Threatened arthropods and described. The total number of living arthropod species is probably in the tens of millions. One conservative estimate puts the number of arthropod species in tropical forests alone at six to nine million species. As a consequence of all of the above, most published estimates of the total number of endangered insects and arachnids are probably low by at least an order of magnitude. Conservatively at least eighty percent of all living animal species are arthropods. Since arthropods constitute the majority of the faunal biomass on Earth, their role is vital to the survival of large numbers of insectivores
Arthropods in film higher percentage of oxygen, arthropods would be able to grow quite a bit larger before their trachea became too large and could not grow any more. In fact, in the early years of the earth, when the atmosphere was more oxygen-rich, dragonflies the size of crows were not an uncommon sight. Winsor McCay, one of the founders of animation, made the first animated film about insects in 1912, titled "How a Mosquito Operates". In the early 20th century, it was technically easier to include insects in animated films, which are drawn, over live-action films which would require more advanced techniques