What would the world be like with no bugs?

Just a few off the top of my head…(and I’m not a scientist… I just took several years of high school biology and watched lots of Bill Nye :)

-Dead leaves, animal corpses, etc. would pile up so that you literally could not see the trees in the forest. There would still be bacteria and fungi to help stuff decompose, but insects play a major role in this.

-It would disrupt the entire food web in ways I can’t even fathom. Everything from fish to birds to lizards to monkeys eat insects. This might cause many species of animals to go extinct.

-OMG agriculture! The bees, which are responsibly for pollinating many human-food plants, are already dying (in the U.S.; I’m not sure about in other countries.) And insects pollinate many plants. Some plants can only be pollinated by insects, so they too would go extinct presumably.

I often find myself wondering why ticks and mosquitoes have to exist though…

A world without bats or birds :(

Depends.
Are we talking about a world where insects never existed? Life would have evolved differently, including humans, but everything would be fine and dandy.
Are we talking about all insects suddenly disappearing? Complete global ecosystem collapse and mass extinction of almost all higher animals and plants that require insects for pollination.

If there were no bugs, then probably something else would have evolved to take that niche. It’s an important niche. I think it represents a huge portion of biomass. Ants and termites alone are said to make up 20% of all biomass on the planet. Probably the vast majority of life wouldn’t exist if there were no bugs, and without bugs, none of the rest of life would exist, at least in its current form.

Fortunately, biology is inventive, and if there were no bugs, there would be something else. All would be well. Although we might not recognize ourselves.

Tragic! No birds, no fish, no frogs, no bats, no anteaters or other insect eating creatures. No pollination, no plants, no disease to keep mammal populations in check. No pretty Butterflies to enjoy, no cool Preying mantises to watch, no intriguing fuzzy little Caterpillars.

Bugs are awesome!

I think Flick said it best.

See @Coloma
Assuming you like birds, bats, and those other critters.
And yes all you people, I like birds, bats and those other critters.

Radically changed ecosystems would only allow a few hundred million people to survive.