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Histological, chemical, and morphological reexamination of the “heart” of a small Late Cretaceous Thescelosaurus

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Abstract

A three-dimensional, iron-cemented structure found in the anterior thoracic cavity of articulated Thescelosaurus skeletal remains was hypothesized to be the fossilized remains of the animal’s four-chambered heart. This was important because the finding could be interpreted to support a hypothesis that non-avian dinosaurs were endothermic. Mammals and birds, the only extant organisms with four-chambered hearts and single aortae, are endotherms. The hypothesis that this Thescelosaurus has a preserved heart was controversial, and therefore, we reexamined it using higher-resolution computed tomography, paleohistological examination, X-ray diffraction analysis, X-ray photoelectron spectroscopy, and scanning electron microscopy. This suite of analyses allows for detailed morphological and chemical examination beyond what was provided in the original work. Neither the more detailed examination of the gross morphology and orientation of the thoracic “heart” nor the microstructural studies supported the hypothesis that the structure was a heart. The more advanced computed tomography showed the same three areas of low density as the earlier studies with no evidence of additional low-density areas as might be expected from examinations of an ex situ ostrich heart. Microstructural examination of a fragment taken from the “heart” was consistent with cemented sand grains, and no chemical signal consistent with a biological origin was detected. However, small patches of cell-like microstructures were preserved in the sandstone matrix of the thoracic structure. A possible biological origin for these microstructures is the focus of ongoing investigation.

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References

  • Allison PA (1988) Konservat-Lagerstatten: cause and classification. Paleobiology 14(4):331–344

    Google Scholar 

  • Anbar AD (2004) Iron stable isotopes: beyond biosignatures. Earth Planet Sci Lett 217(3–4):223–236. doi:10.1016/S0012-821x(03)00572-7

    Article  CAS  Google Scholar 

  • Boyd CA, Brown CM, Scheetz RD, Clarke JA (2009) Taxonomic revision of the basal neornithischian taxa Thescelosaurus and Bugenasaura. J Vertebr Paleontol 29:758–770

    Article  Google Scholar 

  • Briggs DEG (2003) The role of decay and mineralization in the preservation of soft-bodied fossils. Annu Rev Earth Planet Sci 31:275–301. doi:10.1146/Annurev.Earth.31.100901.144746

    Article  CAS  Google Scholar 

  • Brochu CA (2001) Progress and future directions in archosaur phylogenetics. J Paleontol 75:1185–1201

    Article  Google Scholar 

  • Busigny V, Dauphas N (2007) Tracing paleofluid circulations using iron isotopes: a study of hematite and goethite concretions from the Navajo Sandstone (Utah, USA). Earth Planet Sci Lett 254:272–287

    Article  CAS  Google Scholar 

  • Butler RJ, Galton PM (2008) The ‘dermal armour’ of the ornithopod dinosaur Hypsilophodon from the Wealden (Early Cretaceous: Barremian) of the Isle of Wight: a reappraisal. Cretaceous Res 29(4):636–642

    Article  Google Scholar 

  • Butler RJ, Upchurch P, Norman DB (2008) The phylogeny of the ornithischian dinosaurs. J Syst Paleontol 6(01):1–40

    Google Scholar 

  • Chan MA, Ormö J, Park AJ, Stich M, Souza-Egipsy V, Komatzu G (2007) Models of iron oxide concretion formation: field, numerical, and laboratory comparisons. Geofluids 7(3):356–368

    Article  CAS  Google Scholar 

  • Cheng C-H, Lehmann J, Thies JE, Burton SD, Engelhard MH (2006) Oxidation of black carbon by biotic and abiotic processes. Org Geochem 37:1477–1488

    Article  CAS  Google Scholar 

  • Chiappe LM, Coria RA, Dingus L, Jackson F, Chinsamy A, Fox M (1998) Sauropod dinosaur embryos from the Late Cretaceous of Patagonia. Nature 396:258–261

    Article  CAS  Google Scholar 

  • Chin K, Eberth DA, Schweitzer MH, Rando TA, Sloboda WJ, Horner JR (2003) Remarkable preservation of undigested muscle-tissue within a Late Cretaceous tyrannosaurid coprolite from Alberta, Canada. Palaios 18(3):286–294

