Results 91 to 100 of about 29,197 (258)
The fossil record stays silent: Confusions and conundrums for hominin pelvis evolution
The Anatomical Record, EarlyView.Abstract The evolution of the hominin pelvis is commonly modeled as a series of stages driven largely by the requirements of bipedal locomotion, reproduction, thermoregulation, and pelvic floor muscular support. These patterns are complicated by variation in canal dimensions in relationship with different changes in overall pelvic breadths. To quantify
Helen K. Kurki, Cara M. Wall‐Scheffler
wiley +1 more source
DiversityCyclophorus ateribalteiformis is a dioecious land snail species endemic to China. In a recent field survey in Xishuangbanna, Yunnan Province, we observed shell color dimorphism in this species, with a pale-yellow shell morph found only in males ...
Guang-Long Xie +4 more
doaj +1 more source
The mechanism of labor in nonhuman primates: A look inside
The Anatomical Record, EarlyView.Abstract While in humans, the flexed position of the fetus and its rotating course down the birth canal are well documented, in other primates the mechanism of labor is unknown. Despite the lack of comparative data, it is commonly assumed that the human obstetric mechanism is unique, and anthropologists have disputed when and why the transition to the ...
Melissa K. Stoller
wiley +1 more source
Scientific ReportsThe persistence of color polymorphism in nature may be driven by disassortative mating based on color. In vertebrates, body size sometimes correlates with coloration, complicating mating patterns, as the selective pressures favoring mixed-color pairs ...
Deseada Parejo +3 more
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The Anatomical Record, EarlyView.Abstract The cortical bone structure of long bone diaphyses changes throughout growth via skeletal modeling and has important implications for bone strength and structural integrity. Ontogenetic trends in diaphyseal structure have been identified in both chimpanzees and humans but it is not yet clear how these trends compare given notable differences ...
Karen R. Swan +3 more
wiley +1 more source
The Anatomical Record, EarlyView.Abstract Cortical bone expansion is an age‐related process where, through endosteal resorption and periosteal apposition, cross‐sectional diameter increases while cortical thickness decreases in long bone diaphyses. Local variation has been observed in this process between cross‐sectional locations, but few studies have examined directional variation ...
Gregory J. Wehrman +4 more
wiley +1 more source
Postnatal craniomandibular growth in Harbor seals (Phoca vitulina vitulina)
The Anatomical Record, EarlyView.Postnatal ontogeny in Harbor seals (Phoca vitulina vitulina). Cranium and mandible grow rapidly until 5 years of age, followed by a deceleration and finally a stagnation. Abstract As secondarily aquatic carnivores, seals display several phenotypic differences compared to their terrestrial relatives.
Elisabeth Steinbach +2 more
wiley +1 more source
Evaluating Bergmann's and Allen's rules in the long bones of the eastern gray squirrel
The Anatomical Record, EarlyView.Abstract Ecogeographical rules predict variation in body size and appendage proportions across climatic gradients, yet intraspecific tests using long bones from wild populations remain limited among small mammals. This study tests the hypothesis that eastern gray squirrels (Sciurus carolinensis) conform to Bergmann's rule, that is, body size increases ...
Tyler Blake, Habiba Chirchir
wiley +1 more source
Size dimorphism in six juliform millipedes [PDF]
Arthropods, 2019 Sexual Size Dimorphism (SSD) in the diplopod genera Bicoxidens, Doratogonus, Harpagophora, Julomorpha and Orthoporoides has length, width and rings as the main components of interspecific variation. Interspecific variation in size observed in B.
Mark Cooper
doaj
The Anatomical Record, EarlyView.Abstract The obstetrical dilemma hypothesis (ODH) proposes an evolutionary trade‐off between obstetric requirements and locomotor performance. However, whether external pelvic breadth measures influence walking energetics during human growth remains poorly understood.
Guillermo Zorrilla‐Revilla +4 more
wiley +1 more source