Check out the graphics in this article, the golden ratio-like relationships of the biomass of various kinds of living things. All animals totaled weigh less than all protists, which weigh much less than all fungi, which are in turn much less massive than plants.
And among animals, humans weigh less than our own livestock, but more than all wild mammals put together. Still, arthropods (insects, spiders, crustaceans) outweigh everyone.
On a run tonight, I found a dead butterfly and put it on a log to pick up again on my way back. By the time I returned it was covered with ants.