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Most recent phylogenetic analyses of snakes have recognized two major clades within Serpentes: Alethinophidia and Scolecophidia. Alethinophidians feed predominantly on relatively large vertebrate prey, which they transport into and through the mouth via reciprocating ratcheting movements of the toothed palatopterygoid jaw arches. In contrast, scolecophidians are small-prey specialists, feeding almost exclusively on small arthropods. In addition, these diminutive, fossorial snakes lack many of the key morphological features which underlie the feeding mechanisms of alethinophidians, such as toothed palatopterygoid jaw arches and a distensible lower jaw. However, the functional significance of these morphological differences has remained poorly understood because there have been no detailed descriptions of feeding behavior in Scolecophidia. I used magnified high-speed videography, videofluoroscopy, and standard histological and gross morphological preparations to study the functional morphology of the feeding apparatus in representatives of two families of Scolecophidia, Leptotyphlopidae and Typhlopidae. In Leptotyphlops (Leptotyphlopidae), a mandibular raking mechanism is used to capture, ingest and transport prey. In this mechanism, the toothed anterior portions of the mandibular rami are rotated medially about the intramandibular joints in a bilaterally synchronous fashion. In contrast, Typhlops and Rhinotyphlops (Typhlopidae) feed via a maxillary raking mechanism, in which asynchronous rotations of the toothed maxillae are used to drag prey into and through the mouth. Both mandibular raking and maxillary raking involve exceptionally rapid (3–5 Hz) movements of the tooth-bearing elements of the jaws, thereby facilitating the ingestion of large numbers of small prey within relatively brief periods of time.

Canids have long been considered to be conservative in their postcranial anatomy, so there are few studies examining individual canid taxa for locomotor adaptations. Canids are generally considered to be the most cursorial of the carnivorans. The limbs of large canids are generally adapted for rapid terrestrial locomotion, as these animals frequently rely on speed for prey capture. The prey animal is captured and killed using the jaws and teeth. Smaller canids, such as the red fox Vulpes and gray fox Urocyon, do not use their limbs primarily for fast running. The red fox appears to have many adaptations for running, including long slender legs, but these foxes do not run in their daily activities except when chased. The red fox uses its forelimbs to help in prey capture and its hind legs for leaping. The gray fox is an unusual canid since it regularly climbs trees. The limbs of the gray fox, especially the forelimb, are utilized in climbing. This dissertation contains a detailed description of the postcranial osteology and myology Vulpes and Urocyon cinercoargenteus and includes an analysis of these anatomical features in a functional framework. An examination of both the osteology and myology of the fore and hind limbs of these two foxes reveals that their behavior is reflected in a number of anatomical characters. Adaptations for leaping in the red fox include the presence of unusually long hind legs relative to the front legs, and an increase in the length of the distal bony limb elements relative to more proximal ones. In addition, the limb bones are very slender. Muscle bellies of tarsal and digital flexors and extensors are restricted to a proximal position on the limb, and muscles in general are emphasized that act along the long axis of the limbs. Adaptations of the gray fox for climbing include the presence of relatively short legs, a greater ability to rotate the radius on the ulna relative to other canids, and a relatively greater ability to abduct the hind limb. In addition, both red and gray foxes are able to retract their claws, an ability that is not generally associated with canids.

Most larval and permanently aquatic salamanders use undulatory swimming as their primary mode of steady aquatic locomotion. These swimming movements are powered by the segmented axial musculature. The hypaxial region of each segment consists of distinct muscle layers, which have a simple planar geometry and have varying architectural features. In an aquatic salamander Siren lacertina, the morphological features of the lateral hypaxial layers allow the shortening of muscle fibers to be amplified during contraction. The angled muscle fibers in these layers function to allow fiber shortening to be accompanied by substantial rotation of muscle fibers during contraction. The connective tissue sheets separating adjacent muscle segments (myosepta), allow the segment to bulge in a way that further amplifies muscle fiber rotation. The combined effect of architectural and moment arm variation ensures that muscle fibers from different layers undergo similar shortening patterns during swimming to allow for the generation of optimal tension during locomotion. In addition to steady swimming many salamanders respond to a predatory stimulus by performing a “C-start” aquatic escape response. This unsteady maneuver involves two kinematic stages, which function to propel the salamander away from the perceived threat. During metamorphosis, the tailfin of salamanders is resorbed and is thought to result in a substantial decrease in escape performance. However, in a stream salamander Eurycea bislineata , adults spend significant time in the water and behaviorally compensate for metamorphic changes in tail morphology by increasing the amplitude of escape responses. Aquatic locomotion in salamanders is not limited to axial swimming. Some salamanders also utilize their limbs to move along the substrate at slow speeds, while submerged. Structures used during aquatic walking face dramatically different mechanical loads compared to limbs used on land. The greater hydrodynamic resistance associated with water lowers the effective weight and can act to stabilize an organism throughout its gait. Therefore structures, such as the reduced limbs of S. lacertina, which would be considered ineffective on land, can be fully functional during aquatic walking.

