Variations of supraorbital bony structures in Sienese skulls

Various non-metrical traits were examined in the supraorbital region in a series of skulls of recorded sex (147 males, 130 females), age (18-80 years) and provenance (Siena and surroundings), using a standard method of categorization and notation introduced by two of the authors in 1983. The results are discussed from a topographic-anatomical point of view in relation to trait variation and with respect to the usefulness of the method applied for population studies.     

Variations in form of the hypoglossal canal

Variation in the nature and extent of division of the hypoglossal canal can be classified by a simple scoring scheme. Applied to three series of crania of differing provenance, the results indicate a continuity in expression of the trait rather than the dichotomous character utilized in previous studies. The similarity in results in these three populations, of widely differing environment, suggests fairly strict canalization of development.     

Fusion patterns of craniofacial sutures in rhesus monkey skulls of known age and sex from Cayo Santiago

Bones of the face and cranial vault meet at sutural boundaries. These sutures are of great importance for craniofacial growth. Although the effects that the sutures have on modulating craniofacial strains have been investigated, how sutural fusion influences primate craniofacial biomechanics and adaptation are less considered. Confounding this problem is the lack of any systematic data on patterns of craniofacial sutural fusion from animals of known age and sex. This study examined the status of 28 sutures in Macaca mulatta skulls from a collection of animals of known age and sex from Cayo Santiago, Puerto Rico. Survival analysis showed that most animals died before all sutures fused. There was high variation in the age at which individual sutures or sutural sections were fused in M. mulatta, and significant differences in the amount of sutural fusion among regions and between males and females. Intensive fusion of sutures took place between ages 5 and 15. Sutures in the facial area tended to be less fused than in the cranial vault. Between adolescence and adulthood, males tended to have more sutural fusion than females, especially in the facial area. These differences might be biomechanical adaptations during ontogeny to craniofacial sexual dimorphism. These findings enrich our understanding of variation in sutural morphology in rhesus monkeys. Comparative information across primate species is essential for understanding the biomechanics of craniofacial form throughout primate evolution.     

Variations in the form of the hypoglossal canal in ancient Anatolian populations: Comparison of two recording methods

In this study, the frequency of bridging of the hypoglossal canal was investigated on 324 skulls belonging to 10 ancient Anatolian populations recovered from various archaeological sites and dated from Early Bronze Age to the first quarter of the 20th century. The change in the frequency of bridging trait in the hypoglossal canal that has already been recorded according to both the traditional method (absent or present) and the graded method (0-5) was analysed here in relationship to age, sex, skull side and population.The results revealed no significant relation between the bridging of hypoglossal canal and age or sex. Both recording methods showed that the studied samples of ancient Anatolian populations exhibited a homogenous structure and they were found to differ considerably from other populations which inhabited lands other than Anatolia. This indicates that these two recording methods produce similar results in comparing populations. The differences between the sides were found to be significant with the detailed recording method as opposed to the dichotomous method. This asymmetry emerging with the detailed recording method is considered to be important in determining the effect of environmental factors upon the trait.     

Sex differences in the Ilia of a known sex and age sample of fetal and infant Skeletons

Ilia from a known sex, race, and age sample of fetal and infant skeletons from the collections of the Smithsonian Institution were evaluated for six metric and one nonmetric characters. Three indices calculated from the measurements were analyzed. The nonmetric trait was examined for fit with known sex. The three indices failed to show significant sex differences. The nonmetric trait, Auricular Surface Elevation, proved dependable (91% accurate) for the male Fetal and Six Month age groups.     

Variations of sodium, potassium, and chloride plasma levels in the rat with age and sex

Sodium, potassium, and chloride plasma levels were measured in 294 male and 286 female Sprague Dawley rats [Crl:COBS CD(SD)BR]. The rats were distributed between four groups according to age (65-125 days, 235-275 days, 353-482 days, and 665-775 days). The levels of all three ions were higher in males than in females: about 1% higher for sodium and chloride and about 7% higher for potassium. Potassium and chloride values decreased with increasing age in both sexes; potassium decreased 12% and chloride decreased 6%. Distributions were not perfectly Gaussian but the departures from normality were slight. It was concluded, therefore, that determinations based on parametric statistical tests on the data are unlikely to be seriously biased by the distribution.     

