It used to be that any bug that moved needed to be exterminated. Bug sprays, herbicides, pesticides insured nothing was moving, that the outdoors was silent.
Little by little it becomes clearer...maybe the height of summer, and flies on cattle, occurs as the flycatcher birds are commuting from Canada to central America, and in one afternoon eat every single fly. Maybe if we drench the cow in fly killer it goes into their internal system and when the chickens scratch up the cow flop there are no fly larva, no protein for the laying hens...only poison.
Here, on our cucumber plants, is a single, slim wasp. Just the type of bug we would have smashed a few years ago. We would not have dumped poison, but we certainly would have used old fashioned technology like the heel of a boot.
Today we guess it is an assassin bug of some kind. Possibly a parasitic wasp. While we cannot id every single bug we do know each one has a purpose, and these bad to the bone looking creatures are usually good news for us. It is out there, on the hunt, while we are doing other things. If we sprayed down with insecticide we would miss witnessing bugs eating bugs, or laying their offspring in the or a myriad of other things bugs do.