Giant fossil penguins
Giant prehistoric penguins in Peru? It sounds more like something out of Hollywood than real science. But a researcher from North Carolina State University, along with colleagues in other countries, has shown that two new penguin species reached equatorial regions tens of millions of years earlier than was thought possible. What's more, this was when the earth was much warmer than it is now. Palaeontologist Dr. Julia Clarke is assistant professor of marine, earth and atmospheric sciences at NC State. She and her colleagues studied two newly discovered extinct species of penguins. Palaeontologists from Peru had found the new penguins' sites in 2005. Both new species lived on the south coast of Peru. The first is called Icadyptes salasi. These penguins stood 5 feet tall and lived about 36 million years ago. The second new species, Perudyptes devriesi, lived about 42 million years ago. It was roughly the same size as a living King Penguin (2.5- These new penguin fossils are among the most complete yet recovered. They call into question earlier hypotheses about penguin evolution and how penguin species moved from one part of the world to another. Scientists believed that penguins evolved in Antarctica and New Zealand. They later moved closer to the equator. This was thought to have happened about 10 million years ago - after the Earth had gone through a period of cooling (34 million years ago). Nowadays we think of penguins as adapted to life in cold countries, Clarke says. "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." These new species are the first fossils to show that penguins were already living near the equator when the Earth's climate changed dramatically. This happened when the extremely warm Palaeocene and Eocene epochs gave way to "icehouse" Earth and permanent polar icecaps. Penguins reached equatorial regions during this earlier warm period, these new fossils show. They also thrived there at that time: More species are now known from the new Peruvian sites than live there today. Clarke and her colleagues estimate that the two Peruvian species are the result of two different dispersal events. They reached this conclusion by comparing evolutionary relationships with the places other fossil penguins have been found. This showed that the ancestors of Perudyptes seem to have lived in Antarctica. Those of Icadyptes may have started out near New Zealand, say the scientists. The new penguin specimens are among the most complete yet discovered that show what early penguins looked like. Both have long narrow pointed beaks. This is thought to be an ancestral beak shape for all penguins. Perudyptes devriesi has a slightly longer beak than some living penguins. But the giant Icadyptes salasi has a much longer beak, with features not known in any extinct or living species. The beak is sharply pointed, almost spear- These fossils seem to contradict some of what we thought we knew about the relationship between penguins and climate. But Clarke warns against jumping to conclusions. We should not assume that because prehistoric penguins were not adapted to the cold, living penguins won't be 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." More help with words breed environment evolution fertile fossil individual permanent placental species tentative tissue typical What's it all about?
Topic for discussion, research or pupil presentations A) In the popular film Ice Age the intrepid heroes meet a whole army of dodos, the flightless bird that went extinct in the 17th century (not during the Ice Age at all but who's counting?). These are portrayed as hilariously stupid, headstrong and clumsy birds, which manage to extinguish themselves at every opportunity by crashing into each other, falling off cliffs into diving into molten lava. While this makes for entertaining episodes, it is very unfair on the poor old dodo and totally misrepresents why species do go extinct. For a start any animal as suicidally stupid as the dodos in this film wouldn't have evolved and survived in the first place. In Ice Age 2, Manny the mammoth believes himself to be the last of his kind - Working in groups, students should choose a bird or animal that is now extinct, such as the dodo, mammoth, sabre- The class should then try to find the feature common to all extinctions. B) An interesting twist on the above is an in- A nice aspect of the lesson is the following activity that aims to make the scientific method explicit in kids' minds: Before beginning the research, have students develop a hypothesis about why their animal did not become extinct. They should write their hypothesis on Part A of the sheet ... Students should base their hypotheses on the facts discussed during step 5, as well as the discussion about why dinosaurs became extinct. Below is a sample hypothesis explaining why coyotes might survive if conditions on Earth changed dramatically and other species were killed off. Tips for science class discussions and groupwork No 54 Many of our students are poor readers ... if they do not understand what they read, then school and reading simply become a source of frustration. I am teaching and coordinating our summer school program, which is primarily web based (LA and Math).
There is a ton of reading that these kids must do and many of them simply cannot do it - which is probably much of the reason they are in summer school to begin with. Being able to work one on one with these students has been an eye opening experience. This new perspective, coupled with what I am learning from the reading course [the Florida On line Reading Professional Development], is causing me to become passionate about the belief that we all (teachers) must accept the responsibility of helping all students become better readers, regardless of our particular content. Many of the students I have been working with this summer are also some of our biggest discipline problems, which may result from the overwhelming frustration they encounter every day.
Extract from an online forum of the National Science Teachers Association by Tina Annucci, Gamble Rogers Middle School, St Augustine, FL
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