Serum chemistry profiles for Lechwe waterbucks (Kobus leche): Variations with age and sex

• 1.1. Over an 8-year period, 19 biochemical parameters have been determined at various ages in the blood serum of 92 clinically healthy Lechwe waterbucks (Kobus leche), 33 males and 59 females.
• 2.2. Significant differences have been noted with age. In neonates, the lowest values of total proteins, glucose, creatinine, urea, AST, ALT and iron have been noted; the highest ones have been seen for cholesterol, alkaline phosphatase, calcium and phosphorus.
• 3.3. With regard to sex, raised values of glucose, urea, alkaline phosphatase and ALT, and lowered values of cholesterol, have been noted in juvenile females compared with males of the same age.
• 4.4. In adult females, higher levels of urea and cholesterol and lower levels of glucose, triglycerides and natrium have been recorded compared with males.
• 5.5. With sex and age, no significant changes have been found in the levels of GGT, magnesium, chlorides and copper.
• 6.6. Out findings are discussed with those abstracted from the literature for related species.

     

Accuracy and precision in eel age estimation, using otoliths of known and unknown age

Using otoliths of eels Anguilla anguilla of known and unknown age from fresh, brackish and marine waters, the accuracy of age estimation was uncertain and deviations from the correct age were dependent on reader, locality and fish age.     

Expanding the known diversity and environmental distribution of an uncultured phylogenetic division of bacteria

Culture-independent molecular phylogenetic methods were used to explore the breadth of diversity and environmental distribution of members of the division-level "candidate" phylogenetic group WS6, recently discovered in a contaminated aquifer and with no cultivated representatives. A broad diversity of WS6-affiliated sequences were cloned from 7 of 12 environments investigated: mainly from anaerobic sediment environments. The number of sequences representing the WS6 candidate division was increased from 3 to 60 in this study. The extent of phylogenetic divergence (sequence difference) in this candidate division was found to be among the largest of any known bacterial division. This indicates that organisms representing the WS6 phylogenetic division offer a broad diversity of undiscovered biochemical and metabolic novelty. These results provide a framework for the further study of these evidently important kinds of organisms and tools, the sequences, with which to do so.     

Variations in sexual dimorphism in the skulls of rats subjected to malnutrition, castration, and treatment with gonadal hormones

Two groups of weanling rats were subjected to malnutrition, one with periodic injections of testosterone (males) and the other with estradiol (females). Two other groups (castrated males or castrated females) received normal feedings. In control animals, the relative weights (mg/gm body weight) of testes, seminal vesicles, and ovaries were greater than in malnourished rats. However, relative weights of those organs in hormone-treated, malnourished animals were greater than in those subjected to malnutrition alone and still greater than in controls. Normal sexual cranial dimorphism (SCD) was decreased 16% by male castration, 23% by malnutrition, and 83% by estradiol treatment in malnourished females. On the other hand, normal SCD was increased 20% by female castration and more than 200% by testosterone treatment in malnourished males. All monosexual comparisons corroborated the bisexual range of distances found. Testicular but not ovarian secretions seemed to influence sexual cranial dimorphism. Malnutrition delayed SCD because of a deficiency of testosterone level in stressed males. It is suggested that estradiol in females may counteract sexual cranial development and that its inhibitory effect may be additive to the testosterone deficit evoked by malnutrition.     

Variations in structure of the lateral-line canal on scales of teleostean fishes

Summary Scanning electron microscopy of lateral-line scales of teleostean fishes demonstrates a wide range of structural variation of the lateral-line canal from a simple direct or slightly oblique perforation to an extended canal with or without simple to highly complex cantilevered extensions acting as covers over the anterior canal opening. Possible important implications of these morphological variations in structure of the lateral-line canal in taxonomy, in scale growth and development, and in lateral line mechanoreception are indicated.