>I disagree. "Branching of lineages" is clearly understood to mean that man descended from apes or other hominid types. "Common ancestors" is the supposed first organic unit which was able to replicate itself (with modifications of course). This may not be as explicit as you would like, but please remember that it was written in veiled terminology to not
overtly offend the people of Kansas. Or to put it more diplomatically, it was a compromise effort by people with varying interests. But the heart is alive and well.<
The split between humans and their closest relatives is but one example of branching of lineages. Branching of lineages can range from the split between eubacteria and archaebacteria plus eukaryotes to two siblings starting families.
Common ancestors likewise may likewise range from the common ancestors of all living things (which would include forms much more advanced than the first self-replicating organic units) to the common ancestry of individuals within a population.
> By adding this you cut out Sacculina and all of the tapeworms, as well as the fact that bacteria continue to exist.<
Sacculina and tapeworms are examples of parasites that have evolved through great reductions in morphological complexity. Xenoturbella, a nearly featureless worm that seems to be derived from the protobranch bivalves, is a non-parasitic example of evolution through simplification. Evolution is not a progression from simpler to more complex, but rather change over time, in whatever direction that takes. Bacteria have persisted rather than evolving into other forms because they are quite successful at what they do and have no urge or need to become something else. However, just because something is a bacterium does not mean that it is unchanged since the mid-Precambrian. Many have adaptations to more recent environments, e.g. inside modern organisms.
Dr. David Campbell
Old Seashells
46860 Hilton Dr #1113
Lexington Park MD 20653 USA
bivalve@mail.davidson.alumlink.com
That is Uncle Joe, taken in the masonic regalia of a Grand Exalted Periwinkle of the Mystic Order of Whelks-P.G. Wodehouse, Romance at Droigate Spa
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