Botany, you may be relieved to know, is not dead. True, many
scientific journals and university departments have abandoned the term
in favor of more modern-sounding substitutes, while AJB and its
Canadian counterpart resist such impulses, confident that their
standing is enhanced rather than tarnished by association with the
discipline’s deep history. The organisms that were traditionally
studied by botanists are, of course, far too diverse to characterize
with any single unifying concept, let alone a phylogenetic one. But
many of us see the value in considering—and teaching— these divergent
and convergent organisms alongside each other, not in spite of what we
know of their phylogenies, but because of it. And if we don’t
introduce the next generation of researchers to all those interesting
fringe groups, who will?
In this regard, Borntraeger Scientific Publishers appears to be
stepping up to the plate. Under the editorship of W. Frey, they have
resurrected the classic Syllabus of Plant Families, a systematic
survey of all “plant” groups that was published in 12 previous
editions from the nineteenth through the mid-twentieth century.
Unsurprisingly, the many authors who contribute to the present edition
apply contemporary biosystematic principles to the groups they cover,
based on the latest phylogenetic data. At the higher levels of
organization, however, the series quite selectively includes only
those major lineages that were traditionally included in the province
of botany: not only plants and eukaryotic algae, but also
cyanobacteria, fungi, slime molds, and stramenopile pseudofungi. That
in itself need not be problematic, but a contemporary botanist will
expect to see a reasonable principle of organization that effectively
highlights structural/functional trends against the broad backdrop of
phylogeny.
The present volume in the series is a modern treatment of the major
groups of eukaryotic algae, excluding the reds, with descriptions of
their component taxa down to family and principal genera. At so many
levels, classification has undergone major upheaval in the molecular
age, with many of the phenotypic themes that underlay previous
taxonomic schemes now shown to correspond poorly with gene-based
phylogenies. Individual chapters include many high-quality color
images and some electron micrographs of characteristic taxa, as well
as a number of informative drawings and diagrams. Not only in
biosystematics are forward steps taken. The “cyanelle” of the
Cercozoan Paulinella is finally recognized as a primary plastid,
independent in origin from that of the Archaeplastida, although the
author stops short of formally treating Paulinella in a new algal
group. The familiar Volvox is, for once, never referred to as a
“colony,” in long-overdue recognition that this organism meets all
basic criteria of multicellularity.
The chapters are authored by 13 different specialists who provide
treatments of specific groups: W. Hofbauer (Glaucocystophyta,
Eustigmatophyceae); H. Kawai & T. Nakayama (Cryptophyta, Haptophyta,
Dinophyta, some Heterokontophyta, Chlorarachniophyta, Euglenophyta);
E. J. Cox (Coscinodiscophyceae, Mediophyceae, Fragillariophyceae,
Bacillariophyceae); B. de Reviers, F. Rousseau & T. Silberfeld
(Phaeophyceae); J. Neustupa (Chlorophyta, some Streptophyta,
Trentepohliales); F. Leliaert, J. López-Bautista & O. de Clerck (most
Ulvophyceae); F. Leliaert (Palmophyllales); I. Blindow & M.
Schudack (Charophyceae). In assembling an authoritative team of
experts from linguistically diverse nations, it is to be expected that
the English prose of many authors, good as it may be, will inevitably
contain imperfections. Unfortunately, this volume appears to have
been produced without the assistance of a scientific copy editor
proficient in the language, resulting in the publication of a
considerable number of errors in spelling and grammar. In most cases,
they represent little more than distractions, but they do take some of
the polish off the otherwise high production standards.
Within each chapter, authors organize groups discussed in a
biosystematic framework, as expected. At the level of chapter order,
and volume organization, however, the intentions and vision of the
series/volume editor are far less clear. The present volume covers
all the eukaryotic algae, except for the Rhodophytes, which are
treated in a separate volume. Why? Perhaps due to practical
considerations, related to page limitations or author deadlines, but
no explanation is given in the introduction. Of the remaining groups
in the Archaeplastida, the Glaucophytes are treated at the beginning
of the book, but the Chlorophyta and Streptophyta are not covered
until last, after all the other eukaryote groups. And there, they are
treated in a section titled Organization type: “Green Algae” that also
includes the unrelated Chlorarachniophytes and Euglenophytes. Here, a
brief introduction summarizes the different origins of the plastids in
each case, but doesn’t get around to saying exactly what the unifying
principle is. It could only be plastid pigmentation, because there is
nothing these groups have in common structurally that could possibly
represent a common “organization type.” But then one wonders why
there is no corresponding category set up for the major clades that
have red alga–derived plastids and pigments. Since the series is all
about systems, the reader will want to understand the layout,
particularly where it diverges from phylogenetic schemes. Perhaps the
editor is merely following the organization of the last edition (not
seen by me), published in the 1950s. But that ought to be explained
somewhere, and justified in a contemporary context.
We find the plastid-containing stramenopiles (Heterokontophytes)
treated in the present volume, while their heterotrophic lineages
(Oomycetes, Labyrinthulids) are covered in a separate volume with the
true fungal “water molds” and the slime molds. That seems
justifiable, since those heterotrophic groups are most likely to be
considered and taught within the context of mycology. But the volume
that treats those molds also includes the cyanobacteria (ultimate
source of all plastids), which would be much more appropriately placed
in the present work among the eukaryotic algae. In short, while one
might make a case for any number of different schemes, we never quite
grasp the logic of how the series or this volume is organized. It
would be helpful to have in the preface or inside cover an overview
cladogram of the major “supergroups” of eukaryotes, with indications
of those clades treated in specific volumes. The individual chapters
make many of these connections, but no encompassing perspective is
presented for the series or for this volume. So if you’re hoping that
the reappearance of Engler’s Syllabus will help revitalize the
inclusive traditions of classical botany, you may be disappointed by
the lack of a clear rationale for the trans-phylogenetic
juxtapositions that it adopts. That said, there is unquestionably a
great deal of value to found in the individual chapters of this book,
which are, after all, its essence.
William B. Sanders, Florida Gulf Coast University
Originally published in Plant Science Bulletin 64(1), 2018. (C) 2018 Botanical Society of America. Reprinted with permission.