As the study of natural history grew, so did society's effort to classify human groups.
An example of demography is classifying groups of people according to the year they were born.
In science, the term "family" has come to be used as a means to classify groups of objects as being closely and exclusively related.
Central products are an important construction and can be used for instance to classify extraspecial groups.
Thus, it could not provide a satisfying way to classify ethnic groups, much less "races."
Ethnicity on the other hand is a system that classifies groups of people according to cultural, linguistic and historic criteria.
An example is , which classifies groups of order .
Fischer was able to classify 3-transposition groups that satisfy certain extra technical conditions.
This method required no pre-selection or filtering of invariantly expressing genes to classify groups as previously published.
Classifying diverse groups of closely related organisms that differ by very subtle differences is difficult using a cladistic approach.