The Onychophora are a probable sister group to Arthropoda, one of the most intensively studied animal phyla from a developmental perspective. Pioneering work on the fruit fly Drosophila melanogaster and subsequen...
Authors: Mattias Hogvall, Anna Schönauer, Graham E Budd, Alistair P McGregor, Nico Posnien and Ralf Janssen
For animal cells, ciliation and mitosis appear to be mutually exclusive. While uniciliated cells can resorb their cilium to undergo mitosis, multiciliated cells apparently can never divide again. Nevertheless,...
Authors: April M Bird, George von Dassow and Svetlana A Maslakova
Crustaceans of the genus Daphnia are one of the oldest model organisms in ecotoxicology, ecology and evolutionary biology. The publication of the Daphnia pulex genome has facilitated the development of genetic to...
Authors: Beate Mittmann, Petra Ungerer, Marleen Klann, Angelika Stollewerk and Carsten Wolff
A key early step in embryogenesis is the establishment of the major body axes; the dorsal-ventral (DV) and anterior-posterior (AP) axes. Determination of these axes in some insects requires the function of dif...
Authors: Megan J Wilson, Nathan J Kenny and Peter K Dearden
It is believed that in tapeworms a separate population of undifferentiated cells, the germinative cells, is the only source of cell proliferation throughout the life cycle (similar to the neoblasts of free liv...
Authors: Uriel Koziol, Theresa Rauschendorfer, Luis Zanon Rodríguez, Georg Krohne and Klaus Brehm
Polyclad flatworms offer an excellent system with which to explore the evolution of larval structures and the ecological and developmental mechanisms driving flatworm and marine invertebrate life history evolu...
Heterochronic shifts during ontogeny can result in adaptively important innovations and might be initiated by simple developmental switches. Understanding the nature of these developmental events can provide i...
Authors: Helen M Gunter, Claudia Koppermann and Axel Meyer
Haemocyanin is the respiratory protein of most of the Mollusca. In cephalopods and gastropods at least two distinct isoforms are differentially expressed. However, their physiological purpose is unknown. For t...
Authors: Anne Thonig, Michael Oellermann, Bernhard Lieb and Felix Christopher Mark
While the ecological factors that drive phenotypic radiations are often well understood, less is known about the generative mechanisms that cause the emergence and subsequent diversification of novel features. He...
Authors: Arnaud Martin, Kyle J McCulloch, Nipam H Patel, Adriana D Briscoe, Lawrence E Gilbert and Robert D Reed
Adaptation to a new environment can be facilitated by co-inheritance of a suite of phenotypes that are all advantageous in the new habitat. Although experimental evidence demonstrates that multiple phenotypes ...
Authors: Margaret G Mills, Anna K Greenwood and Catherine L Peichel
An important question in experimental embryology is to understand how the developmental potential responsible for the generation of distinct cell types is spatially segregated over developmental time. Classica...
Authors: Antje HL Fischer, Kevin Pang, Jonathan Q Henry and Mark Q Martindale
The monophyly of Mandibulata - the division of arthropods uniting pancrustaceans and myriapods - is consistent with several morphological characters, such as the presence of sensory appendages called antennae ...
Authors: Prashant P Sharma, Tripti Gupta, Evelyn E Schwager, Ward C Wheeler and Cassandra G Extavour
In Drosophila and many other insects, the Hox genes Ultrabithorax (Ubx) and abdominal-A (abd-A) suppress limb formation on most or all segments of the abdomen. However, a number of basal hexapod lineages retain m...
Comparative studies of developmental processes are one of the main approaches to evolutionary developmental biology (evo-devo). Over recent years, there has been a shift of focus from the comparative study of ...
Authors: Hilde Janssens, Ken Siggens, Damjan Cicin-Sain, Eva Jiménez-Guri, Marco Musy, Michael Akam and Johannes Jaeger
Animals have been described as segmented for more than 2,000 years, yet a precise definition of segmentation remains elusive. Here we give the history of the definition of segmentation, followed by a discussio...
