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CRETACIC PARK FORGET TOURISTS; IT WAS DINOSAURS WHO ONCE RULED THE BEACHES OF THE WESTERN ALGARVE
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Inside Magazine No. 16 September / November 2011
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NATURAL HISTORY
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s we get to Salema beach and start walking towards the cliffs, Luis Azevedo Rodrigues points to the numerous seagull prints in the sand: “Here they are! These are dinosaur footprints.” Had I not remembered that birds are direct descendants of dinosaurs, I would’ve been fooled by the palaeontologist’s quirky sense of humour. A resident in Lagos and a Biology and Geology teacher at Gil Eanes School, Luis is a renowned doctor of Palaeontology who has worked for the Portuguese Natural History Museum, gone on excavation expeditions in the Argentinian Patagonia and studied several dinosaur collections in natural history museums across the world, including England, the US and China. In his native Portugal, Luis is undoubtedly the go-to expert for those who want to learn more about the dinosaur footprints in the council of Vila do Bispo, and he organises guided tours for up to 15 people that provide information on this amazing and practically unknown heritage. Located on the western side of Salema beach, on a plain-looking rock that seems more suited to be used as a beach 'pillow', lies an eight-footprint track made by ornithopods, a group of bipedal herbivorous dinosaurs. Due to the lack of signage and the fact that the footprints are not well defined, Luis explains that people often ask why scientists are convinced that
those marks were really made by dinosaurs: “This rock may have suffered changes due to erosion, but the odds of such a pattern [similar to dinosaur footprints] being formed are small. If we add to that the fact that we actually have a trail of prints and not an isolated mark, we see that the possibility of erosion causing the prints is very slim,” he says. At 120 million years old, the cliffs’ age also acts as proof of the prints’ authenticity, placing them in the Lower Cretaceous period. With Luis’s help, it becomes easy to identify the animal’s heel and its three fingers. “It’s most likely that this was a lagoon area with muddy soil and under the influence of the sea,” he says, adding that temperatures at the time were much higher, such as in a subtropical or even tropical climate. According to the palaeontologist, footprints have a few advantages when compared to fossil findings – although they don’t enable scientists to specify the species of the animal, only its group, they provide information about the dinosaur’s size, weight and speed. “We have basic formulas that allow us to calculate this data and we provide them to children during the tour, making maths more appealing to them.” Based on the size of the footprints, Luis explains that the ornithopods that once inhabited Salema measured 1.6 metres at the hip, weighed around three to four tons and moved at a speed of four to five kilometres an hour.
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Does this mean dinosaurs were slow? “Not exactly,” he replies. “They were moving on muddy soil, which is very good for preserving prints, but not for moving quickly.” But ornithopods weren’t the only dinosaurs to enjoy Salema during the Cretaceous. On the eastern side of the same beach, in an area only accessible during low tide, we find a tilted rock with clearer yet finer prints: they belong to therapods, a group of bipedal carnivorous dinosaurs. “These footprints were made by much smaller animals and they point in different directions. However, it doesn’t mean there was a group of animals; it could have been one dinosaur moving in several directions,” notes Luis. Discovered in the mid-'90s, these prints are part of a ‘geological package’ that also comprises a number of footprints found at Praia Santa beach (around 500 metres west from Salema) and Fóia do Carro beach. Whilst the latter are not accessible by foot and are thought to be the oldest footprints found in the Algarve to date – Luis says they are still being studied -, the prints at Praia Santa beach indicate the presence
of much larger herbivorous ornithopods, with a hip height of up to 2.5 metres. The clearest, largest and best-preserved prints, these are also more difficult to reach. It takes a long walk down a beautiful valley, with a few loose rocks under our feet to get there, but the journey is definitely worth it. Luis believes that these footprints, especially the most accessible ones in Salema, are extremely important for tourism and educational purposes. Not only do they allow palaeontologists to track the different kinds of dinosaurs that lived in Portugal, but they also enable people to see this wonderful natural heritage in its biological context. “When people are educated, they preserve their heritage and there is no doubt that the fascination surrounding dinosaurs is huge. To feel that dinosaurs lived here millions of years ago is amazing.” To book a guided tour (in English, Portuguese or Spanish) with Luis Azevedo Rodrigues, please email: visit.dinos@gmail.com or cienciaaonatural@gmail.com The Lagos Centre for Living Science also organises tours for schools (upon request).
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