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Biomedical subjects

C R Taylor

Publications and source records attributed to C R Taylor.

At least 379 records · Page 21Linked to original sources
PubMed1973

Running on two or on four legs: which consumes more energy?

Disagreement exists over whether man's bipedal form of locomotion evolved as an economical means for covering long distances. There is also some disagreement about the energetic price man had to pay to free his hands. In an investigation of the relative energetic cost of bipedal and quadrupedal locomotion in primates, chimpanzees (Pan troglodytes) and capuchin monkeys (Cebus capucinus) were trained to run on a treadmill either on two or on four legs while their oxygen consumption was being measured. Both primates expend the same amount of energy whether running on two or on four legs. The relative energy cost of bipedal versus quadrupedal running should not be used in arguments about the evolution of bipedal locomotion in man.

Animals↗
PubMed1972

Running up and down hills: some consequences of size.

Small mammals are able to run at about the same maximum speed vertically as horizontally, but larger mammals cannot do this. During level running a mouse weighing 30 grams uses about eight times as much energy per unit of body weight as does a chimpanzee weighing 17.5 kilograms (42.6 joules per kilogram meter versus 5.17 joules per kilogram meter). The additional energy required to lift 1 kilogram of body weight 1 meter while running uphill was similar for the two species (about 15.5 joules per kilogram meter). Therefore the increment in energy expenditure for mice to run uphill compared to running horizontally is about one-eighth that for a chimpanzee. Both mice and chimpanzees were able to recover about 90 percent of the energy stored running uphill on the way down.

Animals↗
PubMed1972

Thermal panting in dogs: the lateral nasal gland, a source of water for evaporative cooling.

Two lateral nasal glands appear to provide a large part of the water for evaporative cooling in the panting dog; their function is analogous to that of sweat glands in man. Each gland drains through a single duct which opens about 2 centimeters inside the opening of the nostril. This location may be essential to avoid desiccation of the nasal mucosa during thermal panting. The rate of secretion from one gland increased from 0 to an average of 9.6 g (gland . hour)(-1) as air temperature was increased from 10 degrees to 50 degrees C. Evaporation of the fluid from the paired glands could account for between 19 and 36 percent of the increase in respiratory evaporation associated with thermal panting. The fluid secreted by the gland was hypoosmotic to plasma.

Animals↗
PubMed1970

Panting in dogs: unidirectional air flow over evaporative surfaces.

In dogs which are panting due to a heat load, most of the respired air enters through the nose and leaves through the mouth. Different patterns of flow are, however, possible. The unidirectional flow over the evaporative (nasal) surfaces is an important mechanism for regulating the amount of heat dissipated in panting.

Air↗