Zander, R. H. 2019. Macroevolutionary Evaluation
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Zander, R. H. 2019. Macroevolutionary evaluation methods extended, consolidated, and exemplified with Anoectangium (Pottiaceae, Bryophyta) in North America and the Himalayas. Annals of the Missouri Botanical Garden 104: 324-338. The original paper is available through the Annals of the Missouri Botanical Garden. This version for distribution has the same content and pagination. ABSTRACT Methods of macroevolutionary systematics as recently modified are explained and applied to the genus Anoectangium Schw¨agr. (Pottiaceae) in hyperoceanic areas of coastal northwestern North America. It was revealed that this area harbored species like those reported for the Himalayan region of northern India. Keys are provided for North American and Himalayan species of the genus. A macroevolutionary analysis, detailed in the Methods section, distinguishes and gives relationships between the species. There is strong Bayesian support for progenitor-descendant pairs and lineages. Anoectangium thomsonii Mitt. is considered a synonym of A. aestivum (Hedw.) Mitt. Anoectangium crassinervium Mitt. is transferred to Molendoa Lindb., under a nomen novum with A. handelii Schiffn. as a synonym. Anoectangium incrassatum Broth., related to the Asian A. clarum Mitt., is reported as a well-characterized species from the West Indies. Anoectangium stracheyanum Mitt. is re-lectotypified. Distinctions between A. aestivum and A. euchloron (Schw¨agr.) Spruce in the New World are clarified. Causal explanations in systematics are equated with entropy maximization in Shannon information analysis in the context of serial descent. A Pleistocene species pump hypothesis is advanced to explain the stenomorphic populations of species of the genus in eastern North America. Key words: Alaska, Anoectangium, British Columbia, bryophyta, China, evolution, hyperoceanic, India, Pottiaceae, Shannon information. The discovery of the Asian (India, China) species, (Zander & Eckel, 2007), and South America (Cano & Anoectangium sikkimense M. N. Aziz & Vohra, Pottiaceae Jim´enez, 2013). This paper is a synopsis mainly focusing (Zander, 2017a), in Alaska, and the report of A. stracheya- on Anoectangium Schw¨agr. in coastal northwestern North num Mitt., previously known from Asia and eastern North America. Worldwide, about 40 species are accepted. America south through Mexico, Central America, and the Schofield and Crum (1972) have reviewed the exten- Andes, as new to Canada from British Columbia (Zander sive past literature on bryophyte disjunctions and areas & Eckel, 2017), prompted Olivia Lee at the University in hyperoceanic climates, which include, in the North, of British Columbia to segregate 40 specimens of the genus Britain and Norway, the Faroes, the Alps, the Hima- in the herbarium (UBC) as possible specimens of these layas, mountainous Japan and Taiwan, North Pacific species, and to send them to the author for further analysis. North America, and high mountain slopes in the Ha- Lee suggested that one specimen, Schofield 67663,was waiian Islands, and in the South, southern Australia and A. stracheyanum and new to Canada, which proved correct. southern South America. They discussed probabilities The specimen identifications are summarized in the sec- of long-distance dispersal and vicariance explanations tions on representative specimens examined, though for the disjunctions, and concluded that no one hypoth- the work proved to be more complex than expected. esis explains all known data. More recently, Schuster This article provides a chance to gather together in one (1983: 497, 535) mapped and discussed endemic spe- place the new methods used for macroevolutionary cies in the northwestern North American hyperoceanic analysis, such that future Methods sections need only area as exhibiting a Laurasian distribution pattern. reference this paper for basic techniques. Disjunctions involving the northwestern hyperoceanic The present paper helps complete knowledge of the species of Anoectangium are apparently included in his genus studied in its worldwide distribution (Zander, discussion of circum-Laurasian distributions dissected 1993), for Middle America (Zander, 1977), North America by Pleistocene events and survival in refugia. I am grateful to the Missouri Botanical Garden for continued support for this and similar research. I am also grateful to O. Lee, collections manager at UBC, for bringing significant specimens from British Columbia and Alaska to my attention. L. Briscoe, collections manager at NY, is thanked for loan of specimens. P. M. Eckel kindly provided the illustration. Three anonymous reviewers were also quite helpful. Missouri Botanical Garden, 4344 Shaw Blvd., St. Louis, Missouri 63110, U.S.A. [email