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Evolution

Warm-hearted crocs

Nature volume 434, pages 833–834 (2005)Cite this article

Our ideas about how crocodiles evolved have just taken a battering. It seems that these cold-blooded creatures, with their limited capacity for prolonged activity, might have had active, warm-blooded ancestors.

A crocodile, quietly submerged, waiting to ambush its next meal, is a testament to the benefits of allowing the environment to determine body temperature. Cool water keeps the metabolic rate low, allowing astonishing periods between breaths that can range into hours. Writing in Physiological and Biochemical Zoology, Seymour and colleagues1 propose that inside these armoured predators beats a heart that harks back to ancestors that were terrestrial, active and — most surprisingly — ‘warm-blooded’.

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Figure 1: Pump rooms.

References

  1. Seymour, R. S., Bennett-Stamper, C. L., Johnston, S. D., Carrier, D. R. & Grigg, G. C. Physiol. Biochem. Zool. 77, 1051–1067 (2004).

    Article  Google Scholar 

  2. Bennett, A. F. J. Exp. Biol. 160, 1–23 (1991).

    CAS  PubMed  Google Scholar 

  3. Platzack, B. & Hicks, J. W. Am. J. Physiol. 281, R1295–R1301 (2001).

    CAS  Google Scholar 

  4. Wang, T., Altimiras, J. & Axelsoson, M. J. Exp. Biol. 205, 2717–2723 (2003).

    Google Scholar 

  5. Carrier, D. R. & Farmer, C. G. Am. Zool. 40, 87–100 (2000).

    Google Scholar 

  6. Janke, A. & Arnason, U. Mol. Biol. Evol. 14, 1266–1272 (1997).

    Article  CAS  Google Scholar 

  7. Bennett, A. F. & Ruben, J. A. in The Ecology and Biology of Mammal-like Reptiles (eds Hotton, N., MacLean, P. D., Roth, J. J. & Roth, E. C.) (Smithsonian Institution, Washington DC, 1986).

    Google Scholar 

  8. Hillenius, W. J. & Ruben, J. A. Physiol. Biochem. Zool. 77, 1068–1072 (2004).

    Article  Google Scholar 

Download references

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  1. the Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, 92697-2525, California, USA

    Adam P. Summers

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  1. Adam P. Summers
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Summers, A. Warm-hearted crocs. Nature 434, 833–834 (2005). https://doi.org/10.1038/434833a

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