Every creature lives in essential unity with itself except people. A chipmunk never has angst over being a chipmunk. This human confusion is a result of what we think of as consciousness. Precious beyond words, consciousness is also a frequent pain. It is one of the chief components of what makes us truly human.
All life desires unity.
All of life desires happiness. The truth is, most of life already lives in a unified state, and in this sense is already happy and contented just being whatever they are. Yet life also yearns. The tree yearns for the sun, the animal yearns for food or to mate. These descriptions are obvious anthropomorphisms, yet still accurate in that they point toward a deep on-going and absolute desire all creatures have.