Dental topography of prosimian premolars predicts diet: A comparison in premolar and molar dietary classification accuracies.

Objectives: This study tests whether (1) premolar topography of extant "prosimians" (strepsirrhines and tarsiers) successfully predicts diet and (2) whether the combination of molar and premolar topography yields higher classification accuracy than using either tooth position in isolation.

Materials And Methods: Dental topographic metrics (ariaDNE, relief index, and orientation patch count rotated) were calculated for 118 individual matched-pairs of mandibular fourth premolars (P) and second molars (M). The sample represents 7 families and 22 genera.

Insights from macroevolutionary modelling and ancestral state reconstruction into the radiation and historical dietary ecology of Lemuriformes (Primates, Mammalia).

Background: Lemurs once rivalled the diversity of rest of the primate order despite thier confinement to the island of Madagascar. We test the adaptive radiation model of Malagasy lemur diversity using a novel combination of phylogenetic comparative methods and geometric methods for quantifying tooth shape.

Results: We apply macroevolutionary model fitting approaches and disparity through time analysis to dental topography metrics associated with dietary adaptation, an aspect of mammalian ecology which appears to be closely related to diversification in many clades.

Stem members of Platyrrhini are distinct from catarrhines in at least one derived cranial feature.

The pterion, on the lateral aspect of the cranium, is where the zygomatic, frontal, sphenoid, squamosal, and parietal bones approach and contact. The configuration of these bones distinguishes New and Old World anthropoids: most extant platyrrhines exhibit contact between the parietal and zygomatic bones, while all known catarrhines exhibit frontal-alisphenoid contact. However, it is thought that early stem-platyrrhines retained the apparently primitive catarrhine condition.

Brief communication: Effect of size biases in the coefficient of variation on assessing intraspecific variability in the prosimian skeleton.

This study examines the effect of a measurement size bias in coefficients of variation on the evaluation of intraspecific skeletal variability in a sample of eight prosimian species (Eulemur fulvus, Hapalemur griseus, Lemur catta, Varecia variegata, Galago senegalensis, Otolemur crassicaudatus, Nycticebus coucang, and Tarsius syrichta). Measurements with smaller means were expected to have higher coefficients of variation (CVs) due to the impact of instrumental precision on the ability to assess variability. This was evaluated by testing for a negative correlation between CVs and means in the total sample, within each species, and within each measurement, and by testing for the leveraging impact of small measurements on the significance of comparisons of variability between regions of the prosimian skeleton.