Integrating data from all continents and major biomes, we conservatively estimate 20 × 1015 (20 quadrillion) ants on Earth, with a total biomass of 12 megatons of dry carbon. This exceeds the combined biomass of wild birds and mammals and equals 20% of human biomass.
Because if there's anything worth getting scientific about, it's us vs the ant horde.
There are an estimated twenty quadrillion (20,000,000,000,000,000) ants in the world. They could wipe out all terrestrial life on earth if they wanted.
Easily ants. Google ant swarm animal. But not right before bed. There's a few insects that are evolved specifically to fight ants but everything else is food to them.
“Haha I will bite some of you! And then sit there doing that thing where I make a chewing motion with my tongue out and shake my head vigorously, because it isn’t working!”
You know those timelapse youtube videos where you watch ants eating a small fruit within a couple of days? Imagine that, but with it happening a lot faster with so many ants covering lions that you wouldn't be able to see them.
Another vote for ants, although that's partly because I'm a fan of the film Phase IV in which all ant species suddenly start cooperating with each other against humans.
Humans. Because the lions would be overwhelmed in short order after which the ants would kill each other off.
There are roughly 39,000 lions left in the world, none of which eat insects.
There are roughly 20 quadrillion ants on earth, a significant portion of which will eat live mammals, and almost all of which will kill any ant not from their own colony.