Anagenis

Anagenis is a term that appears in some scientific writings as a variant spelling of anagenesis, the evolutionary process in which change occurs within a single lineage without branching. In contemporary usage, anagenesis is the standard term, and Anagenis is not generally recognized as a separate concept.

There is no broadly recognized genus or taxon named Anagenis in major biological databases. If the name is encountered in taxonomy, it is often a misspelling, an outdated or unpublished name, or a very obscure reference. When used as a taxon, it should be verified against current catalogs and literature.

Anagenesis, the process sometimes associated with the term Anagenis, describes gradual morphological or genetic change within a lineage over time. It contrasts with cladogenesis, where a lineage splits to form multiple descendant lineages. In the fossil record, evidence for anagenesis is inferred when successive strata show continuity of characters without clear branching, though distinguishing it from stasis and gradual drift can be challenging.

Etymology: Anagenis derives from Greek roots ana- meaning up or again and genesis meaning origin. The form Anagenis appears in some older texts as a variant spelling; modern usage rarely treats it as a separate concept or taxon.