@ARTICLE{Jadwiszczak_Piotr_Penguin_2009, author={Jadwiszczak, Piotr}, volume={vol. 30}, number={No 1}, journal={Polish Polar Research}, pages={3-28}, howpublished={online}, year={2009}, publisher={Polish Academy of Sciences}, publisher={Committee on Polar Research}, abstract={Penguins (Aves: Sphenisciformes) hold much interest for many people, including (but not limited to) scientists. According to results of molecular studies, penguin history began in the Cretaceous, but the oldest bones assigned to these birds are Paleocene in age. The first fossil representative of Sphenisciformes formally described was Palaeeudyptes antarcticus, and this event took place 150 years ago. Since that time, several dozens of species have been erected, though not all of them have stood a test of time. The 21st century entered new dynamics into the paleontology of penguins, and (importantly) it concerned both the new material, and new theories. This paper summarizes what we currently know about extinct penguins and indirectly suggests the most promising areas for further research.}, type={Article}, title={Penguin past: The current state of knowledge}, URL={http://journals.pan.pl/Content/110537/PDF-MASTER/PPR30-003.pdf}, keywords={Southern Hemisphere, Aves, Sphenisciformes, evolution, fossil record}, }