Insects / Reptiles / Rodents

Insects (Insecta), also called notch animals or notches, are the most species-rich class of the arthropods (Arthropoda) and at the same time with absolute majority also the most species-rich class of the animals at all. Almost one million insect species have been scientifically described to date (925,000 according to Grimaldi/Engel 2005, 865,000 according to Nielsen/Mound 1997). This means that more than 60 percent of all described animal species are insects. According to various extrapolations, however, one reckons with a multiple, whereby millions of undiscovered species are still suspected, especially in the tropical rainforests. The first fossil record of insects dates back to the Devonian period, about 400 million years ago.

Reptiles or creepy-crawlies (taxon: Reptilia, lat. reptilis "creeping") are a differently defined group of tetrapods, which - depending on the systematics (class or clade) - includes different groups of amniotes. In the traditional view, the reptiles (Reptilia) are a class of vertebrates at the transition from the "lower" (Anamnia) to the "higher" vertebrates (mammals and birds). However, the modern view is that they are not a natural group as such, but a paraphyletic taxon because they do not contain all the descendants of their last common ancestor. The classical taxon Reptilia is therefore considered obsolete and is rarely used in zoological and paleontological systematics. Today, the taxon name mostly serves as an informal collective term for terrestrial vertebrates with similar morphology and physiology (see Characteristics). In this sense, 11,440 recent reptile species are currently distinguished.

Rodents (Rodentia) are an order of mammals (Mammalia). With about 2500 to 2600 species they represent about 40% of all mammal species and are therefore by far the most species-rich order of this group. At the same time, they are the group with the most new descriptions within mammals; between 2000 and 2017, at least 248 species were newly described or newly established within the order. They have a nearly worldwide distribution and have colonized a variety of different habitats. Very few rodents are widespread as cultivars or pets, but these shape the picture of the entire group. Many species, on the other hand, are poorly studied and have a very restricted range.