Infraspecific molecular trees are associated with serial macroevolution in Pottiaceae (Bryophyta)

Abstract

The analytic orientation of this paper is intended as a replacement for the antiquated but still prevalent phylogenetic inferential models and techniques of the late 20 th сentury that are focused entirely on shared descent. Serial descent, that is, progenitor to descendant, may occur at the species or infraspecies level. In molecular systematics, species level paraphyly occurs when two examples of the same species are separated on a cladogram by a second species. This implies linear macroevolution of the second species from the first. Molecular cladograms often show cladistic structure (branching) among examples of the same species. If well-supported, such indicates a potential for evolution. A range of infraspecific and intraspecific cladistic structure in species of Pottiaceae (Bryophyta) was demonstrated in previously published molecular cladograms and data sets of other authors. This includes well-supported cladistic structure of molecular strains, and well-supported paraphyly involving other species. Large numbers of base pair changes among strains are considered here evidence of evolvability and increasing age of a species. Infraspecific strains are apparently lost in older species through speciation and extinction. Cluster analysis using DNA metadata of Oxystegus species matched published molecular cladograms to a large extent. The fact that apparent molecular strains are present in both nonparaphyletic and paraphyletic species, about half the species studied, shore up the theory that internal racial differentiation at the molecular level leads to or signals serial descent of multiple extant morphotaxa. It is because much infraspecific molecular cladistic structure exists that newly speciated taxa are already strongly cladistically dichotomized. Thus, the ultimate source of molecular paraphyly is internal to each species, and does not imply polyphyly by convergent species or cryptic taxa. Molecular systematics cannot effectively model progenitor-descendant radiation. Species with many strains are potential sources of future biological diversity. Recognition of differential evolvability may allow facilitation of complex, interactive, diverse ecosystems successfully tracking climate change.

A molecular approach to the phylogeny of the moss genus Pseudocrossidium (Pottiaceae, Bryopsida) and its taxonomic implications

“…According to Brummitt (2002), paraphyletic taxa are products of the evolutionary process, which is left behind as evolution moves on to a new level of organization. It is quite possible that considerable information may be obtained on evolution if paraphyly were ultimately recognized by phylogenetic systematists as informative of evolutionary direction (Zander, 2019b). The Pseudocrossidium adustum ‐ P. chilense lineage can be differentiated from the rest of the species of Pseudocrossidium by the slightly cucullate apex (Fig.…”

Running sigmas analysis of sampled molecular paraphyly in Pottiaceae (Bryophyta)

“…This paper investigates the evolutionary significance of reports of molecular paraphyly in previously published systematic studies of groups of mosses in the Pottiaceae of the Bryophyta by other authors. Here, the term paraphyly includes short-distance polyphyly, based on demonstration (Zander, 2019a(Zander, , 2019b) that branching molecular races of one progenitor species may separately generate descendant species creating a molecularly paraphyletic progenitor species. Statistical examination also demonstrated a clear congruence between use of morphological traits in macroevolutionary systematics and DNA traits in molecular studies, requiring only interpretation of results as speciesto-species trait transformation as radiation within a genus.…”

“…The Running Sigma spreadsheet is used here to evaluate the dispersion of values given in a metadata study (Zander, 2019b) There were 27 instances of paraphyly, with some species occurring in different studies.…”