November 2010

Remarkable Creatures: Epic Adventures in the Search for the Origins of Species by Sean B. Carroll; Houghton Mifflin Harcourt, New York, 2009, $26.00, hard cover, 331 pp. Includes a nineteen page Index, a two page Acknowledgments section and a twenty-three page Sources for Further Reading section.

Important Contributors to Evolutionary Studies

Carroll is the author of Endless Forms Most Beautiful (reviewed here in October, 2006) and The Making of the Fittest (reviewed here March, 2007). With the release of Remarkable Creatures in 2009, Carroll continues to be one of the leading communicators of evolutionary science to the public. This latest offering is decidedly less technical than his previous books, both of which included some of the technical aspects of genetics.

Remarkable Creatures is a collection of adventure stories about the individuals who have contributed greatly to the discovery and understanding of evolution. Following an introductory chapter, the book is organized into three sections: Part 1, The Making of a Theory, Part 2, The Loveliest Bones, and Part 3, The Natural History of Humans. Each chapter within these sections presents an adventure story of sorts of an individual or individuals work that contributed toward the discovery, understanding or evidence for evolution. There are 13 chapters in all. Readers will be very familiar with many of the people in these chapters and will learn much about some of the less well-known contributors to evolutionary theory.

The introductory chapter is about the explorations of Alexander von Humboldt whose expeditions in previously unexplored regions in South and Central America became an inspiration to people like Poe and Jefferson (1). Humboldt's publications documented his journeys and discoveries about the natural world he encountered. His exploits and writings inspired many of the naturalists that followed him.

The first section of Remarkable Creatures, The Making of a Theory, begins with Charles Darwin as one might expect. While there is much familiar ground covered in this section, Carroll includes some lesser known background information about Darwin.

Following Darwin is a chapter on Alfred Wallace whose own work on speciation nearly eclipsed Darwin's. There has not been as much written about Wallace so this chapter has a lot to offer the reader. Wallace, like Humboldt, began his explorations in South America. His collections from this trip were extensive but the trip almost cost him his life as his ship caught fire and sank in the Atlantic on his return trip to England. After ten days adrift in a leaky lifeboat, Wallace and the crew were rescued but his collections had been lost. Undaunted, Wallace next set sail for Indonesia and the surrounding area where he continued his collections and observations. As Wallace traveled from Island to island he noticed a significant difference in some animal species from one island to another. He thought that this was unusual since the islands were in close proximity to each other. His observations led him to conclude that certain land areas had been connected in the past while others never were.

This revelation "defined a dividing line between the fauna of Asia and Australia," that "would be known as the 'Wallace Line'" (57).

Henry Walter Bates' contributions round out the first section. Another explorer and observer of the little known reaches of the Amazon basin, Bates is best known for his observations of animal mimicry. Bates noted many examples of harmless species that look remarkably like a distasteful or poisonous species. These observations came into focus for Bates in light of the publication of The Origin of Species. Darwin was very pleased with Bates' discoveries as they provided one of the earliest bodies of evidence supporting Natural Selection (68).

Evidence for evolution continues to accumulate with the explorers and scientists in the next section of Remarkable Creatures, The Loveliest Bones. Carroll engages the reader with the adventures of Eugène Dubois, the discover of Java Man and Roy Chapman Andrews who discovered the first dinosaur eggs in the Gobi Desert. Added to the mix is Charles Doolittle Walcott whose name is very familiar to collectors of invertebrate fossils. Carroll also chronicles the Alvarez story and the extinction by asteroid theory for the demise of the dinosaurs.

The story of John Ostrom and the ultimate discovery of feathered dinosaurs fills another chapter in the Loveliest Bones section. You may recall that John Ostrom is the discoverer of Deinonychus, a small theropod dinosaur with sickle-like killing claws on its feet. As Carroll explains, Ostrom's analysis of Deinonychus changed the accepted view of dinosaurs - "they weren't lumbering oafs, they weren't stupid, they weren't cold- blooded, and, most startling of all, they weren't extinct" (163). Ostrom's study of Deinonychus led him to the conclusion that this little dinosaur had many birdlike features. To supplement this conclusion, he traveled to Europe to study the "first" bird fossil, Archaeopteryx. Carroll fills in the back story about Archaeopteryx and its initial interpretation as an unequivocal bird - not a dinosaur - by Richard Owen. This part of the story reveals Owen as an antievolutionist at odds with the likes of Darwin and Huxley who saw this fossil as a transitional creature in support of evolution. Ostrom actually "found" the fifth fossil Archaeopteryx known at that time, mis-identified as a Pterosaur in the Teyler Museum in the Netherlands. In 1973, the culmination of Ostrom's research brought him to a striking conclusion, as Carroll states, "birds evolved from a dinosaurian ancestor" and "that they were, in fact, dinosaurs" (174).