Specification of the germ line is an essential event during the embryonic development of sexually reproducing animals, as germ line cells are uniquely capable of giving rise to the next generation. Animal germ...
In sea urchin larvae the circumesophageal fibers form a prominent muscle system of mesodermal origin. Although the morphology and later development of this muscle system has been well-described, little is know...
Authors: Carmen Andrikou, Edmondo Iovene, Francesca Rizzo, Paola Oliveri and Maria Ina Arnone
Studies on early neurogenesis have had considerable impact on the discussion of the phylogenetic relationships of arthropods, having revealed striking similarities and differences between the major lineages. I...
Authors: Georg Brenneis, Angelika Stollewerk and Gerhard Scholtz
In many bilaterians, asymmetric activation of canonical Wnt (cWnt) signaling at the posterior pole is critical for anterior-posterior (AP) body axis formation. In 16-cell stage sea urchins, nuclearization of β...
Authors: Christine A Byrum and Athula H Wikramanayake
In many insect taxa, wing polymorphism is known to be a consequence of tradeoffs between flight and other life-history traits. The pea aphid Acyrthosiphon pisum exhibits various morphs with or without wings assoc...
Polyclad flatworms are an early branching clade within the rhabditophoran Platyhelminthes. They provide an interesting system with which to explore the evolution of development within Platyhelminthes and among...
Authors: François Lapraz, Kate A Rawlinson, Johannes Girstmair, Bartłomiej Tomiczek, Jürgen Berger, Gáspár Jékely, Maximilian J Telford and Bernhard Egger
The question of whether the ancestral bilaterian had a central nervous system (CNS) or a diffuse ectodermal nervous system has been hotly debated. Considerable evidence supports the theory that a CNS evolved j...
Authors: Linda Z Holland, João E Carvalho, Hector Escriva, Vincent Laudet, Michael Schubert, Sebastian M Shimeld and Jr-Kai Yu
The Mexican tetra (Astyanax mexicanus) has emerged as a good animal model to study the constructive and regressive changes associated with living in cave environments, as both the ancestral sighted morph and the ...
Authors: Atukorallaya Devi Sewvandini Atukorala, Christine Hammer, Megan Dufton and Tamara Anne Franz-Odendaal
Animals inhabiting the darkness of caves are generally blind and de-pigmented, regardless of the phylum they belong to. Survival in this environment is an enormous challenge, the most obvious being to find foo...
In blind cave-dwelling populations of Astyanax mexicanus, several morphological and behavioral shifts occurred during evolution in caves characterized by total and permanent darkness. Previous studies have shown ...
Authors: Jonathan Bibliowicz, Alexandre Alié, Luis Espinasa, Masato Yoshizawa, Maryline Blin, Hélène Hinaux, Laurent Legendre, Stéphane Père and Sylvie Rétaux
Extreme environmental conditions can give rise to extreme adaptations. We document growth, sexual maturation and fecundity in two species of African annual fish inhabiting temporary savanna pools.
Authors: Radim Blažek, Matej Polačik and Martin Reichard
Hox genes encode transcription factors that have an ancestral role in all bilaterian animals in specifying regions along the antero-posterior axis. In arthropods (insects, crustaceans, myriapods and chelicerat...
Most geophilomorph centipedes show intraspecific variability in the number of leg-bearing segments. This intraspecific variability generally has a component that is related to sex, with females having on avera...
A complex life cycle, such as complete metamorphosis, is a key innovation that can promote diversification of species. The evolution of a morphologically distinct larval stage is thought to have enabled insect...
Authors: Alison K Lee, Christie C Sze, Elaine R Kim and Yuichiro Suzuki
During their evolution towards a complete life cycle on land, stem reptiles developed both an impermeable multi-layered keratinized epidermis and skin appendages (scales) providing mechanical, thermal, and che...
The “9th Okazaki Biology Conference: Marine Biology II” held at the National Institute for Basic Biology (NIBB) in Okazaki, Japan and at the Okinawa Institute of Science and Technology (OIST) in Okinawa, Japan...
