To perform a segmentation click on the Mannequin and then on Bone segmentation.

Touch screen gesture: Press and hold on a bone to select it, then release. A green dot will appear. Repeat several times on the structure you want to keep. Then, swipe across some bones that you want to separate from the first. Tap on Cut.

Mouse interaction: Left click on a bone to select it. A green dot will appear. Move your mouse wheel one step to continue adding green dots on the structure you want to keep. Then add blue dots to the bones you want to separate from the first. Rotate the mouse wheel to adjust the color of the dot. Click on Cut.

The bones with blue dots will be separated from those with green.

Use the slider to bring back the separated bones and also to fade out the bones marked with green dots.