Advertisement

Ecophysiology of Australian Arid-Zone Reptiles

  • S. Don Bradshaw
Chapter

Abstract

Australia’s reptilian fauna is much richer in number of species than that of other desert regions of the world but their ecophysiology has been little studied, and we only have speculations and hypotheses to account for their abundance and diversity. There appears to be no study to date of temperature regulation or osmoregulation of a desert snake, and only a single one of an arid-zone gecko, and most published work has focused on agamid and varanid lizards. A number of agamids have been found to be semelparous, dying after breeding in spring, and thereby avoiding the need for specific adaptations to survive the long, hot and dry summer period. Such specific adaptations have yet to be identified and the inherently low rates of water turnover and resource utilisation of Australian reptiles, coupled with ectothermy and wide thermal safety zones, appear to be the primary reason for their success in arid environments, although they may face future challenges from global warming.

Notes

Glossary

Ectotherm

An animal that derives its body heat from an external source, such as the sun.

Eccritic or preferred body temperature (PBT)

The mean body temperature maintained behaviourally by a reptile when placed in a thermal gradient.

Mean body temperature (MBT)

The average body temperature of a reptile when active, which may differ from the PBT because of a lack of thermal resources.

Agamid

A lizard belonging to the family Agamidae, also called dragon lizard, e.g. the ornate dragon lizard, Ctenophorus ornatus.

Varanid

A lizard belonging to the family Varanidae, also called monitor lizards, e.g. the perentie, Varanus giganteus.

Index of thermal exploitation (Ex)

A ratio calculated by dividing the time that a lizard spends within its set-point range by the time available for the animal to exploit this temperature range and describes the thermoregulatory characteristics of ectotherms in a heterogeneous thermal environment.

CTMax

The critical thermal maximum, or highest body temperature, above which the animal is unable to recover.

FMR

Field metabolic rate. The rate of metabolism of a free-ranging animal in its natural habitat measured as either the rate of oxygen consumption or carbon dioxide production, usually with the doubly-labelled water method.

Scincid

A lizard belonging to the family Scincidae, also called skinks, e.g., the bobtail goanna, Tiliqua rugosa.

Vasotocin (AVT, arginine vasotocin)

A peptide hormone released from the posterior lobe of the pituitary gland of reptiles that enhances water reabsorption from the kidney and also lowers the PBT.

Hypernatraemia

An increase in the concentration of sodium ions in the blood above normal hydrated levels.

PT (panting threshold)

The body temperature at which some lizards open their mouth (gape) and increase their respiratory rate (panting).

Metanephric kidney

The structurally more complex kidney of higher vertebrates, which in the case of birds and mammals, is capable of producing an hyperosmotic urine (i.e. one with an osmotic pressure greater than the plasma).

Cephalic salt glands

Specialised glands found in many reptiles that assist in osmoregulation by secreting a concentrated salt solution rich in either sodium or potassium. All are located in the head (nose, eye or tongue) and hence called ‘cephalic’.

Anuric

Ceasing to produce urine; seen in many lizards when feeding on diets rich in salt.

Semelparous

Animals, such as salmon, that die after breeding only once. Named after the unfortunate Semelae, mother of Bacchus, who succumbed after a night of passion with the Greek God Zeus.

