Im 1997, a team of researchers at Zurich UniverS1ty
Im Switzerland first witnessed dolphins using tool8 1
This is probabIy the
Shark Bay、Western Australia.
als.
m
only known case of tool use by marine mnarn1
her
Dolphins are thought to be clever animals becau8@ 【
1
brain-to-body-mass ratio is greater than that Oo
other animals except humans. But previously they had
not been considered to be tool-users.
When the researchers were observing the dolphins
im Shark Bay, they saw something strange over their 」
beaks. It looked 8s、 they had massive tumors. The
objects turned out to be marine sponges broken off from
the seabed. The dolphins were holding sponges over
ther beaks and appeared to be usmg them as a fishing
tool while they were searching the sea foor. It jisi
believed that these sponges help protect the dolphins*
beaks from debris. Without Sponges, the dolphins might
hurt their beaks.
