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echinoderms have such low mass-specific respiration rates that may enable them to disperse for months, or even years (ranging from 10 months to 5 years) relying exclusively on the reserves of the egg. Hoegh-Guldberg & Emlet (1997) investigated energy use during development of the lecithotrophic echinoid species Heliocidaris erythrogramma and the planktotrophic H. tuberculata. They observed that the energy required to generate a juvenile on a per mass basis in the species with planktotrophic larvae is essentially the same as that in the species with pelagic, lecithotrophic larvae, when the body size of juveniles is taken into account. Marsh et al. (1999) established that the lack of particulate food resource does not appear to cause a “starvation” stress on the early larvae of the Antarctic echinoid Sterechinus neumayeri (Müller). This indicated that feeding larval stages were not dependent on the availability of phytoplankton to complete early development. In addition, there is great potential for embryos and larvae to uptake dissolved organic material, which might also reduce the demand for resources of particulate food. It is likely that the same phenomenon occurs in the cold waters of the deep sea as in Antarctica. Species with planktotrophic development may not necessarily spend any longer time in the plankton than pelagic lecithotrophs. Evidence that lecithotrophy does not limit deep-sea dispersal is provided by studies on the genetics of hydrothermal vent organisms (Black et al. 1997; Craddock et al. 1997; Vrijenhoek, 1997). Analysis of allozymes in four species of archaeogastropod limpets with nonplanktotrophic modes of development provided results contrary to the prediction that dispersal should occur in a “stepping-stone” mode. Among those four species two of them did not exhibit the expected decline in rates of gene flow with increasing geographic distances between sampled localities, suggesting that the lecithotrophic larvae of these species are capable of dispersal over very long distances (Craddock et 19
al., 1997). In a review (Vrijenhoek, 1997) citing hydrothermal vent-endemic molluscs, two species of bivalves and two species of limpets showed evidence of high rates of gene flow that were not restricted by the topology of the ridge system or by geographical distance. In the deep sea, species with planktotrophic larval development may be restricted to regions where there is sufficiently high surface production in order to produce an important amount of fine detrital food at bathypelagic and abyssopelagic depths. Therefore planktotrophic larvae could be limited by food in oligotrophic areas, whereas lecithotrophic larvae may survive even if advected to areas of low productivity using energy stored internally (Young et al., 1997). A very important case to mention regarding planktotrophy and widespread distribution is the deep-sea synaptid holothurian Protankyra brychia Verrill, which essentially has a cosmopolitan distribution. The oocyte diameters of P. brychia indicate planktotrophic larval development or lecithotrophic larval development followed by planktotrophy (Billet, 1991; Pearse, 1994). Pawson et al. (2003) presented evidence that this species has a near surface planktotrophic larval stage which had been reported in the literature as the Giant Auricularia larva Auricularia nudibranchiata Chun (Chun, 1896; Oshima, 1911; MacBride, 1920; Inaba, 1934; Garstang, 1939). 1.3- Deep-water formation and species dispersal Developmental mode is not the only factor that might determine dispersal distance. Scheltema (1986b) established that “the maximum potential distance that a larva can be dispersed and the likelihood that it survives to settlement is related to (a) the length of its planktonic life and (b) to the rate and direction of the currents that transport it”. 20
