**System Information**
Operating system and graphics card NOT Relevant
**Blender Version**
2.76 2015/10/11 06.55 hash 48f7dd6
**Short description of error**
If you separate part of a mesh to make a new object, any f-curves in the orginal object are shared by the newly separated object. These cannot be independently edited. They seem to share a single instance.
**Exact steps for others to reproduce the error**
Start with a mesh (default cube for example)
Animate it.
Edit it, select some part of it and use Separate by selected.
Select the new object
Go to F-curves.
You should see copies of the curves from the orginal object's animation.
Delete the F curves.
Go back to orginal object and run animation
ERROR - there is no animation.
The data appears to be a single instance shared by the two objects. Editing one means editing both.
To get around this...
Go back to the point where you have separated and selected the new object
----Duplicate the separated object
Delete the first separated object but keep its duplicate
Go to f-curves and delete them for the dulicated object
(Now the data can be edited for the duplicate and is independent of the original object.)
Run animation
--the cube is animated.