47 million years ago , nine pairs of tortoises of the extinct species Allaeochelys crassesculpta were fossilized while copulating . A team of German paleontologists has found his remains in the Messel sites, a disused quarry near Frankfurt (Germany), where there used to be a lake, and which was declared a World Heritage Site by UNESCO more than 30 years ago.
Everything points to the animals accidentally dying while mating because their skins absorbed harmful substances from the lake , probably produced either by volcanic gases or an uncontrolled proliferation of cyanobacteria ("bloom") in early summer. According to Walter Joyce, a co-author of the study published in the journal Biology Letters , many animals go into a trance state while copulating or laying eggs, and it is possible that these turtles simply did not discover that they entered poisoned waters until it was too late.
