TL;DR: Comparison with fossils suggests that the Fayum parapithecids are not specially related to the Old World monkeys, while other undoubted Fayum 'hominoids' may share derived features with monkeys.
Abstract: The application of cladistic methods (especially a concentration on shared derived rather than ancestral characters) permits the distinction of four dental and two cranial morphocytes among the Cercopithecidae. Comparison with fossils suggests that the Fayum parapithecids are not specially related to the Old World monkeys, while other undoubted Fayum 'hominoids' may share derived features with monkeys. Miocene Victoriapithecus 'species' may document a stage very close to the split between Colobinae and Cercopithecinae. Later African colobines appear to form a monophyletic group, more arboreal than the extinct European branch; Asian forms may be specially related to the latter. Among the Cercopithecinae, after a Miocene separation from the high-forest Cercopithecini, the Papionini divided into three groups: geladas, sub-Saharan Papio-related 'baboons' and Mediterranean-Eurasian macaque relatives; each of these underwent Plio-Pleistocene adaptive radiations and subsequent taxonomic diminution.
TL;DR: A comparison of Estimation Accuracy with Previous Studies and the Applications of Paleobiological Applications of the authors' Estimates shows that sex Dimorphism and Evolution of Cercopithecid Mass through Time through Time are major themes.
Abstract: ............................................ 4 Introduction ............................................. 4 Institutional Abbreviations ............................................. 6 Materials .............................................. 7 Postcrania ............................................. 7 Craniodental Data ............ ................................. 9 Compiled Mass Data ............... .............................. 10 Statistical Methods ............................................. 16 Mass Estimation ............................................. 16 Choice of Comparative Samples for Estimating Fossil Masses ....... ............. 17 Estimation Model Construction and Evaluation ................. ................... 18 Postcranial Sample ............................................. 18 Craniodental Sample ............... .............................. 18 Identifying Reliable Estimators ............................................. 18 Evaluation of Estimator Variables ............................................. 30 Comparing Estimator Performance Between Anatomical Regions ...... ............ 30 Comparison of Estimation Accuracy with Previous Studies ........ ............... 31 Scaling of Predictor Variables .............................................. 38 Postcranial Scaling ............. ................................ 43 Dental Scaling ............................................. 46 Cranial Scaling ............................................. 48 Implications for Estimating Body Mass ......................................... 49 Estimated Mass in Fossil Cercopithecid Taxa ....................................... 50 Colobinae ....................................................... 50 Africa ............................................. 50 Eurasia ............................................. 57 Cercopithecinae ............................................. 62 Eurasia ............................................. 62 Africa ............................................. 67 Taxa other than Theropithecus ............................................. 67 Taxa of the Theropithecus clade ............................................. 77 Victoriapithecinae ....................................................... 82 Discussion ............................................. 84 Some Theoretical and Methodological Questions ............ .................... 84 Selection of Variables ................. ............................ 84 Selection of Models .............. ............................... 86 The Form of the Answer ............................................. 86 Interregional Estimation Comparisons .......................................... 87 Paleobiological Applications of our Estimates ............... .................... 87 Sex Dimorphism ............................................. 88 Evolution of Cercopithecid Mass through Time ............. .................... 88 Extinct Cercopithecid Mass and Energetics ................... .................. 92 Summary ............................................. 93 Acknowledgments ............................................. 97 References ............................................. 98 Appendices ............................................. 105
TL;DR: It is surmised that binocular competition at the geniculate or cortical level is operative in both unilateral lid closure and strabismus and causes similar changes in the primate visual system.
Abstract: Amblyopia can be produced in rhesus monkeys by suturing the lids of one eye (visual deprivation amblyopia) or by producing artificial esotropia (strabismic amblyopia) during visual immaturity. Sections from retinas, lateral geniculate nuclei (LGN), and areas 17 and 18 of the visual cortex from monkeys with behaviorally proved amblyopia and cortical neurophysiologic changes were examined histologically and compared with normal tissue. Other than significant reduction in cell section areas in all layers of the LGN that received input from the deprived or esotropic eye, we were unable to demonstrate anomalies elsewhere in the visual system. In spite of the difference in pathogenesis of visual deprivation and strabismic amblyopia, the similarity of findings in the LGN of monkeys with both types of amblyopia suggests a common mechanism. Since dissimilarity of visual input from the two eyes caused by unilateral lid suture has been shown to affect geniculate cell size in visually immature kittens, we surmise that binocular competition at the geniculate or cortical level is operative in both unilateral lid closure and strabismus and causes similar changes in the primate visual system.