Term (from grch. taxis = order, nomos = law) for the classification into a hierarchical system. In biology, living organisms such as animals, plants and viruses are hierarchically divided and classified into groups (taxa) according to their natural relationship. The first attempts to do this were already made in antiquity, for example by the Greek naturalist Theophrastos (370-287 BC).
The Swedish botanist Carl von Linné (1707-1778) developed the foundations of modern taxonomy and introduced the concept of "species" into biological systematics. In 1735, he published the work "Fundamenta Botanica", in which he for the first time presented in detail his ideas for redesigning the foundations of botany. His official botanical author abbreviation is "L.". However, Linne's classification system did not yet include all the categories or levels that are common today. However, these are not always used for all plants or animals. The respective use simply depends on how complex the respective units are. The three main categories almost always mentioned in professional sources are family genus-species. Each category can also be broken down into "subspecies". Similarly, the last sublevel of a main category can be created as a "superlevel", which then stands above the next main category (superdiviso).
The term species is a basic category of biological taxonomy. However, the species is usually given together with the first mentioned genus - for example, in the case of humans as "Homo = human (genus) sapiens = rational (species)". However, a generally valid definition of the term has not yet been achieved. In biology there are at least three species concepts that lead to overlapping but not identical classifications. In the concepts commonly used today, the term species usually refers to a group of living organisms that have so many distinctive morphological (shape and form or changes in them in the course of their developmental history) or physiological characteristics in common that they can be considered distinguishable from any other group of living organisms.
According to another view, those organisms and their direct descendants belong to a species that (can) reproduce with each other naturally, producing fertile offspring. A third view limits the species concept to organisms that share an ecological niche within an ecosystem. Reproduction or cross-breeding between two different species/species is not possible in principle for genetic reasons, but in most cases it is possible in vines, such as the two species Vitis vinifera and Vitis labrusca. These so-called interspecific crossing results are then referred to as hybrids in common parlance, although strictly speaking crosses within a species (intraspecific) are also hybrids.
As a rule, it is not possible to cross between species of two different genera, but there are also genus hybrids in nature. This means that when assigning animals or plants to the respective stages, the possibility of reproduction has not always been consistently taken into account. In practice there are several systems that differ in detail, especially in zoology and botany. See the taxonomy system most frequently used for plants or grapevine under grapevine systematics.