Biologic evolution

The motor that makes the water current in the water tank of seawater
has not worked.
Though it was thought that it had broken
When the manual of the motor is read, it seems to have regularly to
clean it.
The propeller in the motor is cleaned.
Sand was considerably attached.
After sand is taken, it is and completes washing in clear water.
It was good because it had come to move.

The water current comes not to move.
Shellfishes in the water tank had movement.
A small ark shell went out and began to breathe by opening the shell and
closing from among sand.
There is no what seen because small red is a state in the state of diving
in sand usually.
Small red has dived in sand when the motor begins to work.

Apparently, there seems to be a water current in sand though it was thought that
only the surface of sand was influenced by the water current.
Shellfishes who exist in sand seem to have neither going out on sand all the way by
it nor breathing in oxygen.
The shellfish hides oneself in sand in the current water current type though the
shellfish occasionally saw the appearance in which the water pipe is extended to
the surface of sand and oxygen is taken when it is a type to which oxygen is sent
by the air stone with the air pump that had been used before, and there is not
seeing the water pipe.