Bygone beasts: Beasts of Eden: Walking Whales, Dawn Horses, and other Enigmas of Mammal Evolution by David Rains Wallace. University of California Press, 2004. US$24.95, £16.95 hbk (327 pages) ISBN 0 520 23731 5

View Large Image | Download PowerPoint SlideWallace's book ties together in an interesting way many of the old chestnuts of vertebrate paleontological lore. As a unifying artifice, he depends heavily on Rudy Zallinger's murals in Yale's Peabody Museum, where the ghost of stuffy old O.C. Marsh of dinosaur and uintathere fame still roams. Zallinger's ‘walk through time’ murals have never really satisfied me. Besides the ‘Peaceable Kingdom’ artificiality of the scenes, the animals depicted seem too well fed, too clean, too frozen in their snapshots of unlikely juxtaposition in front of mandatory cinder cones. Nonetheless, Wallace has skillfully woven his tale around the Zallinger art, which serves as a backbone on which Wallace fleshes out his version of vertebrate paleontological history. His literary use of the Zallinger frescos succeeds, I think, in drawing us into deep time. George Simpson's wife Anne once asked him in my presence how many dimensions he saw in geological scenery? He replied, ‘four’, which seemed to surprise Anne. He went on to explain that paleontologists normally saw the usual two dimensions of pictures on a wall, a third where layers of rock disappeared underground only to pop up somewhere else and, of course a fourth, the history of how the scenery had come to be.Wallace retells the story of our progress in constructing evolutionary theory. Forever, it seems, there has been a struggle between those who seek comfort in dogma and those who are willing to grow intellectually. Evolutionary mechanisms have come and gone, from Adam and Eve to Punctuated Equilibria (‘Punk Eek’), from evolution without genetics to evolution with genetics. Not only did Darwin have no more than a dim glimpse of the world's fossils, but also he lacked any knowledge of genetics. In spite of the fact that DNA would not be a factor for another century, he grasped an electrifying amount. However, Darwin never did figure out how evolution could be creative. We are still learning how evolution works but, unfortunately, creationist dogma is still holding back intellectual growth among the general public.Napoleon Bonaparte is said to have stated: ‘History is fable agreed upon by historians’, although he seems to have stolen the quip from Voltaire; every time history gets rewritten, opportunities abound for new errors to get kneaded into the mix. Also a lot of true history gets weeded out, either because of an author's bias or because he or she simply didn't know of it. All too often, the true history, if there is such a thing, gets overridden by the proclamations of swashbuckling loudmouths, or by popularizers not in possession of the full facts. There is far more to the story of vertebrate paleontology than can be gleaned from the official records of great museums or universities, or the memories of just a few players. Great advances are often made quietly, without fanfare. The assembly of the huge Frick Collection and its impact on paleontology is one such saga not told by Wallace. There are many others.Paleontologically, the world has been explored in a series of stages. First, there was Europe, then other areas. Darwin lived too early to be able to ponder a decent fossil record. The Garden of Eden has moved since his day and, currently, Asia is taking most of the limelight. Darwin would be pleased at how at least part of the record has been filled in. Who knows: perhaps if Darwin were still around, he might even go for ‘Punk Eek’!When a new part of the world is explored, there is at first always little or even no evidence, as was the case in the 1920s, when only a single rhino tooth was known from Mongolia until Walter Granger and others got going. Just as Kowalevsky tried to decipher horse history on the basis of the European record alone, his successor phylogeneticists have tried to piece together a more detailed record of many vertebrate groups, but they have had to change their stories repeatedly as new data came in. That process will never really end. Darwin complained about the lack of a fossil record, but even today we still have to fill in huge gaps that are really out there, not just the great leaps of ‘Punk Eek’. ‘Punk Eek’ might explain some apparent evolutionary flowerings, such as that following the winnowing at the K–T clap of doom for unsheltered organisms, but there are still long gaps in the record where a bit of old-fashioned prospecting could do wonders. The Age of Exploration is far from over!My copy of Wallace's book is covered with remarks in curmudgeonous red ink, but I recommend it heartily for those wanting to know the current version of evolutionary historiography.