The biting edge of the primitive arthropod mandible consists of a biting incisor process and a crushing molar process. These structures are thought to be derived from a structure known as an endite but the pre...
Authors: Joshua F Coulcher and Maximilian J Telford
In most eumetazoans studied so far, Hox genes determine the identity of structures along the main body axis. They are usually linked in genomic clusters and, in the case of the vertebrate embryo, are expressed wi...
Authors: Juan Pascual-Anaya, Noritaka Adachi, Susana Álvarez, Shigeru Kuratani, Salvatore D’Aniello and Jordi Garcia-Fernàndez
Digital anatomical atlases are increasingly used in order to depict different gene expression patterns and neuronal morphologies within a standardized reference template. In evo-devo, a discipline in which the...
Authors: Albina Asadulina, Aurora Panzera, Csaba Verasztó, Christian Liebig and Gáspár Jékely
The Hawaiian endemic genus Clermonti a (Campanulaceae) includes 22 species, 15 of which, the double-corolla species, are characterized by an extra whorl of organs that appear to be true petals occupying what is n...
Authors: Katherine A Hofer, Raili Ruonala and Victor A Albert
The biting mandible of the arthropods is thought to have evolved in the ancestor of the insects, crustaceans and myriapods: the Mandibulata. A unique origin suggests a common set of developmental genes will be...
Authors: Joshua F Coulcher and Maximilian J Telford
The vertebrate pharyngeal apparatus, serving the dual functions of feeding and respiration, has its embryonic origin in a series of bulges found on the lateral surface of the head, the pharyngeal arches. Devel...
Neuronal antibodies that show immunoreactivity across a broad range of species are important tools for comparative neuroanatomy. Nonetheless, the current antibody repertoire for non-model invertebrates is limi...
Activity of the Transforming growth factor-β (TGFβ) pathway is essential to the establishment of body axes and tissue differentiation in bilaterians. Orthologs for core pathway members have been found in all m...
Authors: Gina M Sorrentino, William Q Gillis, Jamina Oomen-Hajagos and Gerald H Thomsen
Animals with a spiral cleavage program, such as mollusks and annelids, make up the majority of the superphylum Lophotrochozoa. The great diversity of larval and adult body plans in this group emerges from this...
Authors: Deirdre C Lyons, Kimberly J Perry, Maryna P Lesoway and Jonathan Q Henry
Variation in fruit morphology is important for plant fitness because it influences dispersal capabilities. Approximately half the members of tribe Brassiceae (Brassicaceae) exhibit fruits with segmentation and...
Authors: Mariano Avino, Elena M Kramer, Kathleen Donohue, Alexander J Hammel and Jocelyn C Hall
The gastrula stage represents the point in development at which the three primary germ layers diverge. At this point the gene regulatory networks that specify the germ layers are established and the genes that...
Authors: Roy Vaughn, Nancy Garnhart, James R Garey, W Kelley Thomas and Brian T Livingston
The timing of the placental mammal radiation has been a source of contention for decades. The fossil record of mammals extends over 200 million years, but no confirmed placental mammal fossils are known prior ...
The mechanisms by which the conserved genetic “toolkit” for development generates phenotypic disparity across metazoans is poorly understood. Echinoderm larvae provide a great resource for understanding how de...
Authors: Brenna S McCauley, Erin P Wright, Cameron Exner, Chisato Kitazawa and Veronica F Hinman
Talpid moles show many specializations in their adult skeleton linked to fossoriality, including enlarged hands when compared to the feet. Heterochrony in developmental mechanisms is hypothesized to account fo...
Authors: Constanze Bickelmann, Christian Mitgutsch, Michael K Richardson, Rafael Jiménez, Merijn AG de Bakker and Marcelo R Sánchez-Villagra
Intercellular signaling via the Notch pathway regulates cell fate, patterning, differentiation and proliferation, and is essential for the proper development of bilaterians and cnidarians. To investigate the o...
Sox genes are HMG-domain containing transcription factors with important roles in developmental processes in animals; many of them appear to have conserved functions among eumetazoans. Demosponges have fewer S...
Authors: Sofia Fortunato, Marcin Adamski, Brith Bergum, Corina Guder, Signe Jordal, Sven Leininger, Christin Zwafink, Hans Tore Rapp and Maja Adamska
Conway Morris and Caron (2012) have recently published an account of virtually all the available information on Pikaia gracilens, a well-known Cambrian fossil and supposed basal chordate, and propose on this basi...
