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- Most living birds today are classified into de modern bird (Neornithes) group.
- All modern birds lack teeth.
- All modern birds have a simple upper jaw, rather than the complex jaw of older birds like ostriches and kiwis.
- All modern birds have the basal bones of their feet fused, and a long third finger.
- All modern birds have hollow bones, to be lighter and to make flight easier.
- Most modern birds have a four chambered heart.
- Many social species pass on their knowledge across generations.
- They are highly social, communicating with visual signals, calls and songs.
- Most modern birds are monogamous, which means they only have one couple at a time, sometimes for life.
- Some modern birds have lost the ability to fly, since they live in places with no predators, for example the kakapo from New Zealand.
- Probably the most successful group are the Passerine (Perching birds) with 60% of all living bird species.
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| King Pengiuns; photo by Axinar, cc-by |
Spatula; photo by Amanderson2, cc-by |
Kingfisher; photo by Frank.Vassen, cc-by |
Sources:
-Assembling The Tree of Life, Joel Cracraft and Michael J. Donohue, 2004
-The Complete Dinosaur, Second Edition, M.K. Brett-Surman, Thomas R. Hotlz, Jr., James O. Farlow, Indiana University Press, 2012
Citation: García, A.I. 2015. The Tree Of Nature (Online) at http://thetreeofnature.com
