According to latest research, rodents can be divided into three monophyletic groups: the “mouse-related clade”, the “squirrel-related clade” and the Ctenohystrica. The latter are, since the beginning of the last century, at the center of intensive systematic research. Among them are the African Ctenodactylidae and “Phiomorpha”, the South American Caviomorpha and, as of late, also the Laotic Rock Rat Laonastes aenigmamus.
This project deals with the research of the morphology of selected Ctenohystrica, particularly with regard to systematics, function and ecology. Using reconstructed ground plans of monophyletic relationships it aims at distinguishing between convergent functional adaptations to specific ways of life and phylogenetically determined character states.
This will be done using classic preparation, histological serial sections, µCT-scans and contrast staining of non-mineralized tissues. 3D reconstructions are of use for both the demonstrative and comprehensible representation as well as the quantification of morphological structures. I will pay special attention to the ontogenetic comparison of fetal, perinatal and adult stages, without which the interpretation of the evolution of characters, especially at rodents, could not be done properly.
To verify the morphological results, free range studies will be carried out simultaneously.
Thryonomys swinderianus, perinatal stage: 3D-reconstruction of the middle and inner ear from histological serial sections. Dorsomedial view
Octodon degus, comparison of perinatal (histological section) and adult stage (µCT-scan)
Tröscher, A., Maier, W., Ruf, I., Hugot, J.P., Böhme, M. (2015): The epitensoric chorda tympani of Laonastes aenigmamus (Rodentia, Diatomyidae) and its phylogenetic implications. Mammalian Biology 80: 96-98, http://dx.doi.org/10.1016/j.mambio.2014.12.008
Maier, W., Tröscher, A., Ruf. I. (2012): The entotympanic of Equus caballus (Perissodctyla, Mammalia), Mammalian Biology, dx.doi.org/10.1016/j.mambio.2012.05.002