Genotype-specific growth of hard clams (genus Mercenaria) in a hybrid zone: variation among habitats
Arnold, W.S.; Bert, T.M.; Marelli, D.C.; Cruz-Lopez, H.; Gill, P.A. (1996). Genotype-specific growth of hard clams (genus Mercenaria) in a hybrid zone: variation among habitats. Mar. Biol. (Berl.) 125(1): 129-139. https://dx.doi.org/10.1007/BF00350767
In: Marine Biology: International Journal on Life in Oceans and Coastal Waters. Springer: Heidelberg; Berlin. ISSN 0025-3162; e-ISSN 1432-1793, more
|  |
| Keywords |
Abundance
Animal products > Shells
Animals > Invertebrates > Mollusca > Bivalvia > Veneridae > Mercenaria
Audiovisual materials > Graphics > Graphs > Growth curves
Fauna > Aquatic organisms > Aquatic animals > Shellfish > Marine organisms > Marine molluscs
Genotypes
ASW, USA, Florida, Indian River Lagoon [Marine Regions]
Marine/Coastal |
| Authors | | Top |
- Arnold, W.S.
- Bert, T.M.
- Marelli, D.C.
|
- Cruz-Lopez, H.
- Gill, P.A.
|
|
| Abstract |
Shell growth rate is an important component of fitness in bivalve molluscs. Using the ohgr parameter computed from the von Bertalanffy growth equation, we quantitatively compared rates of annual shell grwoth among the hard clams Mercenaria mercenaria, M. campechiensis, and their hybrids sampled from a variety of habitats in the Indian River lagoon, Florida, USA, a zone of species overlap and natural hybridization. Our results indicate that the classical paradigm describing hard clam growth, in which growth rate is fastest in M. campechiensis, intermediate in hybrids, and slowest in M. mercenaria is not supported in the Indian River lagoon. Instead, M. campechiensis has a growth advantage in deep-water habitats in the northern section of our study area. In the central and southern sections of our study area, hybrids have a growth advantage over M. mercenaria in shallow-water habitats, but M. mercenaria has a growth advantage over hybrids in deep-water habitats. In all other sampled habitats, either growth rate among genotype classes is equal, or M. mercenaria has a growth advantage. This complex relationship between genotype and habitat-specific growth provides a mechanism for selection to act on hard clams in the Indian River. |
|
