Advertisement

Zoomorphology

, Volume 113, Issue 2, pp 69–78 | Cite as

Ontogeny and origin of the brooding system in Antarctic urechinid sea urchins (Echinodermata, Holasteroida)

  • Rich Mooi
  • Bruno David
Article

Summary

Echinoids usually broadcast gametes, and do not generally engage in a high degree of parental care. However, when they do, juveniles are typically maintained among the spines, or in shallow, external depressions in the test itself. The brooding Antarctic holasteroids Urechinus mortenseni and Plexechinus nordenskjoldi are bizarre exceptions: females develop an elaborate brooding system in which a small number of direct developing young are protected. Ontogeny of post-natal brooding urechinids is marked by profound divergence in the growth trajectories of male and female apical systems. In females, this leads to dramatic departures from the patterns found in all other echinoids. Otherwise, coronal skeleton allometry of males and females is almost identical. Juveniles in brood pouches grow larger than the diameter of the apical aperture through which they must pass to reach the external environment. The apical plates, from which the brooding system is suspended, “hinge” downward to enlarge the aperture, allowing the young to emerge from the female. A possible origin for the brooding system suggests derivation by centripetal plate addition from the ocular plates in the coronal skeleton. We develop a contrasting model for the origin of the brooding system that relies on a proposed homology between genital and periproctal elements of the apical system of echinoids and the more highly developed dorsal skeleton of other echinoderm classes.

Keywords

Developmental Biology External Environment Parental Care Dramatic Departure Growth Trajectory 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Agassiz A (1876) On viviparous Echini from the Kerguelen Islands. Proc Am Acad Arts Sci 11:231–236Google Scholar
  2. Barker M (1985) Reproduction and development in Goniocidaris umbraculum, a brooding echinoid. In: Keegan BF, O'Connor BDS (eds) Proc 5th int echinoderm conf, Balkema, Rotterdam, pp 207–214Google Scholar
  3. David B, Mooi R (1990) An echinoid that “gives birth”: morphology and systematics of a new Antarctic species, Urechinus mortenseni (Echinodermata, Holasteroida). Zoomorphology 110:75–89Google Scholar
  4. Emlet RB (1986) Facultative planktotrophy in the tropical echinoid Clypeaster rosaceus (Linnaeus) and a comparison with obligate planktotrophy in Clypeaster subdepressus (Gray) (Clypeasteroida: Echinoidea). J Exp Mar Biol Ecol 95:183–202Google Scholar
  5. Emlet RB, McEdward LR, Strathmann RR (1987) Echinoderm larval ecology viewed from the egg. In: Jangoux M, Lawrence JM (eds) Echinoderm studies vol 2. Balkema, Rotterdam, pp 55–136Google Scholar
  6. Gladfelter WB (1978) General ecology of the cassiduloid sea urchin Cassidulus caribbearum. Mar Biol 47:149–160Google Scholar
  7. Kier PM (1957) Tertiary Echinoidea from British Somaliland. J Paleontol 31:839–902Google Scholar
  8. Kier PM (1967) Sexual dimorphism in an Eocene echinoid. J Paleontol 41:988–993Google Scholar
  9. Märkel K (1981) Experimental morphology of coronar growth in regular echinoids. Zoomorphology 97:31–52Google Scholar
  10. Mespoulhé P (1992) Morphologie d'un échinide irregulier subantarctique de l'archipel des Kerguelen: ontogenèse, dimorphisme sexuel et variabilité. Thesis, Université de Bourgogne, 184 ppGoogle Scholar
  11. Mooi R (1986) Structure and function of clypeasteroid miliary spines (Echinodermata, Echinoides). Zoomorphology 106:212–223Google Scholar
  12. Mooir R (1989) Living and fossil genera of the Clypeasteroida (Echinoidea: Echinodermata): an illustrated key and annotated checklist. Smithson Contrib Zool 488:1–51Google Scholar
  13. Mooi R, David B (in press) Novel skeletal topologies are related to birth in Antarctic sea urchins. C R Acad Sci ParisGoogle Scholar
  14. Mortensen T (1909) Die Echinoiden. In: Report Deutsche Südpolar Expedition, 1901–1903. G Reimer, Berlin, pp 1–113Google Scholar
  15. Mortensen T (1928) A monograph of the Echinoidea I Cidaroida. Reitzel CA, Copenhagen, 647 ppGoogle Scholar
  16. Okazaki K, Dan K (1954) The metamorphosis of partial larvae of Peronella japonica Mortensen, a sand dollar. Biol Bull 106:83–99Google Scholar
  17. Parks AL, Parr BA, Chin JE, Leaf DS, Raff RA (1988) Molecular analysis of heterochronic changes in the evolution of direct developing sea urchins. J Evol Biol 1:27–44Google Scholar
  18. Philip GM, Foster RJ (1971) Marsupiate tertiary echinoids from south-eastern Australia and their zoogeographic significance. Palaontology 14:666–695Google Scholar
  19. Raff RA, Field KG, Ghiselin MT, Lane DJ, Oslen GJ, Pace NR, Parks AL, Parr BA, Raff EC (1988) Molecular analysis of distant phylogenetic relationships in echinoderms. In: Paul CRS, Smith AB (eds) Echinoderm phylogeny and evolutionary biology. Clarendon, Oxford, pp 29–41Google Scholar
  20. Schatt P (1985) L'édification de la face orale au cours du développement direct de Abatus cordatus, oursin incubant subantarctique. In: Keegan BF, O'Connor BDS (eds) Proc 5th int echinoderm conf. Balkema, Rotterdam, pp 339–345Google Scholar
  21. Smith AB (1984) Echinoid Palaeobiology. Allen and Unwin, London, 190 ppGoogle Scholar
  22. Wilkie IC (1984) Variable tensility in echinoderm collagenous tissues: a review. Mar Behav Physiol 11:1–34PubMedGoogle Scholar
  23. Wilkie IC, Emson RH (1988) Mutable collagenous tissues and their significance for echinoderm, palaeontology and phylogeny. In: Paul CRC, Smith AB (eds) Echinoderm phylogeny and evolutionary biology Clarendon, Oxford, pp 311–330Google Scholar
  24. Williams DHC, Anderson DT (1975) The reproductive system, embryonic development, larval development, and metamorphosis of the sea urchin Heliocidaris erythrogramma (Val.) (Echinoidea: Echinometridae). Aust J Zool 23:371–403Google Scholar

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Rich Mooi
    • 1
  • Bruno David
    • 2
  1. 1.Department of Invertebrate Zoology and GeologyCalifornia Academy of SciencesSan FranciscoUSA
  2. 2.U.R.A. CNRS 157Centre des Sciences de la TerreDijonFrance

Personalised recommendations