Plant development has a significant postembryonic phase that is guided heavily by interactions between the plant and the outside environment. This interplay is particularly evident in the development, pattern ...
Recent studies have challenged the widespread view that the pattern of embryogenesis found in Caenorhabditis elegans (clade 9) is characteristic of nematodes in general. To understand this still largely unexplore...
Authors: Jens Schulze, Wouter Houthoofd, Jana Uenk, Sandra Vangestel and Einhard Schierenberg
The enigmatic wormlike parasite Buddenbrockia plumatellae has recently been shown to belong to the Myxozoa, which are now supported as a clade within Cnidaria. Most myxozoans are morphologically extremely simplif...
In the polychaete Platynereis, the primordial germ cells (PGCs) emerge from the vasa, piwi, and PL10 expressing mesodermal posterior growth zone (MPGZ) at the end of larval development, suggesting a post-embryoni...
Authors: Nicole Rebscher, Anika Kristin Lidke and Christian Friedrich Ackermann
Annelids and arthropods each possess a segmented body. Whether this similarity represents an evolutionary convergence or inheritance from a common segmented ancestor is the subject of ongoing investigation.
Authors: Elaine C Seaver, Emi Yamaguchi, Gemma S Richards and Néva P Meyer
Flatworm embryology has attracted attention since the early beginnings of comparative evolutionary biology. Considered for a long time the most basal bilaterians, the Platyhelminthes (excluding Acoelomorpha) a...
Authors: José María Martín-Durán and Bernhard Egger
Flower bilateral symmetry (zygomorphy) has evolved multiple times independently across angiosperms and is correlated with increased pollinator specialization and speciation rates. Functional and expression ana...
This paper is a short report on the 2012 Society of Integrative and Comparative Biology Annual Meeting. Charleston, South Carolina, USA. 3-7 January 2012 (abstracts freely available at
Gene duplication and the subsequent divergence in function of the resulting paralogs via subfunctionalization and/or neofunctionalization is hypothesized to have played a major role in the evolution of plant f...
Authors: Ashley R Christensen and Simon T Malcomber
Larval features such as the apical organ, apical ciliary tuft, and ciliated bands often complicate the evaluation of hypotheses regarding the origin of the adult bilaterian nervous system. Understanding how ne...
Authors: Scott Santagata, Carlee Resh, Andreas Hejnol, Mark Q Martindale and Yale J Passamaneck
Nervous systems are thought to be important to the evolutionary success and diversification of metazoans, yet little is known about the origin of simple nervous systems at the base of the animal tree. Recent d...
Authors: David K Simmons, Kevin Pang and Mark Q Martindale
Parasitism is an important life history strategy in many metazoan taxa. This is particularly true of the Phylum Nematoda, in which parasitism has evolved independently at least nine times. The apparent ease wi...
Authors: Susan J Stasiuk, Maxwell J Scott and Warwick N Grant
Cytasters (cytoplasmic asters) are centriole-based nucleation centers of microtubule polymerization that are observable in large numbers in the cortical cytoplasm of the egg and zygote of bilaterian organisms....
Authors: Miguel Salinas-Saavedra and Alexander O Vargas
A report on the meeting Comparative Genomics of Eukaryotic Microorganisms: understanding the complexity of diversity. Sant Feliu de Guíxols, Spain. October 15-20, 2011.
Here we provide the most comprehensive study to date on the cranial ossification sequence in Lipotyphla, the group which includes shrews, moles and hedgehogs. This unique group, which encapsulates diverse ecol...
Authors: Daisuke Koyabu, Hideki Endo, Christian Mitgutsch, Gen Suwa, Kenneth C Catania, Christoph PE Zollikofer, Sen-ichi Oda, Kazuhiko Koyasu, Motokazu Ando and Marcelo R Sánchez-Villagra
RNAs for embryo patterning and for germ cell specification are localized to the vegetal cortex of the oocyte of Xenopus laevis. In oocytes of the direct developing frog Eleutherodactylus coqui, orthologous RNAs f...
Authors: Richard P Elinson, Michelle C Sabo, Cara Fisher, Takeshi Yamaguchi, Hidefumi Orii and Kimberly Nath
Reptiles are largely under-represented in comparative genomics despite the fact that they are substantially more diverse in many respects than mammals. Given the high divergence of reptiles from classical mode...
