Attention: If anyone knows advanced strategies for specific tier 10s, please let me know! I am making a separate guide for more advanced players! :D
Every animal (with the exception of the worm) has at least one boost bar. Boost bars are located at the bottom of the screen and can be filled by eating food. When eating food, the filled portion of the boost bar will be a light blue color. When the boost bar is filled, it becomes green. Eating food after filling up all boost bars will not affect them in any way. Animals can use their abilities by pressing or holding/releasing the space key or left mouse button(on computers) or by tapping the “Boost” button (on mobile). Animal abilities will usually use up one boost bar (with some exceptions).
On computers, you can also cancel a charged boost by pressing the right mouse button.