Too Big to Walk. Brian J. Ford. Читать онлайн. Newlib. NEWLIB.NET

Автор: Brian J. Ford
Издательство: HarperCollins
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Жанр произведения: Биология
Год издания: 0
isbn: 9780008218911
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but Owen was an experienced anatomist and was certain this was wrong. In 1841 he decided the newly discovered fossils represented reptilian animals and he named the genus Cetiosaurus. He was only half right – although Owen had correctly determined that these were reptiles, he concluded they were swimming creatures, somewhat like plesiosaurs, which is why he coined the name cetiosaur from the Greek κήτειος (kèteios, sea-monster). Owen wanted to learn more, and one day late in 1841 he hastened to 15 Aldersgate Street, near St Paul’s Cathedral, to visit his colleague William Devonshire Saull, a businessman and an avid collector of antiquities. Saull had amassed a collection of 20,000 specimens (most of them antiquities from the Middle East) which he had carefully catalogued and labelled. Many were of geological specimens, and some – the important specimens that Owen wanted to inspect – were fossils. Saull was a long-standing friend of Mantell, and they had often exchanged specimens. Among the many relics Saull showed him, Owen picked up a piece of Iguanodon bone, and turned it over in his hands. He knew of the various other gigantic specimens that collectors had unearthed – Megalosaurus, Mosasaurus, his own Cetiosaurus – and was suddenly inspired. These were not just creatures from the past, reminders of now-extinct worlds populated by animals like those of the present day; Owen became convinced that these all belonged to a single great family of reptiles. He suddenly realized that they were different from all the other reptiles we knew. Whereas present-day lizards have sprawling legs that splay out either side, these giant reptiles had downward-pointing limbs that functioned like columns to support their weight on dry land. He speculated that dinosaurs might have been warm-blooded, and he noted that they had five vertebræ fused to form the pelvic girdle, which he knew was not the case with other reptiles. Later discoveries would show he wasn’t entirely correct (some dinosaurs have different numbers of fused sacral vertebræ), but he was right to recognize these as a new group of huge, extinct monsters. This was a crucial breakthrough, and Owen decided to announce his conclusions at the eleventh annual meeting of the British Association for the Advancement of Science.

      These bones of a young Iguanodon were excavated from Cowleaze Chine on the Isle of Wight and were included by Richard Owen in his monumental work A History of British Fossil Reptiles published by Cassells of London between 1849 and 1884.

      The presentation took place on August 2, 1841, on a grey, dank day in London. Owen was a tremendous draw; Cuvier had died in 1832 and Owen had now become Europe’s most renowned zoologist. He had lectured on fossil reptiles before, but this time was different – this was to be his announcement of an entire new class of gigantic reptiles. He began by courteously acknowledging the pioneering discoveries made by William Buckland and Gideon Mantell, both of whom he acknowledged with respect. Then he reviewed what was known about crocodiles, and their similarities to plesiosaurs. And then he moved on to the meat of the argument, and began by describing three genera that he was going to analyze in detail: the herbivorous Iguanodon, the carnivorous Megalosaurus and the armoured Hylæosaurus. These, he said, were different from anything alive. These, he told his audience, formed a distinctly new tribe. Gone was the notion that these were merely long-lost forms of animals that were similar to those still in existence; these were a form of life that nobody had ever seen. His audience was spellbound. So many people had accepted that they were ancient forms of crocodiles, or something similar, but Owen was adamant. Megalosaurus, he explained, was not a gigantic sprawling lizard, but a huge reptile that stood upright on powerful vertical legs. His new image of Iguanodon was of a great monster, standing tall on massive hindlimbs, and towering above the lesser beings that were dotted about its forest landscape. With his majestic prose and his own charismatic powers of oration, Owen had the audience entranced as he radically revised the previous size estimates published by his colleagues. Mantell, he said, had erred in scaling up the size of the limb bones of an iguana to an iguanodon, and reaching an overall length of 75 feet (23 metres). Far better was it to scale up the dimensions of each single vertebra. This posed a problem in knowing how many vertebræ there were in the backbone, for most of the skeletons had a spine that was far from complete. But his calculations worked well: he concluded that an iguanodon would have measured about 28 feet (8.5 metres) from nose to tail, a far more realistic figure that fits well with what we know today. Owen made mistakes of his own in his talk: he described Thecodontosaurus as a lizard, and Cetiosaurus as a crocodile, though we now know that both are sauropod dinosaurs. Sometime after the lecture, he coined a new taxonomic name to define the entire group. He resolved to call them Dinosauria, which he said would distinguish the entire ‘distinct tribe or sub-order of Saurian Reptiles’. The word came from the Greek δεινός (deinos, terrible, awesome) and the familiar σαῦρος (sauros, lizard). It is a curious term, in that dinosaurs are definitely reptiles but are certainly not lizards, nor are they descended from them. This new term Dinosauria first appeared in the Report on British Fossil Reptiles, published the year following Owen’s momentous lecture.49

      Throughout his speech, Owen adhered to a strictly creationist view. He was convinced that these creatures had been made by divine providence, and the anatomical peculiarities he observed were, he insisted, the sure sign of intelligent design. He remained obdurate in these opinions, and was strongly opposed to any idea of evolutionary progress. He discussed these matters with Charles Darwin on many occasions, and the two became friends for a while. But when Darwin published his Origin of Species in 1859, Owen was to write a scathing review that he published anonymously. In later years, there was strong animosity between the two. Others had certainly laid the groundwork for this great revelation of the dinosaurs, even though it was Owen who coined the name. To this day, he is heralded as their great discoverer. As the BBC put it, Richard Owen is ‘the man who invented the dinosaur’.

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       The Public Eruption

      Many major discoveries were made by forgotten pioneers. So many of the great dinosaurs we know from today’s museums – from Triceratops to Tyrannosaurus – were first unearthed in the U.S., and it is easy to lose sight of what went before. I have explained that dinosaur fossils were known thousands of years before we usually believe they were discovered. Now we can see that there were ideas, images and sculptures of dinosaurs that are far older than the science of palæontology, and it has become clear that curiosity about these massive monsters dates back long before the word ‘dinosaur’ was coined. Indeed, it may have surprised you to see that descriptions and images of fossils were being published in learned books back in the 1600s. Alongside the many men whose names we have encountered stand the women who played a crucial role. Remember that the first person systematically to discover and study prehistoric reptile fossils was a woman, as was the first individual to recognize the significance of a dinosaur tooth, and also the first person to draw perfect studies of fossil dinosaurs for publication. The contributions to mainstream science by women have been widely sidestepped in the past; now would be a good time to reinstate their crucial contributions.

      Although the dinosaurs are our theme, palæontologists in England were finding the fossilized remains of other plants and animals and recording them in detail long before dinosaurs were recognized. This research was far more extensive than we usually imagine, and it was captured in a book by John Morris that was published in 1845. Morris was born in 1810 in London and had been privately educated to become a pharmaceutical chemist, yet he became increasingly interested in fossils, and began to publish scientific papers on his discoveries. Morris was a man of prodigious energy and had a remarkable memory, but he disliked speaking in public and was not given easily to writing. His strong point, however, was his fastidious facility for cataloguing. In 1845 he published his greatest work, and one which is a forgotten landmark in palæontology: a comprehensive catalogue of all the British fossils. Morris was subsequently appointed Professor of Geology at University College, London, and was elected president of the Geologists’ Association in