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Full-Text Articles in Life Sciences
Escorting Of Mother-Calf Pairs Of Humpback Whales (Megaptera Novaeangliae) In The Colombian Pacific During The Breeding Season, Natalia Botero Acosta
Escorting Of Mother-Calf Pairs Of Humpback Whales (Megaptera Novaeangliae) In The Colombian Pacific During The Breeding Season, Natalia Botero Acosta
Dissertations
Humpback whales (Megaptera novaeangliae) belonging to the “breeding G-stock” annually migrate from the Antarctic Peninsula and southern Chile to the southeastern Pacific to reproduce. Associations between mother-calf pairs and escorts were examined in the Gulf of Tribugá, northern Colombian Pacific, using photo-identification and behavioral/spatial sampling. Research hypotheses included: 1. The association between cows and escorts is short-lived, consistent with a male reproductive strategy, 2. The presence of escort(s) elicits a behavioral response from mother-calf pairs and, 3. The patterns of spatial distribution reflect the spatial segregation of maternal females. Groups were classified as mother-calf pairs (Mc), mother, calf …
Species Delimitation, Phylogenetics, And Biogeography Of The Catfish Genus Rhamdia Bleeker (Heptapteridae) Of Central America And The Trans-Andean Region Of Colombia, Carmen Liliana Hernández Torres
Species Delimitation, Phylogenetics, And Biogeography Of The Catfish Genus Rhamdia Bleeker (Heptapteridae) Of Central America And The Trans-Andean Region Of Colombia, Carmen Liliana Hernández Torres
Dissertations
A recent taxonomic revision of the Neotropical catfish genus Rhamdia (Pisces: Siluriformes: Heptapteridae) reduced a number of described species to synonymy, especially under a broadly circumscribed R. quelen. Evidence is presented here from DNA sequence data, external and internal morphology, and morphometrics that argues for the recognition of R. guatemalensis in Central and northern South America and R. saijaensis and R. cinerascens in the Pacific drainages of Colombia and Ecuador, respectively. The DNA data indicate that all trans-Andean samples form a monophyletic group, within which there are separate clades corresponding to R. laticauda and the synonymized R. guatemalensis, …
The Effects Of Climate Variability On The Structure Of The Phytoplankton Community In Tumaco Bay, Colombia, Ingrid Garcia-Hansen Honkala
The Effects Of Climate Variability On The Structure Of The Phytoplankton Community In Tumaco Bay, Colombia, Ingrid Garcia-Hansen Honkala
Dissertations
Spatiotemporal variability in the diatom and dinoflagellate community structure and chlorophyll a (chl a) concentrations in Tumaco Bay during the 1993-2005 period was related clearly to seasonal and interannual variability in environmental conditions due to the migration of the Inter-tropical Convergence Zone (ITZC) and the influence of El Nino Southern Oscillation (ENSO) events. A total of 134 species of diatoms that belong to 57 genera, and 78 species of dinoflagellates that belong to 25 genera were identified during the survey. The diatom community was the dominant group in the waters of the bay, being the most abundant with the greatest …