at around four to five years of age and proposed a possible revision to the measurements of the growth rings in FHSM VP-2187. The lifespan of FHSM VP-2187 and maximum lifespan of C. mantelli was also proposed to be revised to 18 and 21 years respectively using the new measurements. A 2019 study led by Italian scientist Jacopo Amalfitano briefly measured the vertebrae from two C. mantelli fossils and found that the older individual died at around 26 years of age. Measurements were also conducted on other C. mantelli skeletons and a vertebra of C. agassizensis, yielding results of similar rates of rapid growth in early stages of life. Such rapid growth within mere years could have helped Cretoxyrhina better survive by quickly phasing out of infancy and its vulnerabilities, as a fully grown adult would have few natural predators. The 2013 study also identified a syntype tooth of C. mantelli from England and calculated the individual's maximum length of , making the tooth the largest known specimen yet. When applying the allometric scaling used in Shimada (2008), a C. mantelli of such length would yield an estimated body mass of around . The graph below represents the length growth per year of FHSM VP-2187 according to Shimada (2008): Other species were estimated to have been significantly smaller. C. denticulata and C. vraconensis reached a total body length of up to as an adult. Based on allometric scaling, individuals of such length would have weighed about . C. agassizensis was even smaller, with an estimated total body length of up to based on a tooth specimen (P2989.152) measuring tall. Paleobiology Prey relationships The powerful kinetic jaws, high-speed capabilities, and large size of Cretoxyrhina suggest a very aggressive predator. Cretoxyrhinas association with a diverse number of fossils showing signs of devourment confirms that it was an active apex predator that fed on much of the variety of marine megafauna in the Late Cretaceous. The highest trophic level it occupied was a position shared only with large mosasaurs such as Tylosaurus during the latter stages of the Late Cretaceous. It played a critical role in many marine ecosystems.Cretoxyrhina mainly preyed on other active predators including ichthyodectids (a type of large fish that includes Xiphactinus), plesiosaurs, turtles, mosasaurs, and other sharks. Most fossils of Cretoxyrhina feeding upon other animals consist of large and deep bite marks and punctures on bones, occasionally with teeth