Insects like ants, beetles and bugs have managed to survive all over the world- even in Antarctica. There are a minimum of 850,000 known insects worldwide. These organisms evolved to be sturdy and adaptable that all except one (the Permian-Triassic) have survived many mass-extinctions. Here are the reasons how they manage to do it.
Firstly, they produce profuse numbers of offspring that need little or no care. For instance, the African driver ant lays 3 to 4 million eggs once in every 28 days.
Secondly, they are equipped with alarming defenses. For examples, the ironclad beetle has super-tough shell; the shore earwig possesses rotting-flesh odor; the puss caterpillar owns toxic spines; the bombardier beetle emits a minute bomb inside the mouth of the organism that tries to eat it; and the tarantula hawks and warrior wasps fiercely attack their disturbing predators.
Thirdly, they are known for their disguise mechanisms that allow them to catch their prey or avoid becoming a prey themselves. For instances, the orchid mantis stays like an orchid to lure its prey; and the lichen-colored katydid camouflages itself by hiding inside a host tree encrusted with lichen.