    Article  PubMed  Google Scholar 

  • Coria RA, Chiappe LM (2007) Embryonic skin from Late Cretaceous sauropods (Dinosauria) of Auca Mahuevo, Patagonia, Argentina. J Paleontol 81:1528–1532

    Article  Google Scholar 

  • Cornell RM, Schneider W (1989) Formation of goethite from ferrihydrite at physiological pH under the influence of cysteine. Polyhedron 8(2):149–155

    Article  CAS  Google Scholar 

  • Cornell RM, Schwertmann U (2003) The iron oxides: structure, properties, reactions, occurrences, and uses. Wiley, Weinheim

    Google Scholar 

  • Dal Sasso C, Signore M (1998) Exceptional soft-tissue preservation in a theropod dinosaur from Italy. Nature 392:383–387

    Article  CAS  Google Scholar 

  • Duliu OG, Tufan MS, Szobotka SA (1997) Computer axial tomography investigation of polymetallic nodules. Mar Geol 138(3–4):303–311

    Article  CAS  Google Scholar 

  • Farrell AP, Gamperl AK, Francis ETB (1998) Comparative aspects of heart morphology. In: Gans C, Gaunt AS (eds) Biology of the Reptilia, volume 19, morphology G, visceral organs. Society for the Study of Amphibians and Reptiles, Ithaca, pp 375–424

    Google Scholar 

  • Fisher PE, Russell DA, Stoskopf MK, Barrick RE, Hammer M, Kuzmitz AA (2000) Cardiovascular evidence for an intermediate or higher metabolic rate in an ornithischian dinosaur. Science 288(5465):503–505

    Article  CAS  PubMed  Google Scholar 

  • Gauthier J (1986) Saurischian monophyly and the origin of birds. Mem California Acad Sci 8:1–55

    Google Scholar 

  • Goldstein J, Newbury DE, Joy DC, Echlin P, Lyman CE, Lifshin E (2003) Scanning electron microscopy and X-ray microanalysis, volume 1, 3rd edn. Springer, New York

    Google Scholar 

  • Hodges RD (1974) Histology of the fowl. Academic, London

    Google Scholar 

  • Julian RJ (1996) Cardiovascular system. In: Riddell C (ed) Avian histopathology, 2nd edn. American Association of Avian Pathologists, New Bolton Center, Kennett Square, pp 70–88

    Google Scholar 

  • Katz AM (2006) Physiology of the heart, 4th edn. Lippincott Williams and Wilkins, Philadelphia

    Google Scholar 

  • Kellner AWA (1996a) Reinterpretation of a remarkably well preserved pterosaur soft tissue from the Early Cretaceous of Brazil. J Vertebr Paleontol 16(4):718–722

    Article  Google Scholar 

  • Kellner AWA (1996b) Fossilized theropod soft tissue. Nature 379(6560):32

    Article  CAS  Google Scholar 

  • Krautwald-Junghanns ME, Schulz M, Hagner D, Failing K, Redman T (1995) Transcoelomic two-dimensional echocardiography in the avian patient. J Avian Med Surg 9(1):19–31

    Google Scholar 

  • Martinez-Lemus LA, Miller MW, Jeffrey JS, Odom TW (1998) Echocardiographic evaluation of cardiac structure and function in broiler and Leghorn chickens. Poult Sci 77(7):1045–1050

    CAS  PubMed  Google Scholar 

  • Mozley PS, Davis JM (2005) Internal structure and mode of growth of elongate calcite concretions: evidence for small-scale, microbially induced, chemical heterogeneity in groundwater. Geol Soc Am Bull 117:1400–1412

    Article  CAS  Google Scholar 

  • Patience RL, Baxby M, Bartle KD, Perry DL, Rees AGW, Rowland SJ (1992) The functionality of organic nitrogen in some recent sediments from the Peru upwelling region. Org Geochem 18:161–169

    Article  CAS  Google Scholar 

  • Rowe T, McBride EF, Sereno PC (2001) Dinosaur with a heart of stone. Science 291:783a

    Article  Google Scholar 

  • Russell DA, Fisher PE, Barrick RE, Stoskopf MK (2001) Response: dinosaur with a heart of stone. Science 291:783a