protected] Volume 104, Number 2 Zander 325 2019 Macroevolutionary Evaluation with Anoectangium (Pottiaceae) in North America and the Himalayas There have been five Anoectangium species, A. Anoectangium specimens from the Mitten herbarium aestivum (Hedw.) Mitt., A. euchloron (Schw¨agr.) Spruce, at NY, including those of A. clarum Mitt., A. crassiner- A. handelii Schiffn., A. sikkimense M. N. Aziz & Vohra, vium Mitt., A. stracheyanum, and A. thomsonii Mitt. A and A. stracheyanum Mitt., reported for North America key (Key 1) to the species of eastern Asia and North (Zander, 1977, 2017a; Zander & Weber, 2005; Zander America using traits as combed from the east Asian & Eckel, 2007, 2017). Anoectangium euchloron was and American literature (particularly Lawton, 1971; treated by Zander and Eckel (2007) as A. aestivum, but Gangulee, 1972; Saito, 1975; Zander, 1977; Eddy, revision by Cano and Jim´enez (2013) has demonstrated 1991; Sharp et al., 1994; Li & Iwatsuki, 1997; Li et al., its distinction. Problems in identification of the speci- 2001; Allen, 2002; Aziz & Vohra, 2008; Cano & mens from UBC required examination of types of Asian Jim´enez, 2013) is as follows. KEY 1. KEY TO NORTH AMERICAN AND HIMALAYAN SPECIES OF ANOECTANGIUM WITH DISTINCTIONS AS EXTRACTED FROM THE LITERATURE 1a. Leaves blunt, costa subpercurrent to percurrent. 2a. Leaves 0.7–1.2 mm in length, costa percurrent, gemmae absent . A. euchloron (Schw¨agr.) Spruce 2b. Leaves 0.4–0.5 mm in length, costa ending 3 to 4 cells before apex, gemmae often present on rhizoids in leaf axils . ........................................A. handelii Schiffn. [5 Molendoa antiqua R. H. Zander] 1b. Leaves acute, costa percurrent or more commonly excurrent as a short or stout mucro. 3a. Leaves abruptly widened at base as a broad skirt, basal margins strongly crenulate-denticulate . ......... .................................................................... A. sikkimense M. N. Aziz & Vohra 3b. Leaves not or somewhat widened at base, basal margins entire. 4a. Leaves with a weak constriction at top of leaf base, leaves about as wide above as at leaf base . .......................................................................... A. stracheyanum Mitt. 4b. Leaves without a constriction at top of leaf base, leaves widest at middle or just below. 5a. Distal laminal cells very thick-walled, papillae distinct, separate . ...........A. clarum Mitt. 5b. Distal laminal cells usually thin-walled, papillae crowded and somewhat fused. 6a. Leaves 0.7–1.2 mm in length, costa subpercurrent or more commonly ending in a small apiculus ...............................................................A. aestivum (Hedw.) Mitt. 6b. Leaves 1.2–2.5 mm in length, costa commonly excurrent as a large apiculus or mucro . ........................................... A. thomsonii Mitt. [5 A. aestivum (Hedw.) Mitt.] METHODS extension its roots in intuitive taxonomy, is firmly rooted in scientific theory and philosophy. The most important The aim of macroevolutionary systematics is to de- aspects of these methods are as follows: crease the coding of hidden information (negentropy) about evolution. Its methods are often at odds with those 1. Neo-Husserlian bracketing—In philosophy, this re- of phylogenetics. Classical taxonomy, although in part quires reevaluating a group from scratch, while an intuitive art form based on long familiarity with the using past work as guidelines, not holy writ, in an range of variation in a taxon, is not magic. Special effort to largely eliminate bias, beliefs, and values scientific techniques used in this macroevolutionary (Zander, 2018: 167). Any revision follows this con- study—and doubtless in part unconsciously by all cept to a large extent. This is why two keys are taxonomists—are summarized here, and many are dis- presented here, to emphasize major differences in cussed in greater detail by Zander (2013, 2014, 2016, present and past species concepts. 2018) though scattered in this literature. These methods 2. Inverse problem solving—This is the positing of as well as some new ones are gathered here in simplified several different solutions that may clarify what form as a Methods section. the problem might be, then testing for the most Systematics is occasionally described as a descrip- effective, essentially the inverse problem-solving tive endeavor, lacking the rigor and clearly supported method in physics. A welter of information may be results of experimental science. Yet, systematics is addressed by induction through informed sorting within the purview of “quasi-experimental” science that reveals suggestions of causal connections. (Cook & Campbell, 1979), which details how to use Problems with theory can be addressed by brave naturally occurring control groups to infer valid results invention of new theory.