Immunocytochemistry was used to study the distribution of gamma-aminobutyric acid (GABA) throughout the central visual nuclei and retina in Rana pipiens. In the diencephalon, intensely-labeled GABA immunoreactive neurons and nerve fibers were observed within the neuropil of Bellonci (nB) and corpus geniculatum (CG), while only immunoreactive puncta were found in the rostral visual nucleus (RVN). In the pretectal region, the posterior thalamic nucleus (nPT) contained the most intensely-labeled GABA immunoreactive perikarya and nerve fibers in the entire brain. Lightly immunoreactive perikarya were also found in the large-celled nucleus lentiformis mesencephali (nLM), as well as in the pretectal gray which contains neurons postsynaptic to the retinal terminal zones within nLM. In the optic tectum (OT), both immunoreactive perikarya and fibers were found within superficial layers 8 and 9; whereas only densely-packed immunoreactive perikarya were evident in the deep tectal layers (i.e. 2, 4, 6). The nucleus of the basal optic root (nBOR) contained a small number of lightly-labeled GABA immunoreactive perikarya mostly located in the dorsal half of the nucleus. A large number of perikarya within the nucleus isthmi (NI) were also lightly immunostained. In the retina, GABA immunoreactivity (both somata and fibers) was observed in all layers except the outer nuclear layer (ONL). Besides GABAergic putative horizontal and amacrine cells in the inner nuclear layer (INL), about 30% of total neurons within ganglion cell layer (GCL) expressed GABA immunoreactivity. Double-labeling studies indicated that about half of the GABA-containing perikarya in the GCL were retinal ganglion cells (RGCs). In addition, three GABAergic projection pathways existing in the visual system of Rana pipiens were demonstrated: (1) from RGCs to the contralateral OT; (2) from nBOR to the pretectal nLM; and (3) bilaterally from the NI to the OT. These results indicate that GABA is an important neurotransmitter in the frog visual system.

With the progression of multivariate statistics, the creation of population specific equations is on the rise. Multivariate analysis generally revolves around metric methods or geometric morphometrics, not on morphoscopic features. A total of eight samples were analysed spanning from prehistoric American to modern day South African and ranged between pygmy populations from the Andaman Islands to medieval British populations. With a sample size of more than 1100 individuals, each os coxa was scored using eight morphoscopic features most commonly used by physical anthropologists and osteoarchaeologists. Trait frequencies were compiled and compared between each of the eight samples. Then, the samples were placed into two groups: a known age and sex group (Christ Church Spitalfields, South African White, South African Black, and South African Coloured), and an unknown archaeological group (Poulton, St. Owens, Chumash, and Andaman). When comparing trait frequencies, slight differences between the samples could be seen. Ordinal Logistic Regressions (OLR) were applied onto each of the four samples from the known age and sex group to create population specific sexing equations (cross-validated). Results from these four equations ranged from 90.24% (South African Black population specific equation) to 96.38% (Christ Church, Spitalfields population specific equation). Population specifity was tested by applying all of the equations onto each sample in this group. In an attempt to reduce this, two new equations were created by combining samples together resulting in a South African specific equation (92.54% accuracy) and a "Summary Sex" equation (92.98% accuracy). After applying each of the six new OLR equations onto the four archaeological samples, high percentage accuracies (ranging from 92.59% to 100.00%) were found when comparing them to the previous records. The only sample that did not produce as high of an accuracy was the Chumash sample with 82.35%. In the attempt to analyse fragmented remains, three avenues were taken. Firstly, all missing values were replaced by the median score. Secondly, the original six OLR equations were 'sectioned' to make three smaller sets of equations. Lastly, to mirror the sectioned equations, three new sets of OLR equations were generated. This study shows that when using morphoscopic traits for sex estimation, applying multivariate techniques can be used to obtain a high accuracy even when dealing with fragmented samples.