    Article  Google Scholar 

  • Schweitzer MH (2011) Soft tissue preservation in terrestrial Mesozoic vertebrates. Annu Rev Earth Planet Sci 39. doi:10.1146/annurev-earth-040610-133502

  • Sellés-Martinéz J (1996) Concretion morphology, classification and genesis. Earth Sci Rev 41(3–4):177–210

    Article  Google Scholar 

  • Sereno PC (1997) The origin and evolution of dinosaurs. Annu Rev Earth Planet Sci 25(1):435–489. doi:10.1146/annurev.earth.25.1.435

    Article  CAS  Google Scholar 

  • Seymour RS, Bennett-Stamper CL, Johnston SD, Carrier DR, Grigg GC (2004) Evidence for endothermic ancestors of crocodiles at the stem of archosaur evolution. Physiol Biochem Zool 77(6):1051–1067

    Article  PubMed  Google Scholar 

  • Turner-Walker G (2007) The chemical and microbial degradation of bones and teeth. In: Ron Pinhasi SM (ed) Advances in human palaeopathology. Wiley, Chichester, pp 3–29

    Chapter  Google Scholar 

  • Tyson RV (1995) Sedimentary organic matter: organic facies and palynofacies. Chapman & Hall, New York

    Google Scholar 

  • Vairamurthy A, Wang S (2002) Organic nitrogen in geomacromolecules: insights on speciation and transformation with K-edge XANES spectroscopy. Environ Sci Technol 36:3050–3056

    Article  Google Scholar 

  • Webb GJW (1979) Comparative cardiac anatomy of the Reptilia. 3. Heart of crocodilians and an hypothesis on the completion of the inter-ventricular septum of crocodilians and birds. J Morphol 161(2):221–240

    Article  Google Scholar 

  • West MJ, Langille BL, Jones DR (1981) Cardiovascular system. In: King AS, McLelland J (eds) Form and function in birds, volume 2. Academic, London, pp 235–340

    Google Scholar 

  • Witmer LM (1995) The extant phylogenetic bracket and the importance of reconstructing soft issues in fossils. In: Thomason JJ (ed) Functional morphology in vertebrate paleontology. Cambridge University Press, New York, pp 19–33

    Google Scholar 

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Acknowledgments

We gratefully acknowledge the North Carolina Museum of Natural Sciences and B. Bennett for allowing us to reevaluate this important specimen, to show the public the ever-changing face of science in light of new data. We also gratefully acknowledge D. Russell for his willingness to propose the original hypothesis and his fundamental advances to the field of vertebrate paleontology, and we are honored to work with him. Tony Pease assisted with rendering and early interpretation of CT data; F. Stevie at the Advance Imaging Facility at North Carolina State University assisted with XPS analyses; N. Equall and M. Bergeron at the Imaging and Chemical Analysis Laboratory provided assistance with FESEM imaging and analyses and XRD analyses, respectively. The Geological Society of America provided funding, and L. Johnson, C. Boyd, and E. Schroeter gave invaluable feedback on early versions of this manuscript.

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Correspondence to Timothy P. Cleland.

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Fig. S1

Elemental profiles of isolated regions within the petrographic section of the fragment from NCSM 15728 shown in Fig. 4. a Elemental profile of nuclei-like structures labeled in Fig. 4b showing abundant iron and oxygen. b EDX spectrum for the cytoplasm-like area in Fig. 4b showing iron, sulfur, and oxygen. Sodium is also detected in lower abundance. c EDX spectrum for membrane-like area is in Fig. 4b showing abundant iron and sulfur. Carbon and oxygen are detected in lesser quantities. (DOC 213 kb)

Fig. S2

a X-ray diffraction (XRD) analysis of the embedded block of presumed “heart” material from NCSM 15728 showing broad peaks corresponding to all present minerals. Vertical lines represent the theoretical peak distribution for goethite. b X-ray photoelectron spectroscopy (XPS) analyses for three representative powdered samples of the fragment indicating the presence of iron, oxygen, and silicon. No nitrogen or appreciable carbon is present. (DOC 443 kb)

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Cleland, T.P., Stoskopf, M.K. & Schweitzer, M.H. Histological, chemical, and morphological reexamination of the “heart” of a small Late Cretaceous Thescelosaurus . Naturwissenschaften 98, 203–211 (2011). https://doi.org/10.1007/s00114-010-0760-1

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