“Rationalists,” writes noted British paleontologist Richard Fortey, “are not permitted to have shrines,” but if they were, Shark Bay, on the remote and barren coast of Western Australia, “might be high on the list.” Shark Bay is the place where, in 1954, a form of life so ancient it makes one giddy to think of it was discovered alive and well in the clear, shallow waters of a cove known as Hamelin Pool.
Stromatolites, for those who have never heard of them, are dark brown columnar structures (some apparently look like knobbly cauliflower heads or even giant mushrooms) made up of layers of cyanobacteria, only the topmost of which is actually alive. They grow incredibly slowly, and look like something inorganic, though, as Fortey discovers, they are tacky to the touch. But what is really amazing about them is that structures almost identical to the ones now growing in Shark Bay can be found in the fossil record going back more than two billion years.
“Horseshoe Crabs and Velvet Worms’’ is the fascinating story of these “messengers from deep geological time.” From cyanobacteria to jellyfish and gingkos, the book traces the biology of a handful of animals and plants that have survived through eons of time. For reasons that may forever elude even the most imaginative biologists but that clearly have something to do with luck, certain archaic life forms have persisted through the heating and cooling of earth, the rising and falling of seas, the colliding and breaking up of continents, even a succession of mass extinctions, the most severe of which wiped out nine-tenths of all life on the planet.
Fortey, whose own field of interest is one of the creatures that didn’t make it — an ancient arthropod that swarmed the Palaeozoic seas and went extinct some 260 million years ago — is the author of several books, including “Trilobite!: Eyewitness to Evolution,” “Life: A Natural History of the First Four Billion Years of Life on Earth,” and the charmingly titled “Dry Storeroom No. 1: The Secret Life of the Natural History Museum.” A lively writer with a penchant for slightly goofy jokes, a vast storehouse of arcane knowledge, and an inexhaustible fund of enthusiasm for his subject, Fortey is the perfect interpreter and guide to the marvels and mysteries of archaic existence.
Here, the author sets himself the task of visiting the home of each of the “living fossils” he has chosen to represent a particular period of deep time. Thus, we travel with him to New Zealand to examine a segmented creature called the velvet worm (which turns out to be neither velvety nor exactly wormlike), as well as a lizard-like reptile known as the tuatara whose closest kin was last seen in the Triassic. We accompany him to the hot springs of Yellowstone, where he examines organisms even more archaic than those growing in the tepid West Australian seas, and up into the Sierra de Tramontana in Mallorca to look for something called a ferreret, aka the Mallorcan midwife toad.
Fortey’s descriptions of these places are charming little exercises in travel writing and constitute one of the great pleasures of the book. But he is also alive to the absurdities that crop up in the course of his quest. On a visit to blustery Newfoundland to examine some slabs of sediment laid down more than 500 million years ago, he notes a sign instructing visitors to “remove footwear before visiting fossil bearing surfaces.” “I confess,” he writes, “that the idea of taking off one’s boots in a howling squall to safeguard fossils that had survived since the Precambrian had its funny side.” Or, on learning that the lamprey was still to be found on the menu in Lithuania, he “trotted around the cobbled, sloping streets” of Vilnius, looking for a restaurant that served this primitive fish. He was met, he writes, with puzzled looks. “I suspect it was as if a Lithuanian had gone around London asking if eagle was on the bill of fare.”
But there is a serious side to the book as well. One of the curious effects of thinking about such tremendous spans of time is fatalism in the face of climate change and what biologists sometimes refer to as the “sixth mass extinction” — the one currently being perpetrated by human beings. Fortey counters this with a capacity for wonder that should shame anyone inclined to be blasé. “I did not know [the story of the Mallorcan midwife toad] before I went to Mallorca,” he writes, “and the chances are high that you did not know it either until you read this book.”
Every creature has a unique and fascinating life history, he argues. The horseshoe crab, the velvet worm, the lungfish, the aurochs are just the tip of the iceberg (as it were). There are still the “ricinuleid arachnids, which are neither spiders nor mites,” or “the primitive cactus Rhipsalis,” which despite being specialized for arid conditions may have originated in the damp forests of Gondwana. In a pitch to the 10-year-old fossil-collector trapped inside us all, Fortey cheerfully exhorts us to keep looking, for “[t]here is still so much to learn.”