Major national and international critiques of the medical curriculum in the 1980s noted the following significant flaws: (1) over-reliance on learning by rote memory, (2) insufficient exercise in analysis and synthesis/conceptualization, and (3) failure to connect the basic and clinical aspects of training. It was argued that the invention of computers and related imaging techniques called to question the traditional instruction based on the faculty-centered didactic lecture. In the ensuing reform, which adopted case-based, small group, problem-based learning, time allotted to anatomical instruction was severely truncated. Many programs replaced dissection with prosections and computer-based learning. We argue that cadaver dissection is still necessary for (1) establishing the primacy of the patient, (2) apprehension of the multidimensional body, (3) touch-mediated perception of the cadaver/patient, (4) anatomical variability, (5) learning the basic language of medicine, (6) competence in diagnostic imaging, (7) cadaver/patient-centered computer-assisted learning, (8) peer group learning, (9) training for the medical specialties. Cadaver-based anatomical education is a prerequisite of optimal training for the use of biomedical informatics. When connected to dissection, medical informatics can expedite and enhance preparation for a patient-based medical profession. Actual dissection is equally necessary for acquisition of scientific skills and for a communicative, moral, ethical, and humanistic approach to patient care. Anat Rec (New Anat) 269:20-32, 2002.

In a recent study Diogo & Abdala [(2007) J Morphol 268 , 504-517] reported the results of the first part of a research project on the comparative anatomy, homologies and evolution of the pectoral muscles of osteichthyans (bony fish and tetrapods). That report mainly focused on actinopterygian fish but also compared these fish with certain non-mammalian sarcopterygians. This study, which reports the second part of the research project, focuses mainly on sarcopterygians and particularly on how the pectoral and forelimb muscles have evolved during the transitions from sarcopterygian fish and non-mammalian tetrapods to monotreme and therian mammals and humans. The data obtained by our own dissections of all the pectoral and forelimb muscles of representative members of groups as diverse as sarcopterygian fish, amphibians, reptiles, monotremes and therian mammals such as rodents, treeshrews, colugos and primates, including humans, are compared with the information available in the literature. Our observations and comparisons clearly stress that, with regard to the number of pectoral and forelimb muscles, the most striking transition within sarcopterygian evolutionary history was that leading to the origin of tetrapods. Whereas extant sarcopterygian fish have an abductor and adductor of the fin and a largely undifferentiated hypaxial and epaxial musculature, extant salamanders such as Ambystoma have more than 40 pectoral and forelimb muscles. There is no clear increase in the number of pectoral and forelimb muscles within the evolutionary transition that led to the origin of mammals and surely not to that leading to the origin of primates and humans.

The mammalian facial muscles are a subgroup of hyoid muscles (i.e. muscles innervated by cranial nerve VII). They are usually attached to freely movable skin and are responsible for facial expressions. In this study we provide an account of the origin, homologies and evolution of the primate facial muscles, based on dissections of various primate and non-primate taxa and a review of the literature. We provide data not previously reported, including photographs showing in detail the facial muscles of primates such as gibbons and orangutans. We show that the facial muscles usually present in strepsirhines are basically the same muscles that are present in non-primate mammals such as tree-shrews. The exceptions are that strepsirhines often have a muscle that is usually not differentiated in tree-shrews, the depressor supercilii, and lack two muscles that are usually differentiated in these mammals, the zygomatico-orbicularis and sphincter colli superficialis. Monkeys such as macaques usually lack two muscles that are often present in strepsirhines, the sphincter colli profundus and mandibulo-auricularis, but have some muscles that are usually absent as distinct structures in non-anthropoid primates, e.g. the levator labii superioris alaeque nasi, levator labii superioris, nasalis, depressor septi nasi, depressor anguli oris and depressor labii inferioris. In turn, macaques typically lack a risorius, auricularis anterior and temporoparietalis, which are found in hominoids such as humans, but have muscles that are usually not differentiated in members of some hominoid taxa, e.g. the platysma cervicale (usually not differentiated in orangutans, panins and humans) and auricularis posterior (usually not differentiated in orangutans). Based on our observations, comparisons and review of the literature, we propose a unifying, coherent nomenclature for the facial muscles of the Mammalia as a whole and provide a list of more than 300 synonyms that have been used in the literature to designate the facial muscles of primates and other mammals. A main advantage of this nomenclature is that it combines, and thus creates a bridge between, those names used by human anatomists and the names often employed in the literature dealing with non-human primates and non-primate mammals.

The forelimbs of 12 genera of New World monkeys, two genera of Old World monkeys, and a gibbon were dissected. Of the 54 muscles examined, 19 exhibited significant intergeneric variation. We present arguments for which morphologies are primitive and which are derived within platyrrhines and within anthropoids. We conclude that the forelimbs of Cebus apella and Callicebus moloch represent good models of the ancestral anthropoid morphology. Thus among living anthropoids they are most appropriate for comparisons with early fossil anthropoids. They are also useful for determining whether myological anomalies of human aneuploids are atavistic. Wagner tree analyses were conducted to assess the value of these myological characters in phylogenetic studies of platyrrhines. In most respects the Wagner trees were consonant with phylogenies previously proposed, although some hypothesized trees are less parsimonious than others in explaining our data. There is an unexpected number of derived features shared by Aotus and the Atelines. There are marked dissimilarities in forelimb musculature between Aotus and Callicebus.

Despite its abundance in Latin America, and its remarkable ability to use tools, there are only a few myological studies on the capuchin monkey, Cebus libidinosus. In the present study, we dissected the forearm extensor muscles of six adult males and two adult females of this species. We describe these muscles and compare them with those of other primates dissected by us and by other authors. The forearm extensor muscles of Cebus monkeys are, in general, more similar to those of other platyrrhines than to distantly related taxa that use tools, such as chimpanzees and modern humans, with three main exceptions: contrary to most other platyrrhines, (1) in Cebus, chimpanzees and modern humans the extensor pollicis longus usually inserts onto Digit I, and not onto Digits I and II; (2) in Cebus the abductor pollicis longus has two separate tendons, as is the case in chimpanzees, and in modern humans (where one of these tendons is associated with a distinct belly, forming the muscle extensor pollicis brevis); (3) in Cebus, and in modern humans and chimpanzees, the extensor pollicis longus is not deeply blended with the extensor indicis. Therefore, the Cebus monkeys provide an illustrative example of how phylogenetic constrains and ecological adaptations have been combined to develop a specific myological configuration that, associated with their sophisticated neurological organization, allow them to easily navigate in their arboreal habitats and, at the same time, to finely manipulate objects in order to search for food and to prepare this food for ingestion. Anat Rec, 293:2056Rec, 293: -2070