| Gallery
| From the first dawn of life, all organic beings are found to resemble each other in descending degrees, so they can be classed in groups under groups. Charles Darwin, Origin of Species, Chapter 13 | |
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| Ephemeroptera: mayfly | Odonata: dragonfly; damselfly | Blattodea: cockroach |
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| Mantodea: mantid | Isoptera: termite | Plecoptera: stonefly |
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| Orthoptera: grasshoppers; crickets; katydids | Dermaptera: earwig | Phasmida: walking stick; walking leaf |
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| Psocoptera: Book and bark lice | Hemiptera: true bugs | Homoptera: Cicada; aphid; plant hopper; leaf hopper; spittlebugs; scale insects; mealy bugs |
| Coleoptera: beetles | Neuroptera: Lacewing; antlion; snakefly | Hymenoptera: ant; bee; wasp; sawfly |
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| Mecoptera: scorpian fly | Siphonoptera: flea | Diptera: fly; mosquito; gnat |
| Trichoptera: caddis fly | Lepidoptera: butterfly; moth | |