AMNIOTE PHYLOGENY AND THE IMPORTANCE OF FOSSILS

摘要: Abstract— Several prominent cladists have questioned the importance of fossils in phylogenctic inference, and it is becoming increasingly popular to simply fit extinct forms, if they are considered at all, a cladogram Recent taxa. Gardiner's (1982) Lovtrup's (1985) study amniote phylogeny exemplifies this differential treatment, we focused on that group organisms test proposition cannot overturn theory relationships based only biota. Our parsimony analysis phylogeny, special knowledge contributed by being scrupulously avoided, led following best fitting classification, which similar novel hypothesis Gardiner published: (lepidosaurs (turtles (mammals (birds, crocodiles)))). However, adding resulted markedly different most parsimonious extant taxa: That classification like traditional hypothesis, provides better stratigraphic record. To isolate taxa responsible for latter data were successively partitioned with each phylogenetic analysis, concluded that: (1) ingroup, not outgroup, important; (2) synapsid, reptile, pivotal; (3) certain synapsid fossils, earliest or latest, responsible. The critical nature seemed lie particular combination primitive derived character slates exhibited. Classifying those along mammals, as sister lineage consisting birds crocodiles relatively poor data; one involving 2—4 fold increase evolutionary reversals! Thus, collectively individually, seems reside their relative primitive-ness, simplest explanation more conservative had less time evolve. While may be important inference under conditions, there no compelling reason prejudge contribution. We urge systematists evaluate fairly all available evidence.