Ontogenetic variation in the skulls of Caiman: the case of Caiman latirostris and Caiman yacare (Alligatoridae, Caimaninae)
Ontogenetic variation in the skulls of Caiman: the case of Caiman latirostris and Caiman yacare (Alligatoridae, Caimaninae)
Caiman is one of the five extant genera of alligatorid crocodylians. While several quantitative and qualitative studies exist on morphological variation in the genus, little is known about ontogenetic effects. Here, we quantify ontogenetic variation in morphology for Caiman yacare and C. latirostris in a phylogenetic context. A linear regression analysis on twelve skull measurements of C. yacare and C. latirostris against a measure of size (the first axis of a PCA of all variables) showed high correlation coefficients (r2 =0.89–0.99) and negative allometry. Eight allometric trajectories showed common slopes at different intercepts, reflecting a common ontogenetic pattern of morphological growth fixed early in ontogeny. The anterior width of the snout and the posterior width of the skull table are suitable to discriminate between the two species. The relationship between snout width and snout length is isometric in C. latirostris while it is negatively allometric in C. yacare. These results confirm that the snout shape is a distinctive feature between species established early in ontogeny. The narrowing and lengthening of the snout in C. yacare during ontogeny results in adult forms widely represented in other extant taxa within the genus. The broader and shorter snout in C. latirostris is probably an autapomorphic feature of this species within Caimaninae.
Fil: Fernandez Blanco, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina
Fil: Bona, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina
Fil: Olivares, Adriana Itati. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Área Zoología; Argentina
Fil: Desojo, Julia Brenda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina
Allometry, https://purl.org/becyt/ford/1.6, Ontogeny, Caiman Yacare, https://purl.org/becyt/ford/1, Cranial Variation, Caiman Latirostris
Allometry, https://purl.org/becyt/ford/1.6, Ontogeny, Caiman Yacare, https://purl.org/becyt/ford/1, Cranial Variation, Caiman Latirostris
selected citations These citations are derived from selected sources.This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).0 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Average influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Average impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Average
Citations provided by BIP!Popularity provided by BIP!