Question

What is the definition of outgroup?

1) A group of organisms that are closely related to each other
2) A group of organisms that are believed to be ancestral
3) A group of organisms that are known to lie outside the ingroup
4) A group of organisms that are unrelated to each other

Answer 1

In biological terms, an outgroup is a group of organisms that are known to lie outside the ingroup, providing a point of reference in evolutionary studies.

Step-by-step explanation:

The definition of an outgroup in a biological context is option 3: A group of organisms that are known to lie outside the ingroup. An outgroup is essential in phylogenetic studies as it helps to understand the characteristics and evolutionary relationships of the ingroup by providing a point of reference. When constructing a phylogenetic tree, the outgroup serves as a benchmark to the clade comprised of the ingroup.

For example, if we consider sports teams, unions, and sororities as in-groups, then people who do not belong to any of these groups would be considered as part of the out-group.