Published in Biol Bull, in 1999, in volume 196, pages 153-162
Created: 2010-01-07, modified: 2011-06-21
doi:10.2307/1542561
Published in Biol Bull, in 2000, in volume 198, pages 272-283
Created: 2010-01-07, modified: 2011-06-21
doi:10.2307/1542530