DINOSAUR

By Guy de la Bédoyère

PALAEONTOLOGY AND ARCHAEOLOGY

There's no faster route to ignorance than specialising in one subject to the exclusion of everything else. Palaeontology - the study of ancient fossils - not only shares physical and scientific techniques with archaeology, but also has a part to play in uncovering world history as well as having a history of its own.

Finds of dinosaurs, and the much later early fossil mammals of the Cenozoic period, have played a part in world culture for far longer than you might think. Present-day palaeontology has much to tell us about how other modern disciplines treat their subject-matter, by trying to order and classify everything but struggling under the weight of new discoveries which challenge assumptions.

Palaeontology is also exceptional, and generous, in depending just as much on amateur discoveries as it does on professional finds. There's much for archaeologists to learn there too. And, like most subjects you've never looked at before, there are plenty of surprises to be found - especially about the things you already were interested in.

Specialising in subjects is a very popular modern habit. But, in the past experts tended to have a much wider appreciation of different disciplines. Few Romanists these days know much Latin, if any at all, and most are unaware of the references to fossils and giant bones in ancient literature.

You might think dinosaurs never cross with archaeology. If so, you'd be completely wrong. In autumn 2001 a Time Team show was filmed on the Isle of Wight, exploring a new Roman site close to the long-known Roman villa at Brading. Before the dig, I had spent several weeks in August 2001 driving in the Western United States, visiting dinosaur excavation sites and had developed an interest in the history of palaeontology and its effect on society.

IGUANODON

I realised that Brading, and the new site, are very close to the Yaverland beach on the south-east coast of the Isle of Wight. This is one of the few locations in the United Kingdom, and the whole Roman Empire, where dinosaur bones are easily found on the surface. Most belong to the early Cretaceous herbivore, Iguanodon (left), dating to about 125 million years ago.

What made this especially interesting is that one of the Brading mosaic floors (above) features some fantastic animals (two griffins, and a cock-headed man called Iao) beside a small hut with steps (left). Before, and during, our excavation at the new site I speculated on whether finds of vertebrae on the beach had stimulated the villa owner's interest in mythical animals, or reinforced his beliefs. There's no way of knowing but one of our new trenches yielded a fragment of Yaverland beach rock packed with fossil shells. Someone in ancient times had picked that up and brought it home as a curio.

Monster of Troy vase c. 560-540 BC. Heracles and Hesione confront the monster, said to have appeared on the coast near Troy. The monster is depicted in a manner clearly based on a fossil skull. Note the treatment of the eye with the sclerotic bone ring, characteristic of various dinosaur-period animals such as the mid-Triassic pterosaur Eudimorphodon, recorded as fossil finds in Italy, and the bipedal herbivore, Hypsilophodon, recorded on the Isle of Wight. The vase is at the Museum of Fine Arts, Boston.

I was fascinated to discover on my return after the dig that the subject is covered in glorious detail in Adrienne Mayor's The First Fossil Hunters (Princeton, 2000). The photo above comes from the cover of her book. Specifically, Mayor argues that the Cretaceous beak-jawed quadrupedal herbivore, Protoceratops, was the stimulus for the griffin legend. The animal's characteristic neck frill may have been the stimulus for the griffin's wings, while its beak is self-explanatory. Found in significant quantities in the Gobi desert, the remains of Protoceratops are easily recognisable and cannot have been missed in antiquity. Mayor cites numerous others instances of fossil finds, including early mammals, in ancient times quoted by authors such as the Roman natural historian Pliny the Elder and links them to myths and legends. I thoroughly recommend you read the book. It is a triumph for a multi-disciplinary approach - specialist disciplines are not always the way to find new answers to problems.

Fossil femur fragment from a Miocene (22.5- 6 million years BP) mastodon or rhinoceros, excavated in the Temple of Hera, Samos (matchbox for scale). Seventh century BC or earlier (from Adrienne Mayor's book, p. 184). This is just one instance of early mammal fossils found in Greek deposits of the 1st millennium BC.

