Koonin, a Senior Investigator at NIH and Editor-in-Chief of Biology Direct, sees all the current research and integrates it with existing knowledge to the extent possible. This integration, however, requires major amendments to the prevailing paradigm, and he is blunt about that. "...Our understandng of evolution—and with it the very nature of biology—have forever departed from the prevailing views of the twentieth century that today look rather naïve and somewhat dogmatic" (p x).

Koonin is impressed by "a remarkable contrast between the relative evolutionary stability of individual genes, many of which retain their indentity over hundreds of millions or even billions of years of evolution, and the maleability of composition and architecture of genomes that change orders of magnitude faster" (p 77). Here and elsewhere, he reinforces to us the view that genes could be older than life on Earth. Of course, he does not go that far. Rather, in support of the basic darwinian belief that life can originate, probably on this planet, he is quite inventive. Yet nowhere in the book do we see any credible accounting for new genes. Instead, he mentions only briefly, "...the emergence of a new gene, typically via gene duplication, followed by radical divergence...," with no further elaboration (p 331). Radical divergence erases the details, apparently. Besides, what about the "relative stability" just mentioned?

Horizontal Gene Transfer (HGT) is very well known to him. "...Even a gene that is found in all modern cellular life forms might not be inherited from LUCA: Its ubiquity could instead result from an HGT sweep" (p 331). He also classifies viruses as a huge separate "empire" of life that interacts furiously with all cellular life. "...These findings suggest that the Virus World largely 'builds' the genomes of cellular life forms and so shapes the evolution of life in general" (his italics, p 301). Wow, he knows that?

We learned more than ever about the details and varieties of, and difficulties for, the RNA World and other origin-of-life theories. Koonin admits, "The difficulty of the problem cannot be overestimated" (p 329). Yet he is hopeful. How hopeful? "We