for expert assistance with SEMs. This work was supported by grants from the National Science Foundation (IOB0321882) (RED, SJB and TDS), the National Institutes of Health (HD29594) (SJB, RED and TDS), the Japanese Society for the Promotion of Science (YT), and the Terry C. Johnson Center for Basic Cancer Research at Kansas State University. Open Access This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which per- mits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. References Bhojwani J, Shashidhara LS, Sinha P (1997) Requirement of teashirt (tsh) function during cell fate specification in developing head structures in Drosophila. Dev Genes Evol 207:137–146 Brown SJ, Hilgenfeld RB, Denell RE (1994a) The beetle Tribolium castaneum has a fushi tarazu homolog expressed in stripes during segmentation. Proc Natl Acad Sci USA 91:12922–12926 Brown SJ, Patel NH, Denell RE (1994b) Embryonic expression of the single Tribolium engrailed homolog. Dev Genet 15:7–18 Brown SJ, Mahaffey JP, Lorenzen MD, Denell RE, Mahaffey JW (1999) Using RNAi to investigate orthologous homeotic gene function during development of distantly related insects. Evol Dev 1:11–15 Brown S, Fellers J, Shippy T, Denell R, Stauber M, Schmidt-Ott U (2001) A strategy for mapping bicoid on the phylogenetic tree. Curr Biol 11:R43–R44 Brown SJ, Shippy TD, Beeman RW, Denell RE (2002) Tribolium Hox genes repress antennal development in the gnathos and trunk. Mol Phylogenet Evol 24:384–387 Caubit X, Core N, Boned A, Kerridge S, Djabali M, Fasano L (2000) Vertebrate orthologues of the Drosophila region-specific pattern- ing gene teashirt. Mech Dev 91:445–448 Curtis CD, Brisson JA, DeCamillis MA, Shippy TD, Brown SJ, Denell RE (2001) Molecular characterization of Cephalothorax, the Tribolium ortholog of Sex combs reduced. Genesis 30:12–20 de Zulueta P, Alexandre E, Jacq B, Kerridge S (1994) Homeotic complex and teashirt genes co-operate to establish trunk segmental identities in Drosophila. Development 120:2287–2296 Drosophila 12 Genomes Consortium (2007) Evolution of genes and genomes on the Drosophila phylogeny. Nature 450:203–218 El-Kifl AH (1953) Morphology of the adult Tribolium confusum Duv. and its differentiation from Tribolium (Stene) castaneum Herbst. Bull Soc Fouad 1er Entomol 37:173–249 Erkner A, Gallet A, Angelats C, Fasano L, Kerridge S (1999) The role of Teashirt in proximal leg development in Drosophila: ectopic Teashirt expression reveals different cell behaviours in ventral and dorsal domains. Dev Biol 215:221–232 Fasano L, Roder L, Core N, Alexandre E, Vola C, Jacq B, Kerridge S (1991) The gene teashirt is required for the development of Drosophila embryonic trunk segments and encodes a protein with widely spaced zinc finger motifs. Cell 64:63–79 Force A, Lynch M, Pickett FB, Amores A, Yan Y-L, Postlethwait J (1999) Preservation of duplicate genes by complementary, degenerative mutations. Genetics 151:1531–1545 Gonzalez-Crespo S, Morata G (1996) Genetic evidence for the subdivision of the arthropod limb into coxopodite and telopodite. Development 122:3921–3928 151 Herke SW, Serio NV, Rogers BT (2005) Functional analyses of tiptop and antennapedia in the embryonic development of Oncopeltus fasciatus suggests an evolutionary pathway from ground state to insect legs. Development 132:27–34 Holt RA, Subramanian GM, Halpern A, Sutton GG, Charlab R et al (2002) The genome sequence of the malaria mosquito Anopheles gambiae. Science 298:129–149 Honeybee Genome Sequence Consortium (2006) Insights into social insects from the genome of the honeybee Apis mellifera. Nature 443:931–949 Kennerdell JR, Carthew RW (2000) Heritable gene silencing in Drosophila using double-stranded RNA. Nat Biotechnol 18:896– 898 Kumar S, Tamura K, Nei M (2004) MEGA3: integrated software for molecular evolutionary genetics analysis and sequence align- ment. Brief Bioinform 5:150–163 Laugier E, Yang Z, Fasano L, Kerridge S, Vola C (2005) A critical role of teashirt for patterning the ventral epidermis is masked by ectopic expression of tiptop, a paralog of teashirt in Drosophila. Dev Biol 283:446–458 Mace KA, Pearson JC, McGinnis W (2005) An epidermal barrier wound repair pathway in Drosophila is mediated by grainy head. Science 308:381–385 Manfroid I, Caubit X, Kerridge S, Fasano L (2004) Three putative murine Teashirt orthologues specify trunk structures in Drosoph- ila in the same way as the Drosophila teashirt gene. Development 131:1065–1073 Martindale MQ (2005) The evolution of metazoan axial properties. Nat Rev Genet 6:917–927 Nie W, Stronach B, Panganiban G, Shippy T, Brown S, Denell R (2001) Molecular characterization of Tclabial and the 3′ end of the Tribolium homeotic complex. Dev Genes Evol 211:244–251 Ochman H, Gerber AS, Hartl DL (1988) Genetic applications of an inverse polymerase chain reaction. Genetics 120:621–623 Patel NH, Kornberg TB, Goodman CS (1989) Expression of engrailed during segmentation in grasshopper and crayfish. Development 107:201–212 Patel NH, Condron BG, Zinn K (1994) Pair-rule expression patterns of even-skipped are found in both short- and long-germ beetles. Nature 367:429–434 Patel M, Farzana L, Robertson LK, Hutchinson J, Grubbs N, Shepherd MN, Mahaffey JW (2007) The appendage role of insect disco genes and possible implications on the evolution of the maggot larval form. Dev Biol 309:56–69 Peterson MD, Rogers BT, Popadic A, Kaufman TC (1999) The embryonic expression pattern of labial, posterior homeotic complex genes and the teashirt homologue in an apterygote insect. Dev Genes Evol 209:77–90 Prpic NM, Wigand B, Damen WG, Klingler M (2001) Expression of dachshund in wild-type and distal-less mutant Tribolium corrob- orates serial homologies in insect appendages. Dev Genes Evol 211:467–477 Putnam NH, Srivastava M, Hellsten U, Dirks B, Chapman J, Salamov A, Terry A, Shapiro H, Lindquist E, Kapitonov VV, Jurka J, Genikhovich G, Grigoriev IV, Lucas SM, Steele RE, Finnerty JR, Technau U, Martindale MQ, Rokhsar DS (2007) Sea anemone genome reveals ancestral eumetazoan gene repertoire and genomic organization. Science 317:86–94 Richards S, Liu Y, Bettencourt BR, Hradecky P, Letovsky S, Nielsen R, Thornton K, Hubisz MJ, Chen R, Meisel RP, Couronne O, Hua S, Smith MA, Zhang P, Liu J, Bussemaker HJ, van Batenburg MF, Howells SL, Scherer SE, Sodergren E, Matthews BB, Crosby MA, Schroeder AJ, Ortiz-Barrientos D, Rives CM, Metzker ML, Muzny DM, Scott G, Steffen D, Wheeler DA, Worley KC, Havlak P, Durbin KJ, Egan A, Gill R, Hume J, Morgan MB, Miner G, Hamilton C, Huang Y, Waldron L,