| In order to better understand the phylogenetic relationships of the insectivoran family Tenrecidae (Mammalia), morphological data were collected for living members of the family, two extinct tenrecid genera, nine other extinct placental mammals, and a variety of other endemic African and basal placental mammals, plus one marsupial. These data consisted of soft tissue characters based on the cranial arterial supply and anterior nasal anatomy, osteological characters from the cranium, dentition, and postcranium, and were combined with molecular sequences from the mitochondrial 12S rRNA gene. Cranial soft tissues were described using histological collections; individual cross sections from these collections were digitally photographed at regular intervals within specific anatomical regions, and were manipulated as 3D “stacks” using the public domain software NIH Image.; Morphologically, tenrecs show several autapomorphies in cranial vasculature and the anterior nasal region, such as the reduced superior stapedial artery in Potamogale, a reduced inferior stapedial artery in Tenrec and Hemicentetes, a papillary cartilage in Geogale, and an unpaired nasopalatine duct in Setifer and Echinops.; Based on these morphological and molecular data, hypotheses regarding the monophyly of the Insectivora, Afrotheria, Tenrecoidea, and Malagasy Tenrecidae were tested using total evidence parsimony analyses. Several initial assumptions about character treatment and phylogeny reconstruction were explicitly varied a priori in order to gauge the extent to which resulting clades were sensitive to these initial assumptions.; At the ordinal level, both the Insectivora and Afrotheria are sensitive to such initial assumptions as partition weight and multistate character ordering. However, the combined data consistently favor an association between tenrecs and golden moles; between the Malagasy Limnogale and the equatorial African potamogalines; and between Parageogale from the Kenyan Miocene and the extant, Malagasy Geogale. The presence of the latter two clades indicates that Malagasy tenrecids are not monophyletic, and supports the hypothesis that the current distribution of tenrecids has resulted from multiple dispersal events between Africa and Madagascar. The combined data do not support a clade consisting of Caribbean insectivorans and the Soricidae. |
