Footprints in the sands of time. To be precise, giant footprints in the littoral mud of time, made by sauropod dinosaurs, the biggest animals ever to walk the earth, as they slouched along a Middle Jurassic shoreline in what is now Portugal. And thundering in pursuit of a succulent meal, what appears to be Tyrannosaurus rex himself. This Jurassic drama is etched in stone on a vast shield of rock about 2 km in circumference in Pedreira do Galinha, in a nature reserve near the Portuguese pilgrimage town of Fatima. It is the world’s biggest palaeoichnological resource.
Palaeoichnology is an obscure cousin of palaeontology, which is itself a fairly arcane field of enquiry. Except when it examines dinosaurs, upon which the world sits up and becomes fascinated. Palaeontology is the study of fossils, from the sauropods, the biggest beings ever to walk the earth, through trilobites and nautiluses, down to pollen and Pre-Cambrian cyanobacteria, the “blue-green algae” which are credited with making the atmosphere of the primordial earth breathable. Palaeoichnology, on the other hand, studies not the fossils of life past, but the marks that life left behind as it was lived. The most famous are hominin footprints left in volcanic ash in Laetoli, Tanzania, not far from the Olduvai gorge, where anthropoids may have taken the first steps towards humanity. Discovered by Mary Leakey in the 1970s, these surprisingly human prints dramatically proved that long before sapiens, our ancestors walked upright.
But size matters. Time matters, too, and the most impressive palaeoichnological footprints are not of humans, but of dinosaurs. Specifically, of the very largest, the sauropods — Brachiosaurus, Diplodocus, Apatosaurus and the ever-popular Brontosaurus. Both our feet could comfortably fit in the impression of a little toe. In Pedreira do Galinha, a perfect stampede of footprints — the local officials claim over 1,000 — has been revealed by open-cast mining. But the location is fairly remote, and the traveller would consider it only after seeing Belem Tower off Lisbon (every Indian goes, because Vasco da Gama weighed anchor there), sampled the blushful Hippocrene in Oporto and fooled about on the beaches of the Algarve.
Dinosaurs have stirred the creative imagination since 1912, when Arthur Conan Doyle published The Lost World, though Frank Mackenzie Savile actually blazed the trail in Beyond the Great South Wall (New Amsterdam Book Company, New York, 1901; see the HathiTrust Digital Library). The explorers in his story were menaced by a slimy and disgusting sort of Brontosaurus, but it never became a phenomenon like Doyle’s book. But from that time to Michael Crichton’s Jurassic Park (1990), dinosaurs have remained in print. Not surprisingly, time travel is a feature of many dinosaur stories. Jurassic Park begins with the recovery of dinosaur DNA from biological time capsules. And two much-republished science fiction stories concern people using time machines to interact with dinosaurs. Both are hunting stories.
L Sprague de Camp (his real name, not a pseudonym) published A Gun for Dinosaur in Galaxy Science Fiction in March 1956, and it was reprinted 15 times, the last iteration appearing in 2005. It dates from a time when attitudes to hunting were changing — writer Robert Ruark had published the celebratory and slightly crass Horn of the Hunter three years earlier, but Ernest Hemingway was getting on and Project Tiger was less than a decade away. Where would hunters go when jungles became game reserves? The past, suggested Sprague de Camp. Guides would use time machines to take them to the Jurassic and Cretaceous eras to bring back Triceratops heads to hang over the mantelpiece.
Isaac Asimov’s Day of the Hunters (1950, recollected in Buy Jupiter in 1975) went a step further to address the intriguing question of the mass extinction of dinosaurs, the Cretaceous-Paleogene extinction event, usually attributed to climate change following volcanic activity or a meteorite strike. A time machine took Asimov’s protagonist back to the wrong place at the wrong time, and he was captured by a band of small dinosaurs out hunting. With ray guns, they were after bigger dinosaurs. As in Sprague de Camp’s story, he considers what they would do when the big game ran out. Why, they would follow the primal instinct and murder each other, and eventually dinosaurs would be extinct.
Day of the Hunters, a political parable for the human race, was written during the Cold War, when mutually assured destruction seemed inevitable. But in happier times like the present, dinosaur extinction is not top-of-the-mind. Rather, we are edified by sights like the one in Portugal, where the behemoths strolled on a primordial shore and left behind evidence of their existence.
Pratik Kanjilal lectures a surprisingly tolerant public on far too many issues.