BEN # 257

Adolf Ceska aceska at victoria.tc.ca
Thu Sep 21 03:08:12 EST 2000


BBBBB    EEEEEE   NN   N             ISSN 1188-603X
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BBBBB    EEEEE    NN N N             BOTANICAL
BB   B   EE       NN  NN             ELECTRONIC
BBBBB    EEEEEE   NN   N             NEWS

No. 257                              September 21, 2000

aceska at victoria.tc.ca                Victoria, B.C.
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 Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2
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BOTANY 2000 IN PORTLAND, OREGON
From: Thor Henrich [thenrich at home.com]

A  very large rock has been tossed into the placid pool of clas-
sical plant taxonomy. This article will  describe  the  implica-
tions  of the resulting wave on the palaeobotanical community at
large.

On August 6, 2000, I travelled with Adolf and Oluna  Ceska  from
Victoria  to  Portland,  Oregon,  to  attend  'Botany  2000, New
Frontiers in Botany', for the annual meetings  of  the  American
Bryological  and  Lichenological Society, American Fern Society,
American Society of Plant Taxonomists, International Association
of Plant Taxonomy, and the Botanical Society of  America.  As  a
member  of  the  Palaeontological Section of the latter group, I
was keen to attend  this  gathering  of  approximately  900  at-
tendees,  for  4  days  of  talks, poster sessions, and informal
meetings with current palaeobotanists. I divided my time  mainly
among  the  systematic  and  palaeobotanical  sessions,  which I
briefly report here (for more  info,  abstracts,  etc.  see  the
website: http://www.botany.org/bsa/portland).

The  'rock in the pool' was actually launched last summer (1999)
at the 16th International Congress held at the Missouri  Botani-
cal  Gardens  in St. Louis. Dubbed 'Deep Green' and with a grant
of $285,000 USD, 200 scientists  from  12  countries  confronted
classical  Linnaean  taxonomy  (where  all organisms are divided
into the standard taxa we  all  learned  in  school  -  kingdom,
phylum,  class,  order,  family,  genus,  species, mainly on the
basis of morphology), to replace it with  phylogenies  based  on
new  data,  involving  sequencing  of  DNA  and  other strategic
biomolecules, statistical analyses,  and  phylogenies  based  on
cladistics (construction of hypothetical 'phylogenetic trees' or
cladograms). See their website at:
http://ucjeps.herb.berkeley.edu/bryolab/greenplantpage.html

That  Botany  2000 was hit by a wave of tsunami proportions from
the 'Deep Green' rock is evidenced by the excitement observed in
the otherwise staid halls of Academe.  Using  sophisticated  lab
hardware,   complex  probability  theory,  and  ornate  computer
programming, otherwise impossible-to-handle  massive  data  sets
are  crunched  down  to  produce  the  modern  analog of the old
'family trees'. Called cladograms, these branching diagrams  are
read  left  to  right, to show increasing diversity and presumed
evolutionary pathways for the taxa under consideration. Reaction
to the new methodology has  been  swift,  from  "It's  moronic!"
(William  Berger,  Curator  of  Botany  for  the Field Museum in
Chicago), to "I think  it's  the  greatest  thing  since  sliced
bread."   (Michael  Donoghue,  Director  of  Herbarium,  Harvard
University). Some random notes from these sessions follow.

 1. Plants should be in not  one  but  three  'kingdoms'  (i.e.,
    clades), called red, green, and brown.
 2. Land  plants  are  most closely related to the alga, _Chara_
    (stonewort).
 3. Fungi are much more  related  to  animals,  than  to  higher
    plants.
 4. Existing  phylogenies  of  living  plants  may or may not be
    supported  by   cladistic   analyses.   While   some   older
    phylogenies  are  supported  by  the new techniques, it some
    cases new and unsuspected relationships are  discovered.  In
    birds,  for  example,  vultures  are more closely related to
    cranes, than to raptors (e.g., hawks).
 5. Mosses and liverworts  are  more  closely  related  to  each
    other, than to hornworts [see also BEN # 196].
 6. _Amborella_  is the most ancient living dicot. Native to New
    Caledonia in the Pacific,at present there is only one living
    specimen in the United States -  at  the  Arboretum  at  the
    University of California at Santa Cruz.
 7. The  ANITA clade is the most basal for the angiosperms. A is
    for _Amborella_, N is for Nymphales (water  lillies),  I  is
    for  _Illicium_  (Chinese  Star Anise), T is for _Trimenia_,
    and A is for _Austrobaileya_, all are sisters in  the  ANITA
    clade.
 8. Monocots  seem  to  lie above the ANITA clade, but below the
    Eudicots (all the rest of the dicots above ANITA).
 9. Magnolids, long postulated to be the basal  group,  are  now
    placed  at  the  bottom of the Eudicots, still low but above
    ANITA.
10. _Acorus_ is sister clade to all monocots.
11. _Calycanthus_ (spice bush) is very closely related  to  _Um-
    bellaria_ (California bay).
12. Legumes  show highest diversity in the tropics of Africa and
    South America. Most North American legumes are derived  from
    European origins.
13. If  an  island  is  continental (not oceanic), tropical (not
    temperate), and emergent through the Tertiary, it will  show
    high rates of endemism.
14. Morphological  stasis  may  be  associated with species with
    disjunct distributions (e.g., _Liriodendron_).
15. North American plants show both stasis and rapid  evolution.
    Adaptive  radiations  appear  to  arrive  in  pulses  (i.e.,
    discontinuous).

