Noel Thomas Boaz
Publications
-
1.08Impact points
Structure and functional significance of the transverse vesical fold.
Clinical anatomy (New York, N.Y.). 01/2011; 24(1):62-9.
The plica vesicalis transversa or transverse vesical fold (TVF) is a peritoneal fold extending from the lateral side of the bladder to the side of the lesser pelvis near the deep inguinal ring. It is an important landmark in laparoscopic surgery of the pelvis but is variably observed in the embalmed... [more] The plica vesicalis transversa or transverse vesical fold (TVF) is a peritoneal fold extending from the lateral side of the bladder to the side of the lesser pelvis near the deep inguinal ring. It is an important landmark in laparoscopic surgery of the pelvis but is variably observed in the embalmed cadaver. We investigated the gross anatomy of this structure in the cadaver and confirmed that its medial portion corresponds to the location of the superior vesical artery(ies), thus supporting the idea that the TVF is "mesovesical." However, no large vessels were observed grossly in the lateral portion of the TVF. The hypothesis that the lateral TVF has a suspensory function was tested histologically by comparison with the suspensory ligament of the duodenum and the phrenicocolic ligament, both of which have smooth muscle contributing to their inferred suspensory function. Microscopic examination of prepared samples from 20 cadavers shows that the TVF evinces no smooth muscle in either its lateral or medial segments. The TVF is demonstrated to be a mesentery-like reflection of peritoneum raised by branches of the superior vesical artery which provides no demonstrable structural support for the bladder. Implications of these findings include avoidance of sectioning of medial TVF during laparoscopic surgery because of its vascular nature, and inadvisability of utilizing any portion of theTVF for an anchor in reconstruction of the anterior pelvic floor within the paravesical fossae.
-
2.99Impact points
Mapping and taphonomic analysis of the Homo erectus loci at Locality 1 Zhoukoudian, China.
Journal of human evolution. 06/2004; 46(5):519-49.
From a detailed analysis of published and unpublished sources, we constructed a digitized three-dimensional, stratigraphically-controlled excavation grid of Zhoukoudian Locality 1 in order to assess the spatial relationships of the excavated materials. All 15 fossil Homo erectus loci were mapped on ... [more] From a detailed analysis of published and unpublished sources, we constructed a digitized three-dimensional, stratigraphically-controlled excavation grid of Zhoukoudian Locality 1 in order to assess the spatial relationships of the excavated materials. All 15 fossil Homo erectus loci were mapped on the grid. Meter cubes were used in excavation starting in 1934, and Loci H through O, established between 1934 and 1937, were mapped to within 1 m(3)vertical and horizontal provenience. Loci A through G, established between 1921 and 1933, were excavated in the northernmost part of Locality 1 by unmapped quarrying, but their stratigraphic levels were recorded. We could localize Loci A through G on the grid system by utilizing locations of remaining walls, stratigraphic sections, excavation reports, excavation maps, and photographs. Loci contained skeletal elements of Homo erectus individuals scattered over areas of the cave floor of up to 9 m in diameter. Scoring of taphonomic damage on the Homo erectus sample, as observed on casts and originals, demonstrates that 67% of the hominid sample shows bite marks or other modifications ascribed to large mammalian carnivores, particularly the large Pleistocene cave hyena, Pachycrocuta brevirostris. Virtually all of the remaining Homo erectus skeletal assemblage shows breakage consistent with this taphonomic pattern of fragmentation. Bioturbation by digging carnivores is the most likely explanation for a fragment of Homo erectus Skull XI discovered 1 m below its other conjoined portions in Locus L. Carbon on all the Homo erectus fossils from Locus G, a circumscribed area of 1-meter diameter, earlier taken to indicate burning, cooking, and cannibalism, is here interpreted as detrital carbon deposited under water, perhaps the result of hyaenid caching behavior. Locus G records the close stratigraphic and horizontal association of stone artifacts with Homo erectus and other vertebrate skeletal elements, an association that is seen at other loci as well. Layer 4 of the excavation contains equid cranial bone previously interpreted to have been burned while fresh. We here document that Locus B Homo erectus, including Skull I, is stratigraphically associated with this evidence, but at some 10-12 m distance. Even though the presence of wood-stoked fires and hearths is not supported by geochemical results, evidence of fire at Locality 1 in the form of burned bone is confirmed. Contextual relationships of fossil skeletal elements, relationships of carnivore damage and stone tool cutmarks on bone, and evidence of the burning of fresh bone associated with Homo erectus and stone tools support a model of transient hominid scavenging aided by the use of fire at the large hyenid den that became Zhoukoudian Locality 1. Although the original excavation catalogue from Locality 1, as well as a significant number of fossils and stone artifacts, were lost during World War II, catalogue numbers on the many surviving specimens can be used to locate fossils and artifacts within the three-dimensional grid provided in this paper.
