With the common name “shark” we can describe more than 400 different species of fishes belonging to the class “Chondrichthyes”, characterized by having a cartilaginous skeleton . Thanks to the innumerable adaptations that can be found in this group of predators, they managed to conquer almost every ecological niche possible in the marine environment, playing a key role in controlling the balance of the whole ecosystem. Their biological and physiological adaptations have been tailored by evolution in order to cope with different challenges of living in the ocean; here are SOME of the incredible characteristics of sharks:
If we explored all the different biological adaptations of shark species, this article would never finish. Think about the recent discovery of the remarkable longevity of Greenland shark (Somniosus microcephalus), estimated to be 392 ± 120 years , or the ability of female zebra shark (Stegostoma fasciatum) to “switch” to asexual reproduction: although she hadn’t been in contact with any male in three years, the shark gave birth to 3 pups .
Sharks are incredible creatures, characterized by incredible adaptations that allowed them to conquer innumerable ecological niches but unfortunately their numbers are in decline . It has been proven that a exploited elasmobranch communities in coastal, demersal, and pelagic habitats could have dramatic consequences on the balance of the whole ecosystem . It is fundamental that we continue to increase the awareness of shark roles and importance in the ecosystem; we need to try our best to protect these remarkable animals by supporting conservation projects in any mean.
Cover Photo: BRIAN J. SKERRY, NATIONAL GEOGRAPHIC CREATIVE
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