Elements in group 16 want to bond with elements in group

oxygen, sulfur, selenium, tellurium, polonium, and ununhexium (O, S, Se, Te, Po, and Uuh, respectively)

Explanation:

i hope it helps all this are 6 valence from electron and form 2-iron.

crayfish have experienced something called tagmosis where some of the segments have merged, thus they have heteronomous metamerism. the difference of the earthworms and crayfish is that earthworms have somewhat called homonomous metamerism - each of the segments looks like every other segment.