It was an important time of plate boundary rearrangement, in which the patterns of spreading centres and transform faults were changed, causing significant effects on oceanic and atmospheric circulation and temperature. Land connections existed between Antarctica and Australia, between North America and Europe through Greenland, and probably between North America and Asia through the Bering Strait.
It also had relatively low temperature gradients from pole to pole and high precipitation in a world that was essentially ice-free. The early Eocene (Ypresian) is thought to have had the highest mean annual temperatures of the entire Cenozoic Era, with temperatures about 30☌. The oldest known fossils of most of the modern orders of mammals appear in a brief period during the early Eocene and all were small, under 10 kg.īoth groups of modern ungulates, Artiodactyla and Perissodactyla, became prevalent mammals at this time, due to a major radiation between Europe and North America. The Eocene is the second of five epochs in the Tertiary Period - the second of three epochs in the Paleogene - and lasted from about 55.8 to 33.9 million years ago. The ornithologists therefore assume that the newly discovered species preferred a diet of fish, unlike modern albatrosses who primarily hunt for squid. 'The slender beak resembles that of modern seabirds that feed on fish,' he said. The avian skull examined by Mayr and his colleague Alan Tennyson differs from all other known albatross species not only in its size the shape of the beak deviates. 'Small albatross species are already known from the Eocene and Miocene epochs, but the new fossil is the youngest and most complete of these small forms and the only one of which a skull has been found.' Gerald Mayr of the Senckenberg Research Institute in Frankfurt. 'The new species we described is clearly smaller than all modern albatrosses,' said Dr. However, it presents the thorny issue of why the fish-eating species ultimately went extinct. Researchers studying the remains say that the find indicates a higher diversity in the feeding ecology of extinct albatrosses compared to extant species. Here, skull of the newly discovered albatross species (above) in comparison to the Antipodean Albatross, one of the largest extant albatrosses (below) Scientists have discovered an extinct albatross species from the Pliocene period after finding an complete albatross skulls.
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