| Affiliation: | 1. Facultad de Ciencias del Mar, Universidad Autónoma de Sinaloa, Mazatlán, Sinaloa, Mexico Departamento de Oceanografía Biológica, Centro de Investigación Científica y Educación Superior de Ensenada Baja California, Ensenada, Baja California, Mexico;2. Instituto de Ciencias del Mar y Limnología, Unidad CDMX, Universidad Nacional Autónoma de México, Ciudad de Mexico, Mexico;3. Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolas de los Garza, Nuevo León, Mexico;4. Facultad de Ciencias del Mar, Universidad Autónoma de Sinaloa, Mazatlán, Sinaloa, Mexico;5. Departamento de Oceanografía Biológica, Centro de Investigación Científica y Educación Superior de Ensenada Baja California, Ensenada, Baja California, Mexico;6. Centro Regional de Investigación Pesquera, Instituto Nacional de Pesca, Mazatlán, Sinaloa, Mexico |
| Abstract: | We assessed the spatial pattern of genetic structure of smooth hammerhead shark Sphyrna zygaena in 10 localities from the Northern Mexican Pacific. A total of 35 haplotypes were identified in 129 sequences of the mtDNA control region. The results showed slight but significant genetic structure among localities (ΦST = 0.044, P < 0.001). In addition, the localities with highest number of juveniles were genetically different (ΦST = 0.058, P < 0.024), which may be representative of nursery areas. The genetic differentiation pattern can be associated to female philopatry and preference for particular birthing sites. Finally, historical demography shows that S. zygaena populations present a recent demographic expansion that occurred during glacial events in the late Pleistocene to early Holocene. |
