| Palaeos | |
Plants |
| Plants | Dendrograms |
Unit References |
Unit Dendrogram |
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Pieces |
In a refreshing departure from recent additions to our phylogenetic sections, the basic outline of plant evolution is rather well-known and stable. Nevertheless, we will be cautious, and build slowly. Imagine the embarassment should we err in drawing the tree of life for trees. In addition, botany seems to be unusually rich in thorny problems of nomenclature, with numerous synonyms which need to be weeded out, root and branch. Thus we will begin with a small kernel of higher level taxa and allow it to germinate slowly, as our ideas about plant taxonomy bear fruit in detailed coverage.
All tedious metaphores aside, we intend this section to be an experiment in setting up a rational scheme of taxonomy, without our usual fawning defference to definitions in the literature. To that end, we're going to vary the usual cladogram notation to explicitly state what kind of clade (or other taxon) is being noted. The scheme is as follows:
o : crown group
< : stem group
= : paraphyletic basal radiation
^ : apomorphy-based clade
* : similarity based classical taxon
? : basis not yet established
< Chlorobionta = Quercus > Gelidium
|--= Prasinophyta
`--o "Green algae" = Quercus + Chlamydomonas
|--< Chlorophyta = Chlamydomonas > Quercus
`--< Charophyta = Quercus > Chlamydomonas
|--* (various algal groups)
`--o Embryophyta = Quercus + moss
|--< Bryophyta = moss > Quercus
| |--* Sphagnum
| `--= "Andreaeids"
| |--< Polytrichales
| `--< Bryopsida
`--< Tracheophyta (= Pan-Tracheophyta Cantino & Donoghue 2007 = Polysporangiomorpha of Kenrick & Crane, 1997) = Quercus > moss
|--= various rhyniophytes (Rhynia, Cooksonia, etc.)
`--+--o Lycophytina = lycopsids (Huperzia) + zosterophylls (Sawdonia)
`--o Euphyllophyta = ferns & horsetails (Equisetum) + Quercus
|--< Monilophyta = Equisetum > Quercus
`--< Spermatophytata = Quercus > Equisetum
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