Authors: Athanasia C Tzika, Raphaël Helaers, Gerrit Schramm and Michel C Milinkovitch
Nematodes can be subdivided into basal Enoplea (clades 1 and 2) and more derived Chromadorea (clades 3 to 12). Embryogenesis of Caenorhabditis elegans (clade 9) has been analyzed in most detail. Their establishme...
As whole genome and transcriptome sequencing gets cheaper and faster, a great number of 'exotic' animal models are emerging, rapidly adding valuable data to the ever-expanding Evo-Devo field. All these new org...
Authors: Mattias Ormestad, Mark Q Martindale and Eric Röttinger
The placenta is essential for supplying nutrients and gases to the developing mammalian young before birth. While all mammals have a functional placenta, only in therian mammals (marsupials and eutherians) doe...
Authors: Brandon R Menzies, Andrew J Pask and Marilyn B Renfree
MicroRNAs are small noncoding RNAs regulating expression of protein coding genes at post-transcriptional level and controlling several biological processes. At present microRNAs have been identified in various...
Authors: Simona Candiani, Luca Moronti, Davide De Pietri Tonelli, Greta Garbarino and Mario Pestarino
A number of innovations underlie the origin of rapid reproductive cycles in angiosperms. A critical early step involved the modification of an ancestrally short and slow-growing pollen tube for faster and long...
Authors: Jason M Abercrombie, Brian C O'Meara, Andrew R Moffatt and Joseph H Williams
Bryozoa is a clade of aquatic protostomes. The bryozoan life cycle typically comprises a larval stage, which metamorphoses into a sessile adult that proliferates by asexual budding to form colonies. The homolo...
Authors: Judith Fuchs, Mark Q Martindale and Andreas Hejnol
The Sox genes are important regulators of animal development belonging to the HMG domain-containing class of transcription factors. Studies in bilaterian models have notably highlighted their pivotal role in cont...
Authors: Muriel Jager, Eric Quéinnec, Hervé Le Guyader and Michaël Manuel
Mammals as a rule have seven cervical vertebrae, except for sloths and manatees. Bateson proposed that the change in the number of cervical vertebrae in sloths is due to homeotic transformations. A recent hypo...
Authors: Irma Varela-Lasheras, Alexander J Bakker, Steven D van der Mije, Johan AJ Metz, Joris van Alphen and Frietson Galis
Stem cells have a critical role during adult growth and regeneration. Germline stem cells are specialized stem cells that produce gametes during sexual reproduction. Capitella teleta (formerly Capitella sp. I) is...
Authors: Vincent C Giani Jr, Emi Yamaguchi, Michael J Boyle and Elaine C Seaver
Hox proteins specify segment identity during embryogenesis and have typical associated expression patterns. Changes in embryonic expression and activity of Hox genes were crucial in the evolution of animal body p...
Authors: Suzanne V Saenko, Marta SP Marialva and Patrícia Beldade
The Pax transcription factor gene eyegone (eyg) participates in many developmental processes in Drosophila, including the Notch signaling activated postembryonic growth of the eye primordium, global development o...
Authors: Nazanin ZarinKamar, Xiaoyun Yang, Riyue Bao, Frank Friedrich, Rolf Beutel and Markus Friedrich
Tremendous progress has been made in the field of evo-devo through comparisons of related genes from diverse taxa. While the vast number of species in nature precludes a complete analysis of the molecular evol...
Eyes in bilaterian metazoans have been described as being composed of either ciliary or rhabdomeric photoreceptors. Phylogenetic distribution, as well as distinct morphologies and characteristic deployment of ...
Authors: Yale J Passamaneck, Nina Furchheim, Andreas Hejnol, Mark Q Martindale and Carsten Lüter
Segmentation is a hallmark of the arthropods; most knowledge about the molecular basis of arthropod segmentation comes from work on the fly Drosophila melanogaster. In this species a hierarchic cascade of segment...
Authors: Ralf Janssen, Graham E Budd, Nikola-Michael Prpic and Wim GM Damen
Flowering is a critical transition in plant development, the timing of which can have considerable fitness consequences. Until recently, research into the genetic control of flowering time and its associated d...
Authors: Evangeline S Ballerini and Elena M Kramer
Nuclear receptors (NRs) are an ancient superfamily of metazoan transcription factors that play critical roles in regulation of reproduction, development, and energetic homeostasis. Although the evolutionary re...
Authors: Adam M Reitzel, Kevin Pang, Joseph F Ryan, James C Mullikin, Mark Q Martindale, Andreas D Baxevanis and Ann M Tarrant