ANCIENT AUTHORS

In his description of Egypt written in the mid-fifth century BC, Herodotus said he himself had seen 'shells on the hills' (ii.12). Later on in the same text, he mysteriously refers to his search for information on the 'flying snakes'. Near Buto in Arabia he came across their 'skeletons in incalculable numbers ... piled in heaps' (ii.75). Just what he was talking about is completely unknown. The Greek philosopher Aristotle (384-322 BC) wrote a treatise on the Parts of Animals, noting that the remains of shells and other organisms turned up in rocks. He thought they must be evidence for earlier life from a time when the world took a different form.

However, opinions differed. Theophrastus (374-287 BC) wrote about rocks but thought fossils were unlikely to be remains of life. During the reign of the Roman emperor Tiberius (AD14-37), a volcanic eruption in southern Italy exposed 'corpses of rather large sizes'. Local people were too scared to move them, but they sent the emperor a tooth which is reported to have been more than a foot long (over 30cm) and offered to have the rest of the body dug up. Tiberius decided it was religiously unacceptable to disturb the dead and so asked a geometrician called Pulcher to reconstruct the face on the basis of the tooth's proportions. The emperor looked at the result with interest and had the tooth sent back.

Not many years later, the Roman natural historian Pliny the Elder reported that back in 58BC a 'monster ... forty-foot [12 m] long with its ribs taller than those of an Indian elephant and a spine 18 inches [45 cm] thick' was brought to Rome. We have no way of knowing now what it was that Pliny recorded, or what Tiberius saw. But Pliny also reported the griffin legend, and described how the griffins guarded the gold in Scythia (vii.10).

CLASSIFYING DINOSAURS

At first sight there seem to be a bewildering number of different types of dinosaurs. In fact the broad classifications are fairly simple. During the Triassic period (about 230-195 million years ago) the Archosaurs (early reptiles) evolved into two basic strands. One group was the origin of today's crocodiles and alligators, distinguished in part by how they walk. The other was the Dinosauria, largely distinguished by legs rotated as ours are - this is called 'fully-improved' and allows bipedal walking.

The Dinosauria continued to evolve for the next millions of years. Few types existed for more than a few million years at any point within the Triassic (230-195 BP), the Jurassic (195-140 BP), and the Cretaceous (140-65 BP). But they belonged to two basic forms: the Saurischian (lizard-hipped) and the Ornithischian (bird-hipped). Don't be misled by the latter - they aren't the ancestors of birds but in the phenomenon of 'parallel evolution' they had hips which resemble modern birds.

Saurischian dinosaurs divide into two: the Sauropods (basically herbivorous quadrupeds like Brachiosaurus and Diplodocus; and the Theropods (carnivorous bipeds like Allosaurus, Edmontosaurus, and Tyrannosaurus). Modern birds are thought to have evolved from some of the Theropods.

Ornithischian dinosaurs were largely bipedal herbivores like Iguanodon and the Hadrosaur group, but also include the Ceratopian herbivorous quadrupeds like Triceratops and Protoceratops.

Large mammals belong to much more recent times. The mammoths, for example, proliferated around 30,000 years ago - the last dinosaurs died out more than180 times as long ago.

TIME TEAM IN MONTANA

The book Phil and Tony were using in Montana is Dinosaurs. The Ultimate Guide to Prehistoric Life, edited by Michael K. Brett-Surman. It's published by HarperCollins, ISBN 0-00-710084-1, and costs £17-99. It is extremely good and very well illustrated.

Hell Creek is in north-eastern Montana about 75 miles north-north-east of Miles City. It's a State Park and is open to visitors. The fossilising conditions here and in southern Alberta have produced some of the finest preserved specimens in the whole world. Generally speaking the rocks belong to the late Cretaceous. Further south in Wyoming, Utah and Colorado is the Morrison formation which is of Jurassic date.

