William Meiklejohn, of Green Island School, asks :-
Are any insects extinct?
Ewan Fordyce, a paleontologist at the University of Otago, responded.
The fossil record of insects shows that some major groups - or lineages - once thrived but have since gone extinct.
Fossils show that insects originated more than 400 million years ago, in Paleozoic times. Many early fossils are known, for example, from Carboniferous rocks associated with the great Northern Hemisphere coal forests. One important ancient group, the Paleodictyopteroidea, included several lineages of intriguing forms, some with coloured wings spanning up to 55 cm. These paleodictyopteroids disappeared in a global extinction at the end of Permian times, about 250 million years ago, while closely related dragonflies persisted to modern days.
Another example of insect extinction involves species of eusocial bees (eusocial bees are species in which many non-reproducing workers support a reproducing queen). Eusocial bees appeared in Cretaceous times, beyond 65 million years, and thus lived at the same time as dinosaurs. A study of eusocial bees from Baltic amber, dated from 45 million years (Eocene), showed an unexpectedly high diversity, with 38 species in several major lineages. Since that time, many species and lineages of eusocial bees have become extinct, leaving only a few today.
Did some lineages become extinct because more-aggressive close relatives displaced them, or did cooling over the last 40+ million years cause extinction? More broadly, the fossil record shows that extinction is inevitable for life on earth. A few species go extinct when they evolve into new species, but most species disappear without leaving descendants. The history of life on earth is long, while the history of individual species is short.