March of the giant penguinsJune 26, 2007Prehistoric equatorial penguins reached 5 feet in height Giant prehistoric penguins? In Peru? It sounds more like something out of Hollywood than science, but a researcher from North Carolina State University along with U.S., Peruvian and Argentine collaborators has shown that two heretofore undiscovered penguin species reached equatorial regions tens of millions of years earlier than expected and during a period when the earth was much warmer than it is now. Paleontologist Dr. Julia Clarke, assistant professor of marine, earth and atmospheric sciences at NC State with appointments at the North Carolina Museum of Natural Sciences and the American Museum of Natural History, and colleagues studied two newly discovered extinct species of penguins. Peruvian paleontologists discovered the new penguins' sites in 2005.
The research is published online the week of June in Proceedings of the National Academy of Sciences. It was funded by the National Science Foundation Office of International Science and Engineering and the National Geographic Society. The first of the new species, Icadyptes salasi, stood 5 feet tall and lived about 36 million years ago. The second new species, Perudyptes devriesi, lived about 42 million years ago, was approximately the same size as a living King Penguin (2 ˝ to 3 feet tall) and represents a very early part of penguin evolutionary history. Both of these species lived on the southern coast of Peru. These new penguin fossils are among the most complete yet recovered and call into question hypotheses about the timing and pattern of penguin evolution and expansion. Previous theories held that penguins probably evolved in high latitudes (Antarctica and New Zealand) and then moved into lower latitudes that are closer to the equator about 10 million years ago - long after significant global cooling that occurred about 34 million years ago. "We tend to think of penguins as being cold-adapted species," Clarke says, "even the small penguins in equatorial regions today, but the new fossils date back to one of the warmest periods in the last 65 million years of Earth's history. The evidence indicates that penguins reached low latitude regions more than 30 million years prior to our previous estimates." The new species are the first fossils to indicate a significant and diverse presence of penguins in equatorial areas during a period that predates one of the most important climatic shifts in Earth's history, the transition from extremely warm temperatures in the Paleocene and Eocene Epochs to the development of "icehouse" Earth conditions and permanent polar icecaps. Not only did penguins reach low latitudes during this warmer interval, but they thrived: more species are known from the new Peruvian localities than inhabit those regions today. By comparing the pattern of evolutionary relationships with the geographic distribution of other fossil penguins, Clarke and colleagues estimate that the two Peruvian species are the product of two separate dispersal events. The ancestors of Perudyptes appear to have inhabited Antarctica, while those of Icadyptes may have originated near New Zealand. The new penguin specimens are among the most complete yet discovered that show us what early penguins looked like. Both new species had long narrow pointed beaks - now believed to be an ancestral beak shape for all penguins. Perudyptes devriesi has a slightly longer beak than seen in some living penguins but the giant Icadyptes salasi exhibits a grossly elongated beak with features not known in any extinct or living species. This species' beak is sharply pointed, almost spear-like in appearance, and its neck is robustly built with strong muscle attachment sites. Icadyptes salasi is among the largest species of penguin yet described. Although these fossils seem to contradict some of what we think we know about the relationship between penguins and climate, Clarke cautions against assuming that just because prehistoric penguins may not have been cold-adapted, living penguins won't be negatively affected by climate change. "These Peruvian species are early branches off the penguin family tree, that are comparatively distant cousins of living penguins," Clarke says. "In addition, current global warming is occurring on a significantly shorter timescale. The data from these new fossil species cannot be used to argue that warming wouldn't negatively impact living penguins." North Carolina State University | |||||||||||||||||||||
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Related Penguins Current Events and Penguins News Articles Penguins setting off sirens over health of world's oceans Like the proverbial canary in the coal mine, penguins are sounding the alarm for potentially catastrophic changes in the world's oceans, and the culprit isn't only climate change, says a University of Washington conservation biologist. Human influences challenge penguin populations The ecology of penguins makes these iconic swimming and diving seabirds of the Southern Hemisphere unusually susceptible to environmental changes. Passports for penguins Ground-breaking technology that will enable biologists to identify and monitor large numbers of endangered animals, from butterflies to whales, without being captured, will be shown to the public for the first time at this year's Royal Society Summer Science exhibition [30 June to 3 July]. Tuatara, the fastest evolving animal In a study of New Zealand's "living dinosaur" the tuatara, evolutionary biologist, and ancient DNA expert, Professor David Lambert and his team from the Allan Wilson Centre for Molecular Ecology and Evolution recovered DNA sequences from the bones of ancient tuatara, which are up to 8000 years old. Satellite tracking will help answer questions about penguin travels University of Washington scientists will attach satellite tracking devices to the backs of six penguins that have been treated at two centers in northern Argentina after their feathers were fouled with oil. The birds will be released into the Atlantic Ocean and their movements traced using satellites and the Internet. Stray penguins probably reached northern waters by fishing boat Guy Demmert got quite a surprise when he hauled a fishing net into his boat off the coast of southeast Alaska in July 2002. There among the salmon, in living black and white, was a Humboldt penguin, thousands of miles from where any of its kind should have been. Want to monitor climate change? P-p-p-pick up a penguin! We are used to hearing about the effects of climate change in terms of unusual animal behaviour, such as altering patterns of fish and bird migration. Huddling and a drop in metabolism allow penguins to survive the South Pole cold March of the Penguins, the Oscar® winning documentary, showed how the emperor penguins endure their incubation and fast for four dark and bitterly cold months each year. The tight huddling among these South Pole penguins is a key energy-saving mechanism that allows them to endure their extremely harsh conditions. Volcanic blast likely killed and preserved juvenile fossil plesiosaur found in Antarctica Amid 70-mile-an-hour winds and freezing Antarctic conditions, an American-Argentine research team has recovered the well-preserved fossil skeleton of a juvenile plesiosaur-a marine reptile that swam the waters of the Southern Ocean roughly 70 million years ago. Global warming capable of sparking mass species extinctions The Earth could see massive waves of species extinctions around the world if global warming continues unabated, according to a new study published in the scientific journal Conservation Biology. More Penguins Current Events and Penguins News Articles |
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