References

  1. Ast JC (2001) Mitochondrial DNA evidence and evolution in Varanoidae (Squamata). Cladistics 17:211CrossRefGoogle Scholar
  2. Avery RA (1982) Field studies of body temperature temperatures and thermoregulation. In: Gans C, Pough FH (eds) Biology of the Reptilia. Academic Press, New York, pp 211–226Google Scholar
  3. Bradley AJ (2003) Stress, hormones and mortality in small carnivorous marsupials. In: Jones ME, Dickman CR, Archer M (eds) Predators with pouches: the biology of carnivorous marsupials. CSIRO, CollingwoodGoogle Scholar
  4. Bradshaw SD (1981) Ecophysiology of Australian desert lizards: studies on the genus Amphibolurus. In: Keast A (ed) Biogeography and ecology in Australia. Junk, Den HaagGoogle Scholar
  5. Bradshaw SD (1986) Ecophysiology of desert reptiles. Academic Press, SydneyGoogle Scholar
  6. Bradshaw SD (1988) Desert reptiles: a case of adaptation or pre-adaptation? J Arid Environ 14:155–174Google Scholar
  7. Bradshaw SD (1997) Homeostasis in desert reptiles. Springer, Berlin/HeidelbergCrossRefGoogle Scholar
  8. Bradshaw SD (2017) A state of non-specific tension in living matter? Stress in Australian animals. Gen Comp Endocrinol 244:118–129CrossRefPubMedGoogle Scholar
  9. Bradshaw SD, De’ath G (1991) Variation in condition indices due to climatic and seasonal factors in an Australian desert lizard, Amphibolurus nuchalis. Aust J Zool 39:373–385CrossRefGoogle Scholar
  10. Bradshaw SD, Main AR (1968) Behavioural attitudes and regulation of temperature in Amphibolurus lizards. J Zool (Lond) 154:193–221CrossRefGoogle Scholar
  11. Bradshaw SD, Saint Girons H, Bradshaw FJ (1991) Patterns of breeding in two species of agamid lizards in the arid sub-tropical Pilbara region of Western Australia. Gen Comp Endocrinol 82:407–424CrossRefPubMedGoogle Scholar
  12. Bradshaw SD, Ladyman M, Stewart T (2007) Effect of hypernatraemia and the neurohypophysial peptide, arginine vasotocin (AVT), on behavioural thermoregulation in the agamid lizard, Ctenophorus ornatus. Gen Comp Endocrinol 150:34–40CrossRefPubMedGoogle Scholar
  13. Byrne M, Yeates DK, Joseph L, Kearney M, Bowler J, Williams AJ, Cooper S, Donnellan SC, Keogh S, Leys R, Melville J, Murphy DJ, Porch N, Wyrwoll KH (2008) Birth of a biome: insights into the assembly and maintenance of the Australian arid zone biota. Mol Ecol 17:4398–4417CrossRefGoogle Scholar
  14. Christian KC, Green B (1994) Seasonal energetics and water turnover of the Frillneck Lizard, Chlamydosaurus kingii, in the wet-dry tropics of Australia. Herpetologica 50(3):274–281Google Scholar
  15. Christian KA, Weavers BW (1996) Thermoregulation of monitor lizards in Australia: an evaluation of methods in thermal biology. Ecol Monogr 66(2):139–157CrossRefGoogle Scholar
  16. Christian CS, Corbett LK, Green B (1995) Seasonal activity and energetics of two species of varanid lizards in tropical Australia. Oecologia 103:349–357CrossRefPubMedGoogle Scholar
  17. Christian K, Bedford GS, Green B, Schultz T, Newgrain K (1998) Energetics and water flux of the marbled velvet gecko (Oedura marmorata) in tropical and temperate habitats. Oecologia 116:336–342CrossRefPubMedGoogle Scholar
  18. Christian K, Webb JK, Schultz T, Green B (2007) Effects of seasonal variation in prey abundance on field metabolism, water flux, and activity of a tropical ambush foraging snake. Physiol Biochem Zool 80:522–533CrossRefPubMedGoogle Scholar
  19. Cogger HG (1974) Thermal relations of the mallee dragon, Amphibolurus fordii (Lacertilia: Agamidae). Aust J Zool 22:319–339CrossRefGoogle Scholar
  20. Cogger HG (1978) Reproductive cycles, fat body cycles, and sociosexual behaviour in the Mallee dragon, Amphibolurus fordi (Lacertilia: Agamidae). Aust J Zool 26:653–672CrossRefGoogle Scholar
  21. Cooper CE (2017) Endocrinology of osmoregulation and thermoregulation of Australian desert tetrapods: a historical perspective. Gen Comp Endocrinol 244:186–200CrossRefPubMedGoogle Scholar
  22. Cowles RB, Bogert CM (1944) A preliminary study of the thermal requirements of desert reptiles. Bull Am Mus Nat Hist 83:265–296Google Scholar
  23. Dantzler WH, Bradshaw SD (2009) Reptiles. In: Evans D (ed) Osmotic and ionic regulation: cells and animals. CRC Press (Taylor & Francis Group), New YorkGoogle Scholar
  24. Dickman CR, Letnic M, Mahon PS (1999) Population dynamics of two species of dragon lizards in arid Australia: the effect of rainfall. Oecologia 119:357–366CrossRefPubMedGoogle Scholar