In a previous study, we showed that the cephalochordate amphioxus Branchiostoma floridae has localized maternal transcripts of conserved germ cell markers Vasa and Nanos in its early embryos. These results provid...
The de novo assembly of transcriptomes from short shotgun sequencesraises challenges due to random and non-random sequencing biases andinherent transcript complexity. We sought to define a pipeline for denovo tra...
Authors: Sarah Tulin, Derek Aguiar, Sorin Istrail and Joel Smith
Various shapes of gastropod shells have evolved ever since the Cambrian. Although theoretical analyses of morphogenesis exist, the molecular basis of shell development remains unclear. We compared expression p...
Authors: Keisuke Shimizu, Minoru Iijima, Davin HE Setiamarga, Isao Sarashina, Tetsuhiro Kudoh, Takahiro Asami, Edi Gittenberger and Kazuyoshi Endo
Hox genes are the key determinants of different morphogenetic events in all bilaterian animals. These genes are probably responsible for the maintenance of regenerative capacities by providing positional infor...
Authors: Elena L Novikova, Nadezhda I Bakalenko, Alexander Y Nesterenko and Milana A Kulakova
Hox genes are the family of transcription factors that play a key role in the patterning of the anterior-posterior axis of all bilaterian animals. These genes display clustered organization and colinear expressio...
Authors: Nadezhda I Bakalenko, Elena L Novikova, Alexander Y Nesterenko and Milana A Kulakova
The neural crest represents a highly multipotent population of embryonic stem cells found only in vertebrate embryos. Acquisition of the neural crest during the evolution of vertebrates was a great advantage, ...
In most species of aphid, female nymphs develop into either sexual or asexual adults depending on the length of the photoperiod to which their mothers were exposed. The progeny of these sexual and asexual fema...
Authors: Ryan D Bickel, Hillary C Cleveland, Joanna Barkas, Caitlin C Jeschke, Amelie A Raz, David L Stern and Gregory K Davis
Despite the devastating global impact of mosquito-borne illnesses on human health, very little is known about mosquito developmental biology. In this investigation, functional genetic analysis of embryonic sal...
Authors: Chilinh Nguyen, Emily Andrews, Christy Le, Longhua Sun, Zeinab Annan, Anthony Clemons, David W Severson and Molly Duman-Scheel
Genes encoding TCP transcription factors, such as CYCLOIDEA-like (CYC-like) genes, are well known actors in the control of plant morphological development, particularly regarding the control of floral symmetry. D...
Authors: Regine Claßen-Bockhoff, Raili Ruonala, Kester Bull-Hereñu, Neville Marchant and Victor A Albert
Morphological innovation is an elusive and fascinating concept in evolutionary biology. A novel structure may open up an array of possibilities for adaptation, and thus is fundamental to the evolution of compl...
Authors: Barbara MI Vreede, Jeremy A Lynch, Siegfried Roth and Élio Sucena
Little is currently known about wing pattern development in the butterfly family Pieridae, which consists mostly of black melanized elements on white or yellow/orange backgrounds. A single transcription factor...
Authors: Andrew M Stoehr, Joseph F Walker and Antónia Monteiro
On 12 February 1988 (by coincidence Charles Darwin’s birthday), a paper published in Science by Katherine Field, Rudy Raff, and colleagues presented the first credible molecular analysis of metazoan phylogeny bas...
Arthropod and vertebrate appendages appear to have evolved via parallel co-option of a plesiomorphic gene regulatory network. Our previous work implies that annelids evolved unrelated appendage-forming mechani...
Authors: Christopher J Winchell and David K Jacobs
The fish-tetrapod transition was one of the major events in vertebrate evolution and was enabled by many morphological changes. Although the transformation of paired fish fins into tetrapod limbs has been a ma...
Authors: Catherine Anne Boisvert, Jean MP Joss and Per E Ahlberg
Germline determination is believed to occur by either preformation or epigenesis. Animals that undergo germ cell specification by preformation have a continuous germline. However, animals with germline determi...
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
