Morphometric analysis of the black rat, Rattus rattus, from Congreso Island (Chafarinas Archipelago, Spain)
Black rats, Rattus rattus, from Chafarinas Archipelago constitute one of the westernmost insular populations of the species in the Mediterranean region. To evaluate the influence of insular conditions on body and skull dimensions, the biometric characteristics of a sample from Congreso island were d...
| Autores: | , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 2000 |
| País: | España |
| Institución: | Universitat Autònoma de Barcelona |
| Repositorio: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglés |
| OAI Identifier: | oai:ddd.uab.cat:1810 |
| Acceso en línea: | https://ddd.uab.cat/record/1810 |
| Access Level: | acceso abierto |
| Palabra clave: | Craniometry Island syndrome Mediterranean islands Rodents Somatometry Craneometría Islas mediterráneas Rattus rattus Roedores Síndrome de insularidad Somatometría |
| Sumario: | Black rats, Rattus rattus, from Chafarinas Archipelago constitute one of the westernmost insular populations of the species in the Mediterranean region. To evaluate the influence of insular conditions on body and skull dimensions, the biometric characteristics of a sample from Congreso island were determined and compared with nearby mainland populations (Málaga -southeastern Iberia- and Morocco). Results show that Congreso specimens are similar in size to Iberian specimens and in skull shape to Morocco animals. Considering this later fact and the geographical proximity between Chafarinas and the Morocco coastline, it seems likely that Congreso black rats had their source in North-African populations. The size similarity between Iberian and Congreso rats does not appear to be the expression of a genetic relationship but a biometric convergence. Actually, the specimens from Málaga correspond to one of the largest mainland forms of R. rattus from western Europe, and the size of Congreso rats might constitute another case of gigantism that appears as an adaptive response to insularity in black rat populations from small western Mediterranean islands. Lack of interspecific competition and low predation pressure in Congreso could have contributed to the black rat size increase. |
|---|