  25. Dupré KR, Crawford EC (1985a) Control of panting in the desert iguana: roles for peripheral temperatures and the effect of dehydration. J Exp Zool 235:341–347CrossRefPubMedGoogle Scholar
  26. Dupré RK, Crawford EC (1985b) Behavioral thermoregulation during dehydration and osmotic loading of the desert iguana. Physiol Zool 58:357–363CrossRefGoogle Scholar
  27. Ford SS, Bradshaw SD (2006) Kidney function and the rôle of arginine vasotocin (AVT) in three agamid lizards from differing habitats in Western Australia. Gen Comp Endocrinol 147:62–69CrossRefPubMedGoogle Scholar
  28. Fuller S, Baverstock PR, King D (1998) Biogeographic origins of goannas (Varanidae): a molecular perspective. Mol Phylogenet Evol 9:294–307CrossRefPubMedGoogle Scholar
  29. Gould SJ, Lewontin RC (1979) The spandrels of San Marco and the Panglossian paradigm: a critique of the adaptationist programme. Proc R Soc Lond B 205:581–598CrossRefPubMedGoogle Scholar
  30. Gould SJ, Vrba ES (1982) Exaptation – a missing term in the science of form. Paleobiology 8:4–15CrossRefGoogle Scholar
  31. Green B, King D, Butler WH (1986) Water, sodium and energy turnover in free-living Perenties, Varanus giganteus. Aust Wildl Res 13:589–595CrossRefGoogle Scholar
  32. Greer AE (1980) Critical thermal maximum temperatures in Australian scincid lizards: their ecological and evolutionary significance. Aust J Zool 28:98–102CrossRefGoogle Scholar
  33. Greer AE (1990) The biology and evolution of Australian lizards. Surrey Beatty & Sons, SydneyGoogle Scholar
  34. Greer AE (2000) The biology and evolution of Australian snakes. Q Rev Biol 75:67–68CrossRefGoogle Scholar
  35. Heatwole H (1970) Thermal ecology of the desert dragon, Amphibolurus inermis. Ecol Monogr 40:425–457CrossRefGoogle Scholar
  36. Heatwole H (1976) Reptile ecology. University of Queensland Press, QueenslandGoogle Scholar
  37. Henle K (1991) Life history patterns in lizards of the arid and semiarid zone of Australia. Oecologia 88:347–358CrossRefPubMedGoogle Scholar
  38. Hertz PE, Huey RB, Stevenson RD (1993) Evaluating temperature regulation by field-active ectotherms: the fallacy of the inappropriate question. Am Nat 142:796–818CrossRefPubMedGoogle Scholar
  39. Hoppeler H (2015) Epigenetics in comparative physiology. J Exp Biol 218:6CrossRefPubMedGoogle Scholar
  40. Huey RB (1982) Temperature, physiology, and the ecology of reptiles. In: Gans C, Pough FH (eds) Biology of the Reptilia. Academic Press, New YorkGoogle Scholar
  41. Hugall AF, Lee SY (2004) Molecular claims of Gondwanan age for Australian agamid lizards are untenable. Mol Biol Evol 21:2102–2110CrossRefPubMedGoogle Scholar
  42. Hugall AF, Foster R, Hutchinson M, Lee SY (2008) Phylogeny of Australasian agamid lizards based on nuclear and mitochondrial genes: implications for morphological evolution and biogeography. Biol J Linn Soc 93:343–358CrossRefGoogle Scholar
  43. Jennings DH, Moore MC, Knapp R, Matthews L, Orchinick M (2000) Plasma steroid-binding globulin mediation of differences in stress reactivity in alternate male phenotypes in tree lizards, Urosaurus ornatus. Gen Comp Endocrinol 120:289–299CrossRefPubMedGoogle Scholar
  44. King D, Green B (1999) Goannas. UNSW Press, SudneyGoogle Scholar
  45. King D, Green B, Butler H (1989) The activity pattern, temperature regulation and diet of Varanus giganteus on Barrow Island, Western Australia. Wildl Res 16:41–47CrossRefGoogle Scholar
  46. Kuchling G (1999) The reproductive biology of the Chelonia. Springer, HeidelbergCrossRefGoogle Scholar
  47. Ladyman M, Bradshaw SD (2003) The influence of dehydration on the thermal preferences of the Western Tiger snake, Notechis scutatus. J Comp Physiol B 173:239–246PubMedGoogle Scholar
  48. Ladyman M, Bradshaw SD, Bradshaw FJ (2003) Hypernatraemia and its effect on temperature regulation and levels of the hormone aginine vasotocin in the Western Tiger snake, Notechis scutatus. J Comp Physiol BGoogle Scholar
  49. Ladyman MT, Bradshaw SD, Bradshaw FJ (2006) Physiological and hormonal control of thermal depression in the Tiger snake, Notechis scutatus. J Comp Physiol B 176:547–557Google Scholar
  50. Licht P, Dawson WR, Shoemaker VH, Main AR (1966) Observations on the thermal relations of Western Australian lizards. Copeia 1966:97–110CrossRefGoogle Scholar
  51. Lillywhite HB (1980) Behavioural thermoregulation in Australian elapid snakes. Copeia 1980:452–458CrossRefGoogle Scholar
  52. Lillywhite H (2006) Water relations of tetrapod integument. J Exp Biol 209:200–226CrossRefGoogle Scholar
