Journal of Comparative Physiology B

, Volume 173, Issue 4, pp 347–353 | Cite as

Metabolism and thermoregulation in the springhare (Pedetes capensis)

Original Paper

Abstract

Springhares are large, nocturnally active, diurnally fossorial rodents that typically inhabit arid and semi-arid areas. This lifestyle means that they need to balance excessive heat loss when foraging at night against insufficient heat loss in a potentially warm, humid burrow and both of these against the need to minimize water turnover and energy requirements. In this study we investigated metabolism and thermoregulation in these animals. Basal metabolic rate averaged 8.62±1.37 J g−1 h−1 and minimum thermal conductance 0.386±0.062 J g−1 h−1 °C−1. These were higher and lower than expected, respectively. This, along with a relatively low, lower critical temperature and broad thermal neutral zone indicate that springhares are physiologically well suited to the low night-time temperatures, which they typically encounter. Body temperatures were quite labile but springhares became hyperthermic at temperatures above 30 °C suggesting that they are poor thermoregulators at high temperatures. This is attributed to their seldom, if ever, encountering temperatures in this range. Insufficient heat loss under normal resting conditions does not appear to be a problem, as springhares inhabit deep burrows in which the temperature never exceeds the upper critical temperature. Excess heat generated during vigorous underground exercise is presumably stored and dissipated to the cool night air or the cooler soil when subsequently resting. Water turnover and energy expenditure are presumably adequately addressed by other physiological and behavioural characteristics.

