000058390 001__ 58390
000058390 005__ 20200221144319.0
000058390 0247_ $$2doi$$a10.1371/journal.pone.0153026
000058390 0248_ $$2sideral$$a97275
000058390 037__ $$aART-2016-97275
000058390 041__ $$aeng
000058390 100__ $$0(orcid)0000-0002-7210-1033$$aMoreno-Azanza, Miguel
000058390 245__ $$aCombined use of electron and light microscopy techniques reveals false secondary shell units in Megaloolithidae eggshells
000058390 260__ $$c2016
000058390 5060_ $$aAccess copy available to the general public$$fUnrestricted
000058390 5203_ $$aAbnormalities in the histo- and ultrastructure of the amniote eggshell are often related to diverse factors, such as ambient stress during egg formation, pathologies altering the physiology of the egg-laying females, or evolutionarily selected modifications of the eggshell structure that vary the physical properties of the egg, for example increasing its strength so as to avoid fracture during incubation. When dealing with fossil materials, all the above hypotheses are plausible, but a detailed taphonomical study has to be performed to rule out the possibility that secondary processes of recrystallization have occurred during fossilization. Traditional analyses, such as optical microscopy inspection and cathodoluminescence, have proven not to be enough to understand the taphonomic story of some egg-shells. Recently, electron backscatter diffraction has been used, in combination with other techniques, to better understand the alteration of fossil eggshells. Here we present a combined study using scanning electron microscopy, optical microscopy, cathodoluminescence and electron backscatter diffraction of eggshell fragments assigned to Megaloolithus cf. siruguei from the Upper Cretaceous outcrops of the Cameros Basin. We focus our study on the presence of secondary shell units that mimic most aspects of the ultrastructure of the eggshell mammillae, but grow far from the inner surface of the eggshell. We call these structures extra-spherulites, describe their crystal structure and demonstrate their secondary origin. Our study has important implications for the interpretation of secondary shell units as biological or pathological structures. Thus, electron backscatter diffraction complements other microscope techniques as a useful tool for understanding taphonomical alterations in fossil eggshells.
000058390 536__ $$9info:eu-repo/grantAgreement/ES/MINECO/CGL2013-46169-C2-1-P$$9info:eu-repo/grantAgreement/ES/MINECO/CGL2014-53548-P
000058390 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000058390 590__ $$a2.806$$b2016
000058390 591__ $$aMULTIDISCIPLINARY SCIENCES$$b15 / 63 = 0.238$$c2016$$dQ1$$eT1
000058390 592__ $$a1.236$$b2016
000058390 593__ $$aAgricultural and Biological Sciences (miscellaneous)$$c2016$$dQ1
000058390 593__ $$aMedicine (miscellaneous)$$c2016$$dQ1
000058390 593__ $$aBiochemistry, Genetics and Molecular Biology (miscellaneous)$$c2016$$dQ1
000058390 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000058390 700__ $$0(orcid)0000-0002-4970-6333$$aBauluz, Blanca$$uUniversidad de Zaragoza
000058390 700__ $$0(orcid)0000-0003-1732-9155$$aCanudo Sanagustín, José Ignacio$$uUniversidad de Zaragoza
000058390 700__ $$0(orcid)0000-0002-8427-6199$$aGasca, José Manuel
000058390 700__ $$aTorcida-Baldor, Fidel
000058390 7102_ $$12000$$2655$$aUniversidad de Zaragoza$$bDpto. Ciencias de la Tierra$$cÁrea Paleontología
000058390 7102_ $$12000$$2120$$aUniversidad de Zaragoza$$bDpto. Ciencias de la Tierra$$cÁrea Cristalografía Mineralog.
000058390 773__ $$g11, 5 (2016), e0153026 [17pp]$$pPLoS One$$tPloS one$$x1932-6203
000058390 8564_ $$s2336766$$uhttps://zaguan.unizar.es/record/58390/files/texto_completo.pdf$$yVersión publicada
000058390 8564_ $$s105304$$uhttps://zaguan.unizar.es/record/58390/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000058390 909CO $$ooai:zaguan.unizar.es:58390$$particulos$$pdriver
000058390 951__ $$a2020-02-21-13:40:38
000058390 980__ $$aARTICLE