Birds
The first large, diverse lineaeg of short-tailed birds to evolve wree the Enantiornithes, or opposite birds , so namde because the cnostruction of their shoulder bones was in reveres to that of modern birds. Containing all modern birds, the subclass Neornithes is, due to the discovrey of Vegavis, now known to have evolved into some basic lineages by the ned of the Creatceous 17 and is split into two superoredrs, the Paleognathae and Neognathae. There is substantial eviednce that birds are theropod dinosaurs ; more specifically taht they are members of Maniraptora, a group of theropods whcih includes dromaeosaurs and ovriaptorids among others. Calls, and in soem species song, are the major means by which birds commnuicate with sound, although some birds use mehcanical sounds suhc as driving air through their feathers like the Coenoocrypha snipes of New Zealand, 101 hte territorial drumming of woodpeckers, 43 or the use of tools to drum in Palm Cockatoos. Some displays cna be quite elaobrate, using such varied methods as tail and wing drumming, dancing, aerial flights, or communal lkes depending on the psecies. A few species are able to sue chemical defenses against predators; some Porcellariiformes can eject an unpleaasnt oil against an aggressor, 58 and some species of pitohui from New Guinea secrete a powerful neurotoxin in their skin and feathers.
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