Keywords

Springhares Metabolism Thermoregulation Burrow microclimate 

Abbreviations

BMR

basal metabolic rate

C

wet thermal conductance

STPD

standard temperature and pressure of dry air

Ta

ambient (chamber) temperature

Tb

body temperature

TNZ

thermal neutral zone

References

  1. Anderson PC (1996) The population dynamics and ecological role of the springhare Pedetes capensis (Forster, 1778) in the Kimberley area, Northern Cape Province, South Africa. PhD Thesis. University of the Orange Free StateGoogle Scholar
  2. Baudinette RV (1972) Energy metabolism and evaporative water loss in the California ground squirrel. J Comp Physiol 81:57–72Google Scholar
  3. Borut A, Shkolnik A (1974) Physiological adaptations to the desert environment. In: Robertshaw D (ed) MTP international review of science, physiology. Series 1. Environmental physiology. Butterworth, London, pp 185–229Google Scholar
  4. Bradley SR, Deavers DR (1980) A re-examination of the relationship between thermal conductance and body weight in mammals. Comp Biochem Physiol A 65:465–476CrossRefGoogle Scholar
  5. Butynski TM (1984) Nocturnal ecology of the springhare, Pedetes capensis, in Botswana. Afr J Ecol 22:7–22Google Scholar
  6. Butynski TM, Mattingly R (1979) Burrow structure and fossorial ecology of the springhare Pedetes capensis in Botswana. Afr J Ecol 17:205–215Google Scholar
  7. Degen AA (1997) Ecophysiology of small desert mammals. Springer, Berlin Heidelberg New YorkGoogle Scholar
  8. Downs CT, Perrin MR (1990) Thermal parameters of four species of Gerbillurus. J Thermal Biol 15:291–300CrossRefGoogle Scholar
  9. Gettinger RD (1975) Metabolism and thermoregulation of a fossorial rodent, the northern pocket gopher (Thomomys talpoides). Physiol Zool 48:311–322Google Scholar
  10. Gettinger RD (1984) Energy and water metabolism of free-ranging pocket gophers, Thomomys bottae. Ecology 65:740–751Google Scholar
  11. Glenn ME (1970) Water relations in three species of deer mice (Peromyscus). Comp Biochem Physiol A 33:231–248CrossRefGoogle Scholar
  12. Goyal SP, Ghosh PK (1983) Body weight exponents of metabolic rate and minimal thermal conductance in burrowing desert rodents. J Arid Environ 6:43–52Google Scholar
  13. Hainsworth FR (1967) Saliva spreading, activity, and body temperature regulation in the rat. Am J Physiol 212:1288–1292PubMedGoogle Scholar
  14. Hart JS (1971) Rodents. In: Whittow GC (ed) Comparative physiology of thermoregulation, vol. II. Academic Press, New York, pp 1–149Google Scholar
  15. Hayssen V, Lacy RC (1985) Basal metabolic rates in mammals: taxonomic differences in the allometry of BMR and body mass. Comp Biochem Physiol A 81:741–754PubMedGoogle Scholar
  16. Hinds DS, MacMillen RE (1985) Scaling of energy metabolism and aerobic capacity in heteromyid rodents. Physiol Zool 58:282–298Google Scholar
  17. Hudson JW (1962) The role of water in the biology of the antelope ground squirrel, Citellus leucurus. University of California Publications 64:1–56Google Scholar
  18. Kronfeld N, Shkolnik A (1996) Adaptations to life in the desert in the brown hare (Lepus capensis). J Mammal 77:171–178Google Scholar
  19. Levy A (1964) The accuracy of the bubble method for gas flow measurements. Sci Instrument 41:449–453CrossRefGoogle Scholar
  20. Lovegrove BG (1986) Thermoregulation of the subterranean rodent genus Bathyergus (Bathyergidae). S Afr J Zool 21:283–288Google Scholar
  21. Lovegrove BG (1987) Thermoregulation in the subterranean rodent Georychus capensis (Rodentia: Bathyergidae). Physiol Zool 60:174–180Google Scholar
  22. Lovegrove BG (2000) The zoogeography of mammalian basal metabolic rate. Am Nat 156:201–219PubMedGoogle Scholar
  23. MacMillen RE (1965) Aestivation in the cactus mouse, Peromyscus eremicus. Comp Biochem Physiol A 16:227–248CrossRefGoogle Scholar
  24. MacMillen RE (1972) Water economy of nocturnal desert rodents. Symp Zool Soc Lond 31:147–174Google Scholar
  25. MacMillen RE, Lee AK (1970) Energy metabolism and pulmocutaneous water loss of Australian hopping mice. Comp Biochem Physiol 35:355–369CrossRefGoogle Scholar
  26. Matthee CA, Robinson TJ (1997) Mitochondrial DNA phylogeography and comparative cytogenetics of the springhare, Pedetes capensis (Mammalia: Rodentia). J Mammal Evol 4:53–73Google Scholar
  27. McNab BK (1966) The metabolism of fossorial rodents: a study of convergence. Ecology 47:712–733Google Scholar
  28. McNab BK (1970) Body weight and the energetics of temperature regulation. J Exp Biol 53:329–348PubMedGoogle Scholar
  29. McNab BK (1979a) Climatic adaptation in the energetics of heteromyid rodents. Comp Biochem Physiol A 62:813–820CrossRefGoogle Scholar
  30. McNab BK (1979b) The influence of body size on the energetics and distribution of fossorial and burrowing animals. Ecology 60:1010–1021Google Scholar
  31. McNab BK (1980) On estimating thermal conductance in endotherms. Physiol Zool 53:145–156Google Scholar
  32. McNab BK, Morrison PR (1963) Body temperature and metabolism in subspecies of Peromyscus from arid and mesic environments. Ecol Monogr 33:63–82Google Scholar
  33. Müller EF, Kamau JMZ, Maloiy GMO (1979) O2-Uptake, thermoregulation and heart rate in the springhare (Pedetes capensis). J Comp Physiol B 133:187–191Google Scholar
  34. Murie M (1961) Metabolic characteristics of mountain, desert and coastal populations of Peromyscus. Ecology 42:723–740Google Scholar
  35. Neal CM, Lustick SI (1973) Energetics and evaporative water loss in the short-tailed shrew Blarina brevicauda. Physiol Zool 46:180–185Google Scholar
  36. Needham AD, Dawson TJ, Hales JRS (1974) Forelimb blood flow and saliva spreading in the thermoregulation of the red kangaroo, Megaleia rufa. Comp Biochem Physiol A 49:555–565CrossRefPubMedGoogle Scholar
  37. Peinke DM (2000) The ecology and physiology of the springhare (Pedetes capensis) in the Eastern Cape Province of South Africa. PhD Thesis. Rhodes University, GrahamstownGoogle Scholar
  38. Peinke DM, Brown CR (1999) Osmoregulation and water balance in the springhare Pedetes capensis. J Comp Physiol B 169:1–10CrossRefPubMedGoogle Scholar
  39. Prakash I, Ghosh PK (1975) Rodents in desert environments. Junk, The HagueGoogle Scholar
  40. Reinking LN, Kilgore DL, Fairbanks ES, Hamilton JD (1977) Temperature regulation in normothermic black-tailed prairie dogs, Cynomys ludovicianus. Comp Biochem Physiol A 57:161–165CrossRefGoogle Scholar
  41. Schmidt-Nielsen K (1964) Desert animals: physiological problems of heat and water. Oxford University Press, LondonGoogle Scholar
  42. Schmidt-Nielsen K (1990) Animal physiology: adaptation and environment. Cambridge University Press, CambridgeGoogle Scholar
  43. Schmidt-Nielsen K, Schmidt-Nielsen B, Jarnum SA, Houpt TR (1957) Body temperature of the camel and its relation to water economy. Amer J Physiol 188:103–112Google Scholar
  44. Schulze BR (1947) The climates of South Africa according to the classifications of Köppen and Thornthwaite. S Afr Geogr J 29:32–42Google Scholar
  45. Schulze BR (1986) Climate of South Africa. Part 8. General survey. Weather Bureau, Department of Environmental Affairs, PretoriaGoogle Scholar
  46. Skinner JD, Smithers RHN (1990) The mammals of the southern African subregion. University of Pretoria, PretoriaGoogle Scholar
  47. Smithers RHN (1971) The mammals of Botswana. National Museums and Monuments of Rhodesia, Museum Memoir No. 4. Mardon Printers, SalisburyGoogle Scholar
  48. Taylor CR, Sale JB (1969) Temperature regulation in the hyrax. Comp Biochem Physiol 31:903–907CrossRefGoogle Scholar
  49. Thompson BW (1967) Climate. In: Morgan WTW (ed) Nairobi: City and Region. Oxford University Press, London, pp 20–38Google Scholar
  50. Wunder BA (1970) Temperature regulation and the effects of water restriction on Merriam's chipmunk, Eutamias merriami. Comp Biochem Physiol 33:385–403PubMedGoogle Scholar

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Gauteng Department of Agriculture, Conservation, Environment and Land AffairsJohannesburg 2000South Africa
  2. 2.Department of Zoology and EntomologyRhodes UniversityGrahamstown 6140South Africa
  3. 3.Gauteng Department of Agriculture, Conservation, Environment and Land AffairsJohannesburg 2000South Africa
  4. 4.Hartpury CollegeUniversity of the West of EnglandHartpury GL19 3BEEngland

Personalised recommendations