Page 1 and 2: University of Southampton Research
Page 3 and 4: Graduate School of the National Oce
Page 5 and 6: UNIVERSITY OF SOUTHAMPTON ABSTRACT
Page 7 and 8: Marthasterias glacialis (ECHINODERM
Page 9 and 10: Acknowledgments I know everybody sa
Page 11 and 12: Prière de l’étoile de mer Seign
Page 13 and 14: species of asteroid Patiriella para
Page 15 and 16: embryonic tolerances could determin
Page 17 and 18: dispersed over great distances and
Page 19: lecithotrophic development. The pre
Page 23 and 24: Although larval dispersal and settl
Page 25 and 26: larvae of shallow water echinoids f
Page 27 and 28: few hours, whereas other species su
Page 29 and 30: een defined as a unique sequence of
Page 31 and 32: therefore a developing form may wel
Page 33 and 34: adults” that have the definitive
Page 35 and 36: The dipleurula is the hypothetical
Page 37 and 38: among tunicate tadpoles, sponge and
Page 39 and 40: Fig.2.4. Bipinnaria larvae of the a
Page 41 and 42: In marine invertebrates there is a
Page 43 and 44: independent of habitat or mode of n
Page 45 and 46: whether juveniles derived from larv
Page 47 and 48: and the northern Mediterranean have
Page 49 and 50: Wares (2001) performed phylogenetic
Page 51 and 52: Fig. 3.2. A. Marthasterias glaciali
Page 53 and 54: 3.2.2- Temperature/pressure effects
Page 55 and 56: Pressure was applied using an Enerp
Page 57 and 58: Fig. 3.7. Bippinaria larvae of Mart
Page 59 and 60: X Data were abnormal. At 150 and 20
Page 61 and 62: X Data all the embryos were abnorma
Page 63 and 64: X Data blastulae, at 200atm 90% of
Page 65 and 66: 50atm more than 90% of embryos were
Page 67 and 68: Those data (Young et al., 1997; Ped
Page 69 and 70: Percentage of individuals swimming
Page 71 and 72:
that settling invertebrate larvae d
Page 73 and 74:
CHAPTER FOUR- REPRODUCTIVE FEATURES
Page 75 and 76:
In 1973, Vance proposed a theoretic
Page 77 and 78:
Species Volume Energy Dev Class Ref
Page 79 and 80:
4.1.2- Body Size The reproductive o
Page 81:
Species Depth of max. Depth range (
Page 84 and 85:
arm, and the minor radius (r), from
Page 86 and 87:
From Eqs.1 and 3 we obtain the esti
Page 88 and 89:
Data on maximum body size, maximum
Page 90 and 91:
250 200 Body size (mm) 150 100 50 0
Page 92 and 93:
Fig. 4.7. Hierarchical cluster anal
Page 94 and 95:
(Hymenaster membranaceus Thomson).
Page 96 and 97:
gamete production at low population
Page 98 and 99:
varies depending on the vitellogeni
Page 100 and 101:
size, high fecundity, small egg siz
Page 102 and 103:
strategy described by Winemiller an
Page 104 and 105:
It seems that evolutionary features
Page 106 and 107:
strategy stablished by the Winemill
Page 108 and 109:
which normal embryonic/larval devel
Page 110 and 111:
Larval dispersal from eight populat
Page 112 and 113:
These results are very important si
Page 114 and 115:
possibility. The opportunistic spec
Page 116 and 117:
hypothesis that the Mesozoic and ea
Page 118 and 119:
Barnes, H. and H.T. Powell. 1951. T
Page 120 and 121:
Chester, C.M. 1996. The effect of a
Page 122 and 123:
Crisp, D.J. 1978. Genetic consequen
Page 124 and 125:
David, B., A. Guille, J-P. Féral a
Page 126 and 127:
Grant, A. 1983. On the evolution of
Page 128 and 129:
Inaba, D. 1934. On some holothurian
Page 130 and 131:
of the 6 th International Echinoder
Page 132 and 133:
Lieberkind, I. 1926. Ctenodiscus au
Page 134 and 135:
McEdward, L.R. and S.F. Carson. 198
Page 136 and 137:
Minchin, D. 1987. Sea-water tempera
Page 138 and 139:
Pawson, D.L. 1976. Some aspects of
Page 140 and 141:
Pingree. R.D., B. Sinha and C.R. Gr
Page 142 and 143:
Savidge, G., H.J. Lennon, and A.D.
Page 144 and 145:
Shilling, F.M. and D.T. Manahan. 19
Page 146 and 147:
Turner, R.L. and J.M. Lawrence. 197
Page 148 and 149:
Vickery, M.S. and J.B. McClintock 2
Page 150 and 151:
(Eds.): Reproduction Genetics and D
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