-
2.32Impact points
Paleoclimatic setting for Homo sapiens neanderthalensis.
Die Naturwissenschaften. 02/1982; 69(1):29-33.
A paleoclimatic hypothesis is presented to account for the evolution and eventual replacement of Homo sapiens neanderthalensis. Neandertal populations in the European Late Pleistocene were largely isolated by geographic barriers. Populations of modern Homo sapiens replaced Neandertals at 34000 years... [more] A paleoclimatic hypothesis is presented to account for the evolution and eventual replacement of Homo sapiens neanderthalensis. Neandertal populations in the European Late Pleistocene were largely isolated by geographic barriers. Populations of modern Homo sapiens replaced Neandertals at 34000 years ago, near the end of the relatively cold oxygen isotope stage 3. These population were pushed into Europe by conditions brought on by increasing aridity affecting North Africa and southwestern Asia, and their dispersal was facilitated by lowered sea level.
-
34.48Impact points
Tempo and mode in hominid evolution.
Nature. 08/1981; 292(5819):113-22.
The nature of human evolution has been viewed recently as a specific example of a more general model of evolution termed "punctuated equilibrium". The characteristics of this model are long periods of little or not evolutionary change (stasis) interspersed with periods of rapid (punctuated... [more] The nature of human evolution has been viewed recently as a specific example of a more general model of evolution termed "punctuated equilibrium". The characteristics of this model are long periods of little or not evolutionary change (stasis) interspersed with periods of rapid (punctuated) morphological change. Careful analysis of the hominid fossil record over the past 4.0 million years, however, suggests no well documented examples of either stasis or punctuation. The evidence for the evolution of the hominid lineage is most reasonably interpreted by a model of more gradual change with periods of varying rates of evolution.
-
2.76Impact points
A hominoid clavicle from the Mio-Pliocene of Sahabi, Libya.
American journal of physical anthropology. 08/1980; 53(1):49-54.
The first definitive hominoid from the Libyan Mio-Pliocene site of Sahabi is described. The specimen is a left clavicle, lacking a portion of the acromial end. In superior view it shows a marked sternal curvature, similar to homonids, but it also shows a curvature in the coronal plane, similar to th... [more] The first definitive hominoid from the Libyan Mio-Pliocene site of Sahabi is described. The specimen is a left clavicle, lacking a portion of the acromial end. In superior view it shows a marked sternal curvature, similar to homonids, but it also shows a curvature in the coronal plane, similar to the pongid condition. Muscle attachments for sternocleidomastoid, pectoralis major and the anterior portion of deltoid are preserved. The robust attachment for the latter suggests relative hypertrophy of this muscle. These considerations and certain morphological similarities to hominids do not suggest a functional reconstruction of locomotor behavior similar to Miocene dryopithecines. Nevertheless, more complete functional and taxonomic discussions must await further work at Sahabi.
-
29.75Impact points
Early Hominid Population Densities: New Estimates.
Science (New York, N.Y.). 12/1979; 206(4418):592-595.
Proportional faunal representations in excavated fossil occurrences (Shungura Formation, Omo, Ethiopia) are very similar to modern sub-Saharan mammalian faunal proportions in a variety of environments. Early hominids comprise between 0.6 and 1.6 percent of the excavated assemblage, corrected to refl... [more] Proportional faunal representations in excavated fossil occurrences (Shungura Formation, Omo, Ethiopia) are very similar to modern sub-Saharan mammalian faunal proportions in a variety of environments. Early hominids comprise between 0.6 and 1.6 percent of the excavated assemblage, corrected to reflect numbers of individuals. With allochthonous faunal localities for comparison, direct analogies to modern fauna suggest early hominid population densities of between 0.006 to 1.7 individuals per square kilometer. Calculations based on population densities of modern large mammals indicate that population densities of early hominids were between 0.001 and 2.48 individuals per square kilometer.
-
29.75Impact points
Stratigraphic Interpretation of the Omo Shungura and Lake Turkana Fossil Suid Record.
Science (New York, N.Y.). 01/1979; 202(4374):1309.
-
2.76Impact points
A gracile hominid cranium from upper member G of the Shungura formation, Ethiopia.
American journal of physical anthropology. 02/1977; 46(1):93-108.
A fragmentary hominid cranium with teeth, specimen L.894-1, dating from 1.84 m.y. BP in the Shungura Formation at Omo, is described. From its dental and cranial morphology and because of similarities to Olduvai Hominids 24 and 13 and Sangiran 4, among others, it is concluded that the specimen repres... [more] A fragmentary hominid cranium with teeth, specimen L.894-1, dating from 1.84 m.y. BP in the Shungura Formation at Omo, is described. From its dental and cranial morphology and because of similarities to Olduvai Hominids 24 and 13 and Sangiran 4, among others, it is concluded that the specimen represents a member of an early species of the genus Homo (Homo habilis or Homo modjokertensis). The specimen shows approximal grooving on the premolars, pre-mortem chipping of the molar enamel, foramina ovale and spinosum divided by the sphenosquamosal suture, limited pneumatization of the mastoid region, and a possible interparietal bone. Sedimentological, ostracod, pollen, macrofloral, and taphonomic data indicate that the paleo-environmental context was a savanna/grassland or savanna woodland on the margin of a saline lake.
