Here’s evidence that insects copulated 165 million years ago. It’s from this pair of Jurassic froghoppers, not much different from their modern forms.
Last week, announcing their discovery of the 165 million year old fossils, Shu Li et al wrote that “mating behaviours have been widely studied for extant insects. However, cases of mating individuals are particularly rare in the fossil record of insects, and most of them involved preservation in amber while only in rare cases found in compression fossils. This considerably limits our knowledge of mating position and genitalia orientation in the early insects, and hinders our understanding of the evolution of mating behaviors in this major component of modern ecosystems.”
More surprisingly, artists have also been reluctant to depict images of sexual union, and then often only of ambiguous behaviour. One example is the two-bear drinking fountain in the highly respectable playground of Kensington Gardens.
Meanwhile, the shapes formed by Henry Moore can be interpreted according to your own taste for things like these.
Shu Li’s fossil reveals a belly-to-belly mating position with the male’s aedeagus inserted into the female’s bursa copulatrix. The abdominal segments 8 to 9 of the male are disarticulated suggesting these segments were twisted and flexed during mating. The insects may have taken a side-by-side position, as in living froghoppers.