Cladistic phylogeny is attempting to integrate data from classi-
cal morphology, biochemistry, and  palaeobotanical  sources.  An
interesting  first,  as  an example: a group of researchers have
been able to extract 'geolipids', in this case  terpenoids  from
Miocene (_Clarkia_ Flora of Idaho) fossil leaf and cone material
from  five different fossil conifers (_Metasequoia_, _Taxodium_,
_Cunninghamia_,  _Glyptostrobus_,  and  _Calocedrus_),  compared
them  to  their  modern counterparts, and found significant dif-
ferences which can distinguish the genera from  each  other,  as
well  as  demonstrate  degrees  of interrelationship. If the new
system of cladistic phylogeny becomes widely  adopted,  the  old
Rules   of   Binomial  Nomenclature  will  be  replaced  by  the
PhyloCode, with a new set of  rules  based  on  cladistics  (see
http://www.ohiou.edu/phylocode).

An  interesting and well organized treatment of this information
can be found on the website:
http:// www.ucmp.berkeley.edu/exhibit/phylogeny.html
and is highly recommended to the reader who wishes to learn more
about this new and rapidly emerging branch of bioscience.


PLANTS AND GEOLOGY: PIONEERING WORK OF FRANZ UNGER
From: Arthur R. Kruckeberg [ark at u.washington.edu]

The many linkages between terrestrial higher plants and  geology
have  a  long  and  colorful  history. The first real scientific
contributions were made during the first part of the  19th  cen-
tury.  Primacy  goes to Alexander von Humboldt who described the
effects of altitude on plant  life  during  his  tour  of  Andes
(Humboldt,  1805).  Goran Wahlenberg (1814), in his flora of the
Carpathians, noted effects of geology on plant distribution. But
the most notable contribution was made by  Franz  Unger  (1836).
What  follows on Unger is an excerpt from a new book in press by
Art Kruckeberg, _Plant and Geology - A Global View_ (Kruckeberg,
2001).

