Wind-induced ventilation of the burrow of the prairie-dog,Cynomys ludovicianus
- 574 Downloads
Where a fluid flows across a surface, such as wind over the earth, the velocity gradient created provides a potential source of work. This gradient might be employed by one burrowing animal to induce air-flow in its long, narrow burrow. The burrow of the black-tailed prairie-dog constitutes a respiratory dead-space of extraordinary magnitude in which diffusion appears inadequate for gas exchange. But the burrow is arranged in a manner appropriate for wind-induced ventilation, typically with two openings at opposite ends and with mounds surrounding these openings of two forms (Fig. 3), with one form on each end.
When a breeze crosses the mounds, air enters the burrow through the lower mound and leaves through the higher. The same unidirectional flow is evident with scale models of real mounds on a model burrow in a wind tunnel; flow inside the burrow is nearly a linear function of flow across the mounds (Fig. 4). Wind-induced ventilation in the model burrow could also be induced with model mounds differing in shape but not height. Mounds with sharp rims were more effective exits for air than mounds with rounded tops; in nature such shape differences complement the differences in height.
KeywordsWind Tunnel Burrow Entrance Mound Height Cynomys Ludovicianus Burrow Length
Unable to display preview. Download preview PDF.
- Balsam, W. L., Vogel, S.: Water movement in archaeocyathids: Evidence and implications of passive flow in models. J. Paleont., (in press, 1973).Google Scholar
- Geiger, R.: The climate near the ground. Cambridge: Harvard University Press 1965.Google Scholar
- Jacobs, M. H.: Diffusion processes. Berlin-Heidelberg-New York: Springer 1967.Google Scholar
- King, J, A.: Social behavior, social organization, and population dynamics in a black-tailed prairiedog town in the Black Hills of South Dakota. Contr. Lab. vertebr. Biol. Univ. Mich. No.67, 1–123 (1955).Google Scholar
- Kleiber, M.: The fire of life, 2nd ed. New York: John Wiley & Sons, Inc. 1961.Google Scholar
- Merriam, C. H.: The prairie dog of the Great Plains. Yb. U. S. Dep. Agric. p. 257–270 (1901).Google Scholar
- Olszewski, J. L., Skoczen, S.: The airing of burrows of the mole. Acta theriol.10, 181–193 (1965).Google Scholar
- Prandtl, L., Tietjens, O. G.: Applied hydro- and aeromechanics. New York: Dover Publications 1934.Google Scholar
- Sattler, W.: Über den Körperbau, die Ökologie und Ethologie der Larve und Puppe vonMacronema Pict. (Hydropsyohidae). Arch. Hydrobiol.69, 26–60 (1963).Google Scholar
- Scheffer, T. H.: Ecological comparisons of the plains prairie-dog and the zuni species. Trans. Kans. Acad. Sci.49, 401–406 (1947).Google Scholar
- Schmidt-Neilsen, K.: Desert animals Oxford: Clarendon Press 1964.Google Scholar
- Tucker, V. A., Parrott, G. C.: Aerodynamics of gliding flight in a falcon and other birds. J. exp. Biol.52, 345–367 (1970).Google Scholar
- Vogel, S.: Low speed wind tunnels for biological investigations, p. 295–325. In: Experiments in physiology and biochemistry, vol. 2, G. A. Kerkut, Ed. London: Academic Press 1969.Google Scholar