Why do scientists add new kingdoms

When Linnaeus first described his system, he named only two kingdoms — animals and plants. Today, scientists think there are at least five kingdoms — animals, plants, fungi, protists very simple organisms and monera bacteria.

Some scientists now support the idea of a sixth kingdom — viruses — but this is being contested and argued around the world. Below the kingdom is the phylum plural phyla. Within the animal kingdom, major phyla include chordata animals with a backbone , arthropoda includes insects and mollusca molluscs such as snails. Phyla have also been developed and reorganised since the original work by Linnaeus — as scientists discover more species, more categories and subcategories are put in place.

Each phylum is then divided into classes. Classes within the chordata phylum include mammalia mammals , reptilia reptiles and osteichthyes fish , among others. The class will then be subdivided into an order. Within the class mammalia, examples of an order include cetacea including whales and dolphins , carnivora carnivores , primates monkeys, apes and humans and chiroptera bats.

From the order, the organism will be classified into a family. Within the order of primates, families include hominidae great apes and humans , cercopithecidae old world monkeys such as baboons and hylobatidae gibbons and lesser apes. Finally, the classification will come to the genus plural genera and species. These are the names that are most commonly used to describe an organism.

One outstanding feature of the Linnean classification system is that two names are generally sufficient to differentiate from one organism to the next.

An example within the primate family is the genus Homo for all human species for example, Homo sapiens or Pongo for the genus of orangutan for example, Pongo abelii for the Sumatran orangutan or Pongo pygmaeus for the Bornean orangutan. While this system of classification has existed for over years, it is constantly evolving. It enables researchers to sequence large numbers of genes from just one cell. Gordon Lax , another graduate student in the Simpson lab and an expert on this method, explained that for hard-to-study organisms like hemimastigotes, single-cell transcriptomics can produce genetic data of a quality previously reserved for more abundant cells, making deeper genomic comparisons finally possible.

The team sequenced more than genes, and Laura Eme , now a postdoctoral researcher at Uppsala University, modeled how those genes evolved to infer a classification for hemimastigotes. Lab members were instead stunned to find that hemimastigotes fit nowhere on the tree. They represented their own distinct lineage apart from the other half-dozen super groups. To understand how evolutionarily distinct the hemimastigote lineage is, imagine the eukaryotic tree splayed out before you on the ground as a narrowing set of paths, which begin with places for all living groups of eukaryotes near your toes and converge far in the distance at our common ancestor.

Starting at our mammalian tip, walk down the path and back into history, past the fork where our lineage diverged from reptiles and birds, past the turnoffs for fishes, for starfish and for insects, and then farther still, beyond the split that separates us from fungi.

If you turn around and look back, all the diverse organisms you passed fall within just one of the six eukaryote supergroups. Hemimastigotes are still up ahead, in a supergroup of their own, on a path that nothing else occupies. Finding a lineage as distinct as hemimastigotes is still relatively rare. But if you go down a level or two on the hierarchy, to the mere kingdom level—the one that encompasses, say, all animals—you find that new major lineages are popping up about once a year.

It empowers researchers to glean usable DNA from single specimens. Another kind of sequencing, called metagenomics, could accelerate discovery even further. Researchers can now venture into the field, grab a sample of dirt from the trail or a biofilm from a deep-sea vent, and sequence everything in the sample. But for eukaryotes, which tend to have larger and more complicated genomes, metagenomics is a troublesomely broad way to sample.

Metagenomics can point to potential hot spots of unknown diversity, and deeper sequencing can make metagenomic data more meaningful. Therefore binomial means 'two name'. Human beings belong to the genus Homo, and our species is sapiens - so the scientific binomial name is Homo sapiens.

The binomial system is important because it allows scientists to accurately identify individual species across the world without needing to know the scientist's home language. The grouping of families was added to allow the large number of new species to be included in this system.

Linnaeus' original ideas have been adapted, but continued to be accepted and as new species are identified they can be fitted into the current classification system. Originally, Linnaeus couldn't distinguish between different types of organisms such as algae , lichens , fungi, mosses and ferns.

The inability to examine such organisms in detail made classifying of these organisms as different species difficult at that time. As more scientific equipment became available, it allowed scientists to examine organisms in more detail and note important features, such as cell structure. This allowed more divisions in the classification system to be created. The advancement of technology further helped to develop Linnaeus' classification system.

Linnaean system of classification Living organisms are classified into groups depending on their characteristics. Kingdoms The first division of living things in the classification system is to put them into one of five kingdoms.