-
2.76Impact points
Hominid taphonomy: transport of human skeletal parts in an artificial fluviatile environment.
American journal of physical anthropology. 08/1976; 45(1):53-60.
Flume experiments demonstrate that human skeletal parts sort into lag and transportable groups in a current flow of 31 cm/sec. Orientations, rates and types of movement, and stable positions are recorded. Density of a skeletal part is correlated with the average rate of movement, whereas wet weight ... [more] Flume experiments demonstrate that human skeletal parts sort into lag and transportable groups in a current flow of 31 cm/sec. Orientations, rates and types of movement, and stable positions are recorded. Density of a skeletal part is correlated with the average rate of movement, whereas wet weight in air, weight in water, and volume are not. Shape is an important but unquantifiable factor. Complete crania are the fastest moving elements; individual cranial fragments are in the lag group. Omo fluviatile deposits show a preponderance of hominid lag elements, whereas Olduvai and East Rudolf perilacustrine deposits present a mixture of transportable and lag elements.
-
Paleoecology of Plio-Pleistocene Hominidae in the Lower Omo Basin, Ethiopia /
Thesis (Ph. D.)--University of California, Berkeley, 1977. Includes bibliographical references (leaves 156-190). Photocopy.
-
Mapping and taphonomic analysis of the Homo erectus loci at Locality 1 Zhoukoudian, China
Journal of Human Evolution.
From a detailed analysis of published and unpublished sources, we constructed a digitized three-dimensional, stratigraphically-controlled excavation grid of Zhoukoudian Locality 1 in order to assess the spatial relationships of the excavated materials. All 15 fossil Homo erectus loci were mapped on ... [more] From a detailed analysis of published and unpublished sources, we constructed a digitized three-dimensional, stratigraphically-controlled excavation grid of Zhoukoudian Locality 1 in order to assess the spatial relationships of the excavated materials. All 15 fossil Homo erectus loci were mapped on the grid. Meter cubes were used in excavation starting in 1934, and Loci H through O, established between 1934 and 1937, were mapped to within 1 m3vertical and horizontal provenience. Loci A through G, established between 1921 and 1933, were excavated in the northernmost part of Locality 1 by unmapped quarrying, but their stratigraphic levels were recorded. We could localize Loci A through G on the grid system by utilizing locations of remaining walls, stratigraphic sections, excavation reports, excavation maps, and photographs. Loci contained skeletal elements of Homo erectus individuals scattered over areas of the cave floor of up to 9 m in diameter. Scoring of taphonomic damage on the Homo erectus sample, as observed on casts and originals, demonstrates that 67% of the hominid sample shows bite marks or other modifications ascribed to large mammalian carnivores, particularly the large Pleistocene cave hyena, Pachycrocuta brevirostris. Virtually all of the remaining Homo erectus skeletal assemblage shows breakage consistent with this taphonomic pattern of fragmentation. Bioturbation by digging carnivores is the most likely explanation for a fragment of Homo erectus Skull XI discovered 1 m below its other conjoined portions in Locus L. Carbon on all the Homo erectus fossils from Locus G, a circumscribed area of 1-meter diameter, earlier taken to indicate burning, cooking, and cannibalism, is here interpreted as detrital carbon deposited under water, perhaps the result of hyaenid caching behavior. Locus G records the close stratigraphic and horizontal association of stone artifacts with Homo erectus and other vertebrate skeletal elements, an association that is seen at other loci as well. Layer 4 of the excavation contains equid cranial bone previously interpreted to have been burned while fresh. We here document that Locus B Homo erectus, including Skull I, is stratigraphically associated with this evidence, but at some 10–12 m distance. Even though the presence of wood-stoked fires and hearths is not supported by geochemical results, evidence of fire at Locality 1 in the form of burned bone is confirmed. Contextual relationships of fossil skeletal elements, relationships of carnivore damage and stone tool cutmarks on bone, and evidence of the burning of fresh bone associated with Homo erectus and stone tools support a model of transient hominid scavenging aided by the use of fire at the large hyenid den that became Zhoukoudian Locality 1. Although the original excavation catalogue from Locality 1, as well as a significant number of fossils and stone artifacts, were lost during World War II, catalogue numbers on the many surviving specimens can be used to locate fossils and artifacts within the three-dimensional grid provided in this paper.
-
Paleoecology of Plio-Pleistocene Hominidae in the Lower Omo Basin, Ethiopia [microform] /
Thesis--University of California, Berkeley. Includes bibliographical references (leaves 156-190). Microfilm of typescript.
