Question

What is an Outgroup?

Answer 1

Hint: It helps in the study of the phylogenetics or the cladistics that tells the evolutionary relationships between various organisms. It also helps in studying the differences and similarities among different organisms.

Complete answer:
An outgroup is a part of the cladistics that give the relationship between the distantly related organisms and will act as the reference group for determining the evolutionary relationships between the other related groups that are called the ingroups. The outgroups in general language are referred to as those groups in which the peoples do not belong and feel like an outcast. In biology, it is related to the group that does not belong to the clade but is related to the clade closely. The members of the clade are called in-groups and are more closely related in comparison to the outgroups that are less closely related.

Additional information
A phylogeny is a group of the evolutionary history of genetically similar organisms composed of ancestor species and descendant species. It gives the order and sequences of ancestors and their descendants. It is represented by a phylogenetic tree which gives the phylogenetic relationship between the organisms and their ancestors.
The phylogenetic trees are of different patterns thus forming various shapes and styles. The tree consists of various branches that indicate various subgroups and their common ancestor is at the bottom where the common point is marked. The longer and older phylogeny will have many branches while the shorter and younger ones will have fewer branches. It helps in determining the ancestry of both younger and older individuals.

Note:
Cladistics was first developed in 1950 by Wili Henning and is the most common method of incorporating information into phylogenetic trees. This method was accepted widely and is used commonly. From the term clade, the word Cladogram was derived. The events occurring on the earth can be studied with the help of the geological time scale and is named the ‘Earth’s calendar’.