Predictivity vs Useful
kinman2 at YAHOO.COM
Tue Feb 15 10:43:40 CST 2005
Excellent examples. And flowering plants are another group (like Diptera) that arose relatively late (compared to crustaceans, molluscs, tetrapods, and so forth). And being far less dependent on fossil evidence, the predictivity is relatively high.
The further back in time you go (and therefore the higher the ranks of taxa you are dealing with), the more predictivity tends to be compromised (and problematic when pushed beyond its limits), and thus the more useful paraphyly becomes (on occasion). That's why I generally don't feel any great need for paraphyletic species, genera, or even families. There are exceptions though, the most obvious being the hominids (where scrappy fossils are again a huge problem, not to mention homoplasy).
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