  53. Martin HA (2006) Cenozoic climatic change and the development of the arid vegetation in Australia. J Arid Environ 66:533–563CrossRefGoogle Scholar
  54. Melville J, Schulte Ii JA (2001) Correlates of active body temperatures and microhabitat occupation in nine species of central Australian agamid lizards. Austral Ecol 26:660–669CrossRefGoogle Scholar
  55. Morton SR, James CD (1988) The diversity and abundance of lizards in arid Australia: a new hypothesis. Am Nat 132:237–256CrossRefGoogle Scholar
  56. Nagy KA (1982) Field studies of water relations. In: Gans C, Pough H (eds) Biology of the Reptilia. Academic Press, New YorkGoogle Scholar
  57. Nagy KA, Bradshaw SD (1995) Energetics, osmoregulation and food consumption by free-living desert lizards, Ctenophorus (=Amphibolurus) nuchalis. Amphibia-Reptilia 16:25–35.Google Scholar
  58. Nagy KA, Peterson CC (1988) Scaling of water flux rate in animals. Univ Calif Publ Zool 120:1–172Google Scholar
  59. Oliver PM, Bauer AM (2011) Systematics and evolution of the Australian knobtail geckos (Nephrurus, Carphodactylidae, Gekkota): pleisomorphic grades and progressive biome shifts through the Miocene. Mol Phylogenet Evol 59:664–674CrossRefPubMedGoogle Scholar
  60. Oliver PM, Sanders KL (2009) Molecular evidence for Gondwanan origins of multiple lineages within a diverse gecko radiation. J Biogeogr 36:2044–2055CrossRefGoogle Scholar
  61. O’shea JE, Bradshaw SD, Stewart T (1993) The renal vasculature and excretory system of the agamid lizard Ctenophorus ornatus. J Morphol 217:287–299CrossRefPubMedGoogle Scholar
  62. Pianka ER (1986) Ecology and natural history of desert lizards. Princeton University Press, PrincetonCrossRefGoogle Scholar
  63. Pianka E (1989) Desert lizard diversity: additional comments and some data. Am Nat 134:344–364CrossRefGoogle Scholar
  64. Pianka E (2014) Rarity in Australian desert lizards. Austral Ecol 13:214–224CrossRefGoogle Scholar
  65. Powney GD, Grenyer, Orme CDL, Owens IPF, Meiri S (2010) Hot, dry and different: Australian lizard richness is unlike that of mammals, amphibians and birds. Glob Ecol Biogeogr 19:386–396CrossRefGoogle Scholar
  66. Rosen PC (1990) Comparative field study thermal preferenda in garter snakes (Thamnophis). J Herpetol 25:301–312CrossRefGoogle Scholar
  67. Saint Girons H, Bradshaw SD (1987) Aspects of variation in histology and cytology of the external nasal glands of Australian lizards. J R Soc West Aust 69:117–121Google Scholar
  68. Saint Girons H, Rice GE, Bradshaw SD (1981). Histologie comparée et ultrastructure de la glande nasale externe de quelques Varanidae (Reptilia, Lacertilia). Annales Scientifiques et Naturelles en Zoologie de Paris, 3, 13ème Ser.:15–21Google Scholar
  69. Scanlon JD, Lee MSY (2004) Phylogeny of Australasian venomous sea snakes (Colubridae, Elapidae, Hydrophiinae) based on phenotypic and molecular evidence. Zool Scr 33:335–366CrossRefGoogle Scholar
  70. Schulte J, Melville J, Larson A (2003) Molecular phylogenetic evidence for ancient divergence of lizard taxa on either side of Wallace’s line. Proc R Soc Lond B 270:597–603CrossRefGoogle Scholar
  71. Shine R (1987) Intraspecific variation thermoregulation, movements and habitat use by Australian blacksnakes, Pseudechis porophyriacus (Elapidae). J Herpetol 21:165–177CrossRefGoogle Scholar
  72. Stebbins RC, Barwick RE (1968) Radiotelemetric study of thermoreulation in a lace monitor. Copeia 1968:541–547CrossRefGoogle Scholar
  73. Thompson GG, Bradshaw SD, Withers PC (1997) Energy and water turnover rates of a free-living and captive goanna, Varanus caudolineatus (Lacertilia: Varanidae). Comp Biochem Physiol 116A:105–111CrossRefGoogle Scholar
  74. Underwood G (1957) On lizards of the family Pygopodidae: a contribution to the morphology and phylogeny of the Squamata. J Morphol 100:207–268CrossRefGoogle Scholar
  75. Whitfield CL, Livezey RL (1973) Thermoregulatory patterns in lizards. Physiol Zool 46:285–296CrossRefGoogle Scholar
  76. Withers PC, Bradshaw SD (1995) Water and energy balance of the mountain devil Moloch horridus: is the devil a sloth? Amphibia-Reptilia 16:47–54CrossRefGoogle Scholar
  77. Zucher A (1980) Procedural and anatomical considerations of the determination of cutaneous water loss in reptiles. Copeia 1980:425–439CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Biological SciencesThe University of Western AustraliaCrawley (Perth)Australia

Personalised recommendations