CONTROVERSIES

Like most archaeology-related subjects, palaeontology is dependent on public interest and commercial support. This sometimes makes for uneasy relationships. Humans normally settle in accessible places. That means modern humans normally live in or close to places where ancient settlements are buried - Britain is the perfect example. Humans haven't been around that long either - settlements in north-western Europe is counted in tens of thousands of years, not millions. So, the world hasn't changed a huge amount (apart from the rise in sea level after the Ice Age). A lot of archaeology is therefore a) easily found, and b) easily threatened by modern settlement.

Dinosaurs lived in places which now bear no resemblance to their original appearance. Fossils are most easily formed in places where sediment was deposited on their remains - that usually means riverbanks or coasts. Today, those places can be halfway up a mountain, deep under the sea or in the middle of a desert. Dinosaur bones therefore turn up in a variety of accessible, or remote places. Since the subject began in the nineteenth century, palaeontology has been largely dependent on the amateur fossil hunter who reports his or her finds. But the relationship normally works well: responsible amateur collectors are encouraged by professionals. Important discoveries, like Baryonyx in Surrey in 1983, can then be professionally recovered.

This is a quotation from the Acknowledgements in The Palaeontological Association's excellent new book Dinosaurs of the Isle of Wight:

'Thanks must also go to the many volunteers and amateur collectors who have discovered dinosaur remains in the cliffs of the island ... without such enthusiasts, scientists would not have specimens to work on and museums would have no fossils to exhibit.'

But, there is no possible way that museums and scientific organisations could accommodate all the finds. Most dinosaur bones are found on their own, broken into small pieces. Very few are found 'articulated' with all or part of the rest of the skeleton - these are the ones the professionals and museums are really interested in.

Individual bones are of little use. The Hadrosaurs, for example, had many different species generally distinguished by their skulls. The rest of the skeleton hardly differs. Some museums often sell smaller surplus pieces: it helps provoke interest and - frankly - helps finance further study. Palaeontology, like archaeology, is a luxury of our time and not a necessity.

So, why not leave the fossils where they are? For the simple reason that 99% of dinosaur bones and other fossils are found lying on the surface where they have been weathered out. Leaving them where they are guarantees swift and total destruction by erosion. This is especially true of fossil sites in the UK like the Isle of Wight, and Lyme Regis.

But that's not an invitation to carte-blanche fossil-hunting. Irresponsible collection damages rock faces, makes places dangerous and ruins specimens. Worst of all, the fossils end up with no provenance. So ... The most useful thing to do when you find fossils is to buy reference books and start to learn about the fossils, and visit your local museum and national collections. Whatever you do, label every fossil you find with place, date and preferably the rock layer it came from. But concentrate on the weathered-out specimens - they might be lost forever if you don't collect them.

At the moment there is an explosion in new dinosaur finds - textbooks from as little as ten years ago are quite out of date - amateurs have a big part to play in this. Right now the first bones from a Sauropod found in the eastern part of the Isle of Wight are in the process of being discovered and notified this way. And, in Australia, a farmer has just discovered evidence for a similar beast in Winton, Queensland.

BOOKS

There are numerous books on dinosaurs. These are some of the best and most recent (I have copies of each and have read all of them):

Brett-Surman, M.K., (consultant editor), Dinosaurs. The Ultimate Guide to Prehistoric Life, HarperCollins, London 2000

Gardom, T., and Milner, A., The Natural History Museum Book of Dinosaurs, Carlton, 2001

Martill, D.M., and Naish, D., Dinosaurs of the Isle of Wight, The Palaeontological Association, London 2001-12-31

Walker, C., and Ward, D., Fossils, Dorling Kindersley Handbooks, London 2000

Weishampel, D., Dodson, P., and Osmolska, H., The Dinosauria, University of California Press, 1992

LINKS

There are many dinosaur sites on the Web. Some to start with are:

Take care with fossils over the web though. Some sites are a bit short on detail and expensive for what they offer. Make sure they offer an approval or return period. American fossils are most easily sought on (put 'dinosaur bone' into the search window) but shipping to the UK can easily cost £10-15. Sometimes the pieces are so cheap though it's worth it.