Older than expected: Teeth reveal the origin of the tiger shark

Modern Tiger shark (© Michael Vogelsang / www.seapicture.de) - With a total length of up to 5.5m, the tiger shark is one of the largest predatory sharks known today. This shark is a cosmopolitan species occurring in all oceans worldwide. It is characterized by a striped pattern on its back, which is well marked in juveniles but usually fades in adults. An international team of researchers led by Julia Türtscher from the University of Vienna examined the fossil record of these apex predators and found out that modern tiger sharks are older than previously thought and that several tiger shark species existed in past compared to the single species living today. The results of this study are published in the journal "Paleobiology". The fossil history of modern sharks reaches back to the Permian, about 295 million years ago. Complete fossil shark skeletons are very rare - the skeleton, which consists almost entirely of cartilage, is only preserved under very special circumstances during the fossilization processes.