A few thoughts...
The conflict: the words "Holophyly" and "Monophyly".
Originally, taxas of which all are from the same ancestor are "monophylitic groups", and out-groups are considerd another monophyly. Then came Henning with his Cladistics methods. In order to get his method to make sense, he took the word "monophyly" and applied a new defenition, meaning taxas that are composed of ALL the offspring of a common ancertor, including out-groups. Now with one word, two meanings, we have a confusion. Then along came Ashlock. In an attempt to clear things up, he tryed to replace Henning's "monophyly" with a new word, "holophyly". But, people started to use both words in cladistics; and we now have 2 overlaping words with 2 definitions, and a total of 3 combinations of word:definitions pairs.
Thanks a lot for messing stuff up, folks.
Notes: to find apomorphic charactors.
1.Out group comparison
If one of two homologous characters that occur as variants within a single holophyletic or monophyletie group is also found in the sister group, it is the plesiomorphic character.Any character that is restricted to the monophyletic group is apomorphic. A paraphyletic group is a monophyletic taxon which does not include all the derived ex-groups.
2. Ontogenetic sequence~ development.
3. Stratigraphic sequence~ fossil record.
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Autapomorpeic characters evolved in only one of two sister groups.~ignored in cladistics.
How did Mayr wrote this chapter?
Introduced the Cladistics method with detail with 10 pages; told the advantages and usages of cladistics in half a page; then used up a total of 20 pages bashing the method and the supporters of cladistics altogether as if they are all useless unreasonable junk.
He even used emotional phrases such as "..., so be it."
Boy, he really hates the new kids in town...
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