On her deep-sea dives, wildlife biologist Angela Ziltener of the College of Zurich usually observed Indo-Pacific bottlenosed dolphins doing one thing intriguing. The dolphins (Tursiops aduncus) would line as much as take turns brushing their our bodies in opposition to corals or sea sponges lining the seafloor. After greater than a decade as an “adopted” member of the pod — a standing that allow Ziltener rise up shut with out disturbing the animals — she and her crew might have found out why the animals behave this manner: The dolphins might use corals and sea sponges as their very own non-public pharmacies.
The invertebrates make antibacterial compounds — in addition to others with antioxidant or hormonal properties — which are in all probability launched into the waters of the Northern Purple Sea when dolphins make contact, Ziltener and colleagues report Could 19 in iScience. So the rubbing may assist dolphins keep wholesome pores and skin.
Ziltener captured video displaying members of the pod utilizing corals as in the event that they had been a shower brush, swimming via to rub numerous elements of their our bodies. Oftentimes it’s a peaceable social gathering. “It’s not like they’re preventing one another for the flip,” Ziltener says. “No, they wait after which they undergo.” Different occasions, a person dolphin will arrive at a patch of coral by itself.
However the dolphins gained’t buff their our bodies in opposition to simply any corals, Ziltener says. They’re choosy, primarily rubbing up in opposition to gorgonian corals (Rumphella aggregata) and leather-based corals (Sarcophyton sp.), in addition to a form of sea sponge (Ircinia sp.).
Ziltener and colleagues analyzed one-centimeter slices taken from wild corals and sponges. The crew recognized 17 compounds general, together with 10 with antibacterial or antimicrobial exercise. It’s doable that because the dolphins swim via the corals, the compounds assist shield the animals from pores and skin irritations or infections, says coauthor Gertrud Morlock, an analytical chemist at Justus Liebig College Giessen in Germany.
Different animals, together with chimpanzees, can self-medicate (SN: 11/3/90). Marine biologist Jeremy Kiszka of Florida Worldwide College in Miami says the brand new research convinces him that the dolphins are utilizing corals and sea sponges for that function. However, he says, further experiments are essential to show the hyperlink. Lab assessments, for example, may assist establish the forms of micro organism that the compounds may work in opposition to.
Ziltener agrees there’s extra to be executed. As an illustration, it’s additionally doable that along with prevention, dolphins use corals and sea sponges to deal with energetic pores and skin infections, she says, however the crew has but to see proof of a coral treatment. Subsequent up although, Ziltener says, is determining whether or not dolphins desire to rub particular physique elements on particular corals in such an “underwater spa.”