. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 504 L. A. LEVIN \ A Mission Bay, CA N = 67 o Big Slough, TX N = 73 T Tar Landing, NC N = 50 FEB 83 • Merl, R\ N 50 • New Bedford, MA N = 50. 10 20 30 DAYS FOLLOWING RELEASE FROM BROOD POUCH 40 FIGURE 5. Planktonic period of Streblospio benedicti larvae raised individually in glass tubes without substrate at 20°C. Larvae were fed mixed phytoplankton cultures. Each line represents survivorship of individuals from a single brood or from pooled broods (Mission Bay, California, 3 broods and Big Slough, Texas, 7 broods). Loss from
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 504 L. A. LEVIN \ A Mission Bay, CA N = 67 o Big Slough, TX N = 73 T Tar Landing, NC N = 50 FEB 83 • Merl, R\ N 50 • New Bedford, MA N = 50. 10 20 30 DAYS FOLLOWING RELEASE FROM BROOD POUCH 40 FIGURE 5. Planktonic period of Streblospio benedicti larvae raised individually in glass tubes without substrate at 20°C. Larvae were fed mixed phytoplankton cultures. Each line represents survivorship of individuals from a single brood or from pooled broods (Mission Bay, California, 3 broods and Big Slough, Texas, 7 broods). Loss from the plankton is taken to occur when larvae first permanently settle onto the tube bottom. at any time after release is similar for larvae from different females and even from different populations (Fig. 5). Interbreeding potential Sex-blind pairings demonstrated that S. benedicti is a dioecious species which, at least under laboratory conditions, does not reproduce hermaphroditically or asexually. Analysis of nine pairings between Mission Bay juveniles and New England (MERL or New Bedford) juveniles after 2 months in culture revealed 4 male/female pairs, 4 female/female pairs, and 1 male/male pair. None of the single sex pairs showed any evidence of reproduction though all individuals contained ripe gametes. All male/ female pairs had reproduced successfully, two producing lecithotrophic larvae by Mission Bay females and 2 producing planktotrophic larvae by New England females. The F[ larvae from crosses in both directions settled and successfully produced F2 larvae by interbreeding among themselves. Additional inter-development mode reciprocal matings were conducted successfully between individuals from Big Slough X MERL, -X New Bedford, and -X Copano Bay, and between Tar Landing (lecitho- trophs) X MERL. Results of these crosses will be presented in a later paper. They are mentioned here to demonstrate the interfertility of S. benedicti populations. DISCUSSION The obser
Size: 2037px × 1227px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