It is to Franz Unger (1836) that we turn for a  full-blown  con-
ceptualization  of  the  geology/plant  connection. Unger (1800-
1870) had a long and productive career in plant science; he made
influential contribution to the growing  science  of  botany  in
areas of cell biology, anatomy and morphology, palaeobotany, and
plant  pathology.  But  his  earliest adventures with plant life
were ecological. In that great 19th century encyclopaedic  work,
_The Natural History of Plants_, Anton Kerner von Marilaun gives
us  a vivid picture of the patterning of vegetation by substrate
that set Unger to develop his chemical  concept  of  plant  dis-
tribution. I quote at length from this picturesque account, from
the  English version, volume 2 (Kerner and Oliver 1902, pp. 495-
496):
   "The little town of Kitzbuhel, in the Northeast Tyrol, has
   a very remarkable position. On the north rises the Wild or
   Vorder Kaiser, a limestone chain of mountains with  steep,
   pale,  furrowed  sides,  and  on the south the Rettenstein
   group, a chain of dark slate mountains  whose  slopes  are
   clothed  far  up  with  a  green  covering.  The  contrast
   presented by the landscape in its main features is also to
   be seen in the vegetation of these two mountain chains. On
   the limestone may be seen patches of turf composed of  low
   stiff   Sedges,   Saxifrages  whose  formal  rosettes  and
   cushions overgrow the  ledges  and  steps  of  the  rugged
   limestone,  the  yellow-flowered  Rhododendron, and white-
   flowered Cinquefoil adorning the gullies, dark  groups  of
   Mountain  Pines  bordered  with bushes of Alpine Rose; and
   opposed to these on the slate  mountains  are  carpets  of
   thick  turf  composed  of  the  Mat-grasses sprinkled with
   Bell-flowers,  _Arnica  montana_  and  other   Composites,
   groups  of  Alpine  Alder  and bushes of the rust-coloured
   Alpine Rose -  these  are  the  contrasts  in  the  plant-
   covering  which  would strike even a cursory observer, and
   would lead a naturalist to ask what could  have  been  the
   cause.  No  wonder  that  the enthusiastic botanist, Franz
   Unger, was fascinated by this remarkable phenomenon in the
   vegetable world. In his thirtieth year, furnished  with  a
   comprehensive  scientific training, he came as a doctor to
   Kitzbuhel, and with youthful ardour he used every hour  of
   leisure  from his professional duties in the investigation
   of the geological, climatic and  botanical  conditions  of
   his  new  locality,  devoting his fullest attention to the
   relations between the plants and the rocks  forming  their
   substratum.  The  result  of  his study was his work, pub-
   lished in 1836, _On the Influence of Soil on the Distribu-
   tion of Plants as shown in the Vegetation of the Northeast
   Tyrol_, which marked an epoch in questions of  this  sort.
   The   terminology  introduced  in  the  book  found  rapid
   entrance into the  botanical  works  of  the  time.  Unger
   divided  the  plants  of the district accordingly to their
   occurrence on one or other of the substratums -- in  which
   lime  and  silica  respectively  predominated  -- into (1)
   those which grow and flourish on limestone only; (2) those
   which prefer limestone,  but  which  will  grow  on  other
   soils;  (3)  those which grow and flourish on silica only;
   and (4) those which, whilst preferring silica,  will  grow
   on other soils."

The essence of Unger's view -- that mineral content of rocks and
soils is the major edaphic influence on substrate-specific plant
distribution  --  has  been substantiated over and over again in
modern times. Unger's attempt to quantify the mineral nature  of
the  substrate  differences,  was to carry out analyses of ashed
plant parts. As Kerner pointed out, this  approach  failed,  but
the  key  concept  of mineral differences remains viable. Kerner
became a disciple of Unger's ecological ideas  and  carried  out
transplant  and  pot  test studies on species from limestone and
siliceous rock habitats. He explained  the  plant  responses  as
follows (Kerner and 0liver 1903, p. 498):

   "The difference in the vegetation on the closely adjoining
   limestone  and  slate  mountains  ... can be accounted for
   most satisfactorily in the following  way.  Plant  species
   which  demand  or  prefer a siliceous soil are absent from
   limestone mountains wherever their roots would be  exposed
   to  more  free  lime  than  is beneficial; if present they
   would be weakened, and thus  vanquished  in  the  struggle
   with their fellows, to whom the larger quantity of lime is
   harmless,  and  they would eventually perish. These plants
   flourish luxuriantly, however, on slate mountains  because
   there  the  soil  does  not contain an injurious amount of
   lime. The absence  of  species,  demanding  or  preferring
   lime,  from  slate  mountains can be explained in the same
   way."

It is curious to note that Unger's earliest work,  cited  above,
is not considered by botanical historians as his major contribu-
tion.  Besides being the co-author (with Endlicher) of a popular
botany text, Unger made major contributions in palaeobotany  and
historical  plant  geography, as well as in plant anatomy, plant
pathology and cell theory. His stand in debate with Schleiden on
cell division has been upheld and his ideas on evolution, though
attacked by the clergy of the day,  presaged  some  of  Darwin's
ideas.  Interestingly,  Unger  was a teacher of Gregor Mendel in
Vienna. "Unger's involvement in the  working  out  of  the  cell
theory and its application to the fertilization process may well
have played a crucial role in equipping Mendel for the cytologi-
cal  interpretation of his breeding experiments" (_Dictionary of
Scientific Biography_ 1978, p. 542).

