Experimental walks with a tame primate reveal that free living primates are likely to be subject to frequent infestation by ticks. Observations on the grooming behavior of mangabeys, red colobus and blue monkeys demonstrated that self grooming is primarily directed to parts of the body not subjected to allo-grooming, and that its role is a cursory brushing away of loose particles rather than a detailed cleansing. Allo-grooming is directed towards the detailed cleansing of the skin and fur, and is associated with frequent particle removal. Length of body fur has a considerable influence on the amount of grooming different parts of the body receive. I suggest that sexual dimorphism, age, sex and dominance status are important in determining rates of ectoparasite acquisition, and so the amount of grooming individuals need and receive.
Orconectes limosus is a primitive species of the genus Orconectes separated geographically from related species occurring in the Mississippi and Cumberland River systems of North America. Investigation of the life history of 0. limosus was undertaken near the northern limit of its distribution along the Atlantic coast. In southern New England, the species copulates any time of the year when active first form males confront females. Egg laying commences in April and lasts to early June, and hatched young appear in June and July. Abdominal egg counts are linearly and positively associated with carapace length. A trend exists where older females commence ovipositing earlier in the season than smaller adult females. Individuals can live up to 3 years but not usually beyond 2 years. Orconectes limosus shows no extraordinary life history when compared with other species of the genus
Masked shrew (Sorex cinereus Kerr) populations in upland hardwood forests of Upper Michigan were studied to determine their breeding status during the dry year of 1976. These populations lacked pregnant adult females and the younger age classes of juveniles. Other age/sex groups were well represented when conditions were moist. Apparently, masked shrews do not breed in upland hardwoods during dry conditions and may entirely abandon uplands during excessively dry periods.
(1981-07) Phillips, Chandler A.; Cox, Terry L.; Petrofsky, Jerrold Scott
The effects of anisotrophy and nonhomogeneity of the ventricular myocardium as represented by a linear increase in the midwall effective modulus of elasticity were investigated in the present study, specifically as they effect the circumferential stress distribution. Various studies are presented suggesting a linear increase in the effective modulus of elasticity from endocardium to epicardium. In our study, this increase in the effective modulus was constrained by the approximation that stress per unit sarcomere length is constant. We evaluated 12 functionally normal cases and 9 functionally abnormal cases. The stress distribution for the 9 functionally abnormal cases was calculated, first with the normal and secondly with the abnormal variation in the modulus of elasticity. Assuming the myocardium has constant material properties that do not change with functional decomposition, the stress distributions in the first calculations indicated higher stresses through the inner half of the myocardium and lower stresses through the outer half of the myocardium as compared to the second. This finding suggests that the inner fibers are overloaded and the outer fibers are underloaded in left ventricular decompensation. The difference between the first and second stress distributions averaged 26% (range: 11% to 48%). A useful, clinical, and quantitative measure of stress loading of the sarcomeres in functionally normal and abnormal left ventricles is proposed.