From similarity and differences of morphological, biochemical, cellular characteristics, biologist have constructed 'phylogenetic (evolutionary) trees' (who is most closely related to who, analogous to a family tree)
In the United States, lightning routinely kills more people each year than tornadoes or hurricanes. Tornadoes, hail, and wind gusts get the most attention, but only lightning can strike outside the storm itself. Lightning is the first thunderstorm hazard to arrive and the last to leave.
Even small thunderstorms are dangerous. Every thunderstorm produces lightning, which kills more people than tornadoes each year. Thunderstorms also cause heavy rain, flash flooding, hail, strong winds and tornadoes. When warm and cold air masses meet, a thunderstorm can grow.