Unger appears to  have  pioneered  the  "Chemical  Soil  Theory"
(Braun-Blanquet,  1932)  which  asserts  that the inorganic con-
stituents of the parent rock and derived soil strongly influence
the response of plants. It was  not  unexpected,  then,  that  a
contrasting  "Physical  Soil  Theory" would emerge. It belittled
the chemical effects and emphasized the importance  of  physical
properties (texture, particle size, porosity. etc.) in determin-
ing the nature of plant responses. The first acclaimed proponent
of  the  Physical  Soil Theory was Jules Thurmann (1849). In his
_Essai  de  Phytostatique_  Thurmann  emphasized  both  textural
differences  (psammitic  or coarse textured soils versus pelitic
or fine-grained  clayey  soils)  as  well  as  the  capacity  of
weathering  of  parent  rocks (eugeogenous rocks, high in silica
that weather readily versus dysgeogenous  rocks  like  Iimestone
and  chert  that  weather slowly). And so, in the mid-nineteenth
century a lively debate was joined; the two "hostile camps",  so
described   by   Braun-Blanquet  (1932),  kept  the  contrasting
theories in the air for the remainder of the 19th  century.  The
debate  continued  on to the time in the early 20th century when
soil science had acquired its major breakthrough,  discovery  of
the  colloidal  soil fraction and its role in cation exchange in
soils. From this salient discovery  (in  the  1920s)  and  other
influences,   adherence  to  either  the  chemical  or  physical
theories dissipated. It was then  realized  that  both  sets  of
factors  are  complexly interactive to yield a particular plant-
soil system.

References

Braun-Blanquet, J. 1932. _Plant Sociology - The Study  of  Plant
   Communities_.  McGraw-Hill, New York, NY (1965 English trans-
   lation)
Humboldt, A., von. 1805. _Essai sur la geographie des  plantes_.
   Levrault, Schoell et compagnie, Paris.
Kerner  von  Marilaun, A. & F.W. Oliver. 1902. _The Natural His-
   tory of Plants_. Blackie and Son, Ltd., London.
Kruckeberg, A. R. 2001. _Plant and Geology -  The  Manifold  Ef-
   fects of Land-forms and Lithology on Plants - A Global View_.
   University of Washington Press, Seattle, WA.
Thurman,  J. 1849. _Essai de phytostatique appliquee a la chaine
   du Jura_. Bern, Switzerland.
Unger, F. 1836. _Ueber der Einfluss  des  Bodens  auf  die  Ver-
   teilung  der  Gewaechse_.  Rohrmann  und  Schweigerd, Vienna.
   (N.B. The University of Washington Natural  Sciences  LIbrary
   has a copy of this rare work. - ARK)
Wahlenberg,  G.  1814. _Flora Carpatorum principalium_. Impensis
   Vandenhock et Ruprecht, Gottingae.


BEN ARCHIVE HAS A NEW SEARCH ENGINE
From: Scott Russell [srussell at ou.edu]

For  those  of  you  who  visit  the  BEN  archive  on  the  Web
(http://www.ou.edu/cas/botany-micro/ben/),  you  may  already be
familiar with a new full  text  search  engine,  implemented  to
search  old  issues  from  volume  115 (October 15, 1995) to the
present. This was implemented at  the  beginning  of  August.  A
convenient  input box is provided on the home page for a default
search of the site, which searches for all  terms  and  is  case
insensitive.  If  you like options, you will prefer visiting the
search page, which allows searches for an "exact phrase",  "all"
search  terms (which is the default) or "any" of the terms given
in a phrase. There is also an option for case-sensitive searches
or case-insensitive searches (the default) which may  be  useful
for finding specific terms. This is a "no-frills" search engine,
so  the  linked  BEN  issues  that  are  returned may need to be
searched by issue using the browser search key (in the edit menu
of your browser), which will jump from one term to the  next  in
the  document.  The  issues are arranged by number of "hits" for
the term and then by issue number.

Tables of Contents (listed on separate pages by  year)  and  the
alphabetical  subject  index  are still available on the site --
they are just augmented by the search engine. I wrote the search
engine because both tables of contents and indices are  horribly
inefficient  at  finding  data  that  the  writer, editor and/or
indexer did not recognize were useful at the time.

On another happy note, I was able to meet Adolf and Oluna  Ceska
for  the  first time, in person, during the Botany 2000 meetings
at Portland and share dinner. As you may  be  aware,  I  started
archiving  BEN with the same enthusiasm and foresight that Adolf
had, without even having met him  beforehand.  Our  meeting  has
been  duly documented with digital images on the Web. The images
are at
http://www.ou.edu/cas/botany-micro/ben/ceska.shtml

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