title: An exceptionally preserved Eocene shark and the rise of modern predator-prey interactions in the coral reef food web.
abstract: BACKGROUND
  Following extreme climatic warming events, Eocene Lagerstätten document aquatic and terrestrial vertebrate faunas surprisingly similar to modern counterparts. This transition in marine systems is best documented in the earliest teleost-dominated coral reef assemblage of Pesciara di Bolca, northern Italy, from near the end of the Eocene Climatic Optimum. Its rich fauna shows similarities with that of the modern Great Barrier Reef in niche exploitation by and morphological disparity among teleost primary consumers. However, such paleoecological understanding has not transcended trophic levels above primary consumers, particularly in carcharhiniform sharks.
  
  
  RESULTS
  We report an exceptionally preserved fossil school shark (Galeorhinus cuvieri) from Pesciara di Bolca. In addition to the spectacular preservation of soft tissues, including brain, muscles, and claspers, this male juvenile shark has stomach contents clearly identifiable as a sphyraenid acanthomorph (barracuda). This association provides evidence that a predator-prey relationship between Galeorhinus and Sphyraena in the modern coral reefs has roots in the Eocene. A growth curve of the living species of Galeorhinus fitted to G. cuvieri suggests that all specimens of G. cuvieri from the lagoonal deposits of Bolca represent sexually and somatically immature juveniles.
  
  
  CONCLUSIONS
  The modern trophic association between higher-degree consumers (Galeorhinus and Sphyraena) has a counterpart in the Eocene Bolca, just as Bolca and the Great Barrier Reef show parallels among teleost primary consumers. Given the age of Bolca, trophic networks among consumers observed in modern coral reefs arose by the exit from the Climatic Optimum. The biased representation of juveniles suggests that the Bolca Lagerstätte served as a nursery habitat for G. cuvieri. Ultraviolet photography may be useful in probing for exceptional soft tissue preservation before common acid preparation methods.
authors.affiliation: Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Alma Mater Studiorum, Università di Bologna, Via Zamboni 67, Bologna, 40126 Italy.|Museo Geologico Giovanni Capellini, Alma Mater Studiorum, Università di Bologna, Via Zamboni 63, Bologna, 40126 Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Fanti
authors.affiliation: Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Alma Mater Studiorum, Università di Bologna, Via Zamboni 67, Bologna, 40126 Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Minelli
authors.affiliation: Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Alma Mater Studiorum, Università di Bologna, Via Zamboni 67, Bologna, 40126 Italy.
authors.forename: Gabriele Larocca
authors.initials: GL
authors.lastname: Conte
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9 Canada.
authors.forename: Tetsuto
authors.initials: T
authors.lastname: Miyashita
keywords: Bolca; Carcharhinuformes; Early eocene climatic optimum; Galeorhinus; Nursery habitat; Soft tissue; Sphyraena; Stomach content; Triakidae; von Bertalanffy