The concluding chapter in this section covers the recent work by Neil Shubin and his discovery of another important transitional fossil - the "fishapod." Unlike some of the greatest discoveries of important fossils, Shubin was actually trying to find the most unequivocal transitional fossil between fish and amphibians. A good sequence of transitional fossils along this line were already known but the one to fill the final hole in the sequence had not been found. Shubin knew he had to look in sedimentary rocks in the 380 to 360 million year old range. A literature search produced potential sites in Canada. Carroll recounts the challenges of Shubin's expeditions. There were government and sometimes Eskimo permissions to be obtained. Travel to the sites by helicopter or bush plane was necessary and dangerous. At camp, they even installed a trip wire early warning system for roving polar bears. The fourth expedition finally produced the creature now known as Tiktaalik, the missing transitional form between fish and amphibians that Shubin had sought.

Carroll's final section, The Natural History of Humans, includes three chapters with at least one person you may previously not have linked with evolution or paleontology - Linus Pauling. Carroll recognizes the contributions of the most famous family in paleoanthropology in another chapter - the Leakey family, who have studied and continue to study the fossils and artifacts of early hominids in east Africa. Rounding out this section is a summary of the very current work on Neanderthals.

Carroll chronicles Pauling's life as a winner of two Nobel Prizes, an anti-nuclear proliferation activist and a suspected communist in the early 1950's. Pauling was at his most active as an anti-nuclear weapon activist when H-bomb testing was escalating. He linked radiation with genetic mutation and further linked that to some human diseases (241). Pauling, a chemist, began to study biology and evolution to bolster his background in genetics to support his activist role. He teamed with a French scientist Emile Zuckerkandl. The two men's work ultimately led to the development of the "molecular clock" based on genetic mutations in DNA. Originally opposed by noted evolutionists Ernst Mayr and George Gaylord Simpson (244), their work has been vindicated and supported by fossil evidence. The principles Pauling and Zuckerkandl developed are now used to estimate how long ago various lineages of animals diverged from one another - including humans and apes. The final chapter in Part Three details the early and most recent work on the Neanderthals' place in the human family tree. It has been well known for some time that Neanderthals and early modern humans overlapped in time and perhaps in space as well. There are those who say that certain eastern European groups have some anatomical traits of the Neanderthals leading to speculation that the two groups not only met but interbred. All is mere conjecture without more substantial evidence. Carroll's story leads up to and describes the very recent work by Svante Pääbo in sequencing Neanderthal nuclear DNA.

At the time of publication of Remarkable Creatures the first results found no Neanderthal genetic contribution to modern human DNA - but that work continues. Prior to the Neanderthal DNA work, Allan Wilson, Rebecca Cann and Mark Stoneking looked at the DNA of a range of modern peoples. The result of their work with mitochondrial DNA resulted in the "Out of Africa" or "Mitochondrial Eve" theory that places modern human origins in Africa with subsequent migration outward. Carroll discusses all of the developmental aspects of this work and the vehement opposition by paleoanthropologists who held that hard fossil evidence was the only way to discern evolutionary relationships and the timing of divergence.

Each of the chapters contain many fascinating stories of the people and research in evolution over the past 200 years. Carroll has made this a fascinating and interesting book that discusses the detail of evolutionary studies and also the impact that those studies had on our long term understanding of the natural world. Had another author written Remarkable Creatures, I am certain that Carroll's own work on evolutionary development would have merited its own chapter. Readability - An easy and interesting book suitable for general readers. The lack of highly technical topics makes Remarkable Creatures good for even younger readers.

On the Upside - Fascinating stories of true adventure and discovery. Each chapter is engaging. Carroll explains how each of the individuals' work has related to the discovery and development of evolutionary theory.

On the Downside - Carroll could easily have included a chapter on his own work and discoveries within Remarkable Creatures as a fitting final chapter. Perhaps modesty did not allow for this.

Overall Rating - A reader friendly look at evolutionary studies that should not be missed.


Click here to read the previous issue. Click here to read the next issue.