Evolution of the cephalopod head complex by assembly of multiple molluscan body parts: Evidence from Nautilus embryonic development

  title={Evolution of the cephalopod head complex by assembly of multiple molluscan body parts: Evidence from Nautilus embryonic development},
  author={Shuichi Shigeno and Takenori Sasaki and Takeya Moritaki and Takashi Kasugai and Michael Vecchione and Kiyokazu Agata},
  journal={Journal of Morphology},
Cephalopod head parts are among the most complex occurring in all invertebrates. [] Key Method Using a specialized aquarium system, we successfully obtained a series of developmental stages that enabled us to test previous controversial scenarios. Our results demonstrate that the embryonic organs exhibit body plans that are primarily bilateral and antero-posteriorly elongated at stereotyped positions. The distinct cephalic compartment, foot, brain cords, mantle, and shell resemble the body plans of…

The origins of cephalopod body plans: A geometrical and developmental basis for the evolution of vertebrate-like organ systems

The cephalopod body plans are characterized, set against those of the other bilaterians, in the light of recent data from paleontology, embryology, and molecular gene expression patterns to provide a review and new interpretation with an emphasis on the topographic transition of the soft parts that is shaped by a shared concentric circle or ovoid pattern in the embryos and adults of extant or fossil molluscs.

Cephalopod origin and evolution: A congruent picture emerging from fossils, development and molecules

  • B. KrögerJ. VintherD. Fuchs
  • Geography, Environmental Science
    BioEssays : news and reviews in molecular, cellular and developmental biology
  • 2011
A growing body of evidence from the fossil record, embryology and Bayesian molecular divergence estimations provides a comprehensive picture of cephalopods' origins and evolution.

The cephalopod arm crown: appendage formation and differentiation in the Hawaiian bobtail squid Euprymna scolopes

The early outgrowth and differentiation of the E. scolopes arm crown shows similarities to the related, yet derived cephalopod Octopus vulgaris, raising the question of whether these similarities reflect a recruitment of similar molecular patterning pathways.

Evolution of limb development in cephalopod mollusks.

It is shown that all three axes of cuttlefish limbs are patterned by the same signaling networks that act in vertebrates and arthropods, although they evolved limbs independently.

A novel role for dpp in the shaping of bivalve shells revealed in a conserved molluscan developmental program.

Evolution of limb development in cephalopod mollusks

It is shown that all three axes of cuttlefish limbs are patterned by the same signaling networks that act in vertebrates and arthropods, although they evolved limbs independently.

The scaphopod foot is ventral: more evidence from the anatomy of Rhabdus rectius (Carpenter, 1864) (Dentaliida: Rhabdidae)

Based on the orientation of the digestive tract and the dorso-ventral muscles, it is found further evidence to support the interpretation that the concave side of the scaphopod shell is anterior (the site of the mouth) and the foot is ventral.

Cephalopod Brains: An Overview of Current Knowledge to Facilitate Comparison With Vertebrates

A critical analysis of cephalopod neural systems showing similarities to the cerebral cortex, thalamus, basal ganglia, midbrain, cerebellum, hypothalamus, brain stem, and spinal cord of vertebrates is described.

POU genes are expressed during the formation of individual ganglia of the cephalopod central nervous system

The expression of four POU genes in unique spatiotemporal combinations during early neurogenesis and sensory organ development of the pygmy squid Idiosepius notoides suggests that they fulfill distinct tasks during early brain development.



Cephalopod Hox genes and the origin of morphological novelties

Developmental expression patterns for eight out of nine Hox genes in the Hawaiian bobtail squid Euprymna scolopes are examined by whole-mount in situ hybridization, showing that Hox orthologues have been recruited multiple times and in many ways in the origin of new cephalopod structures.

Molluscan engrailed expression, serial organization, and shell evolution

In situ hybridization and antibody studies show iterated engrailed‐gene expression in transverse rows of ectodermal cells bounding plate field development and spicule formation in the chiton, Lepidochitona caverna, as well as in cells surrounding the valves and in the early development of the shell hinge in the clam, Transennella tantilla.

The expression of an engrailed protein during embryonic shell formation of the tusk‐shell, Antalis entalis (Mollusca, Scaphopoda)

The single anlage of the scaphopod protoconch contradicts earlier hypotheses of a monophyletic taxon Diasoma (Scaphopoda + Bivalvia), which has been mainly based on the assumption of a primarily bilobed shell in both taxa.

The cephalopod nervous system: What evolution has made of the molluscan design

Special emphasis will be given to those features of the cephalopod nervous system that are unusual or even unique, often rivaling the equivalent parts of the vertebrate nervous system in sophistication; some of these features may characterize higher brain and nervous system function.

Biology of early life stages in cephalopod molluscs.

  • S. von Boletzky
  • Environmental Science, Biology
    Advances in marine biology
  • 2003
Investigations into dispersal and recruitment are of particular interest to fishery biology, but they are also important for ecological biogeography.

Early Ontogeny of the Japanese Common Squid Todarodes pacificus (Cephalopoda, Ommastrephidae) with Special Reference to its Characteristic Morphology and Ecological Significance

Four distinct stages, namely, paralarval stage 1, 2, 3, and juvenile stage are proposed based on such morphological features, and they are compared with those in other cephalopods.


It is suggested that some of the anterior or posterior cognates have been lost in some lineages, most notably in Caudofoveata, while the medial cognates showed both losses and duplications.

Evidence for a clade composed of molluscs with serially repeated structures: Monoplacophorans are related to chitons

The first molecular data on monoplacophorans, analyzed together with the largest data set of molluscs ever assembled, clearly illustrate that monoplacs and chitons form a clade and may have important implications for metazoan evolution.