Methods for determining phylogenetic trees

Methods for determining phylogenetic trees - Methods for...

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Methods for determining phylogenetic trees: Cladistics and numerical phylogenetics Of all clean birds ye shall eat. But these are they of which ye shall not eat: The eagle, and the ossifrage, and the ospray, And the glede, and the kite, and the vulture after his kind, And every raven after his kind, And the owl, and the night hawk, and the cuckow, and the hawk after his kind, The little owl, and the great owl, and the swan, And the pelican, and the gier eagle, and the cormorant, And the stork, and the heron after her kind, and the lapwing, and the bat . Deuteronomy 14:11-18, KJV If modern species have descended from ancestral ones in this tree-like, branching manner, it should be possible to infer the true historical tree that traces their paths of descent. Phylogenies have been inferred by biologists ever since Darwin first proposed that life was united by common descent over 140 years ago. Rigorous algorithmic methodologies for inferring phylogenetic trees have been in use for over the past 50 years. In 1950, taxonomist Willi Hennig proposed a method for determining phylogenetic trees based on morphology by classifying organisms according to their shared derived characters, which are called synapomorphies (Hennig 1966 ). This method, now called cladistics , does not assume genealogical relatedness a priori , since it can be used to classify anything in principle, even things like books, cars, or chairs that are obviously not genealogically related in a biological sense (Kitching et al. 1998 , Ch. 1, p. 26; ). Using firm evolutionary arguments, however, Hennig justified this method as the most appropriate classification technique for estimating evolutionary
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Methods for determining phylogenetic trees - Methods for...

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