Dolphins do have organs with which they pick up things like rocks or shells and they are able to give them to each other.
They use their sexual organs as "hands"! Both males and females.
In the tree of life brains are correlated much more strongly with locomotion than with hands. The moment you need to do (inverse) kinematics to plan an immediate action, and to plan sequences of motions, and to plan a hunting or fleeing strategy, is what put pressure to evolve brains, static lifeforms can be very complex and have complicated genomes, but brains you wont find in them...
Dolphins do have organs with which they pick up things like rocks or shells and they are able to give them to each other.
They use their sexual organs as "hands"! Both males and females.
In the tree of life brains are correlated much more strongly with locomotion than with hands. The moment you need to do (inverse) kinematics to plan an immediate action, and to plan sequences of motions, and to plan a hunting or fleeing strategy, is what put pressure to evolve brains, static lifeforms can be very complex and have complicated genomes, but brains you wont find in them...