“…There is widespread opinion that sponges do not disperse far (Maldonado and Young, 1996;Lindquist et al, 1997;Uriz et al, 1998;Maldonado and Bergquist, 2002), despite the fact that different sponge species exhibit a range of reproductive strategies (Maldonado and Bergquist, 2002) and life histories that possibly result in a range of dispersal outcomes. The existence of sponge species with cosmopolitan distributions has stood in apparent contradiction to the prediction that sponges are capable of only short-distance dispersal but a number of studies have demonstrated that cosmopolitanism is often just a case of boverconservative systematicsQ due to the paucity of morphological characters useful for fine-scale species discrimination (Sole-Cava and Thorpe, 1986;BouryEsnault et al, 1992;Sole-Cava et al, 1992;Klautau et al, 1994Muricy et al, 1996;Wörheide et al, 2003). Most cosmopolitan species [with notable exceptions as given in Lazoski et al (2001)], when evaluated using molecular genetic techniques, are found to encompass cryptic species diversity and high levels of population genetic structure on geographic scales more compatible with hypotheses of limited dispersal ability (Sole-Cava and Thorpe, 1986;BouryEsnault et al, 1992;Sole-Cava et al, 1992;Klautau et al, 1994Muricy et al, 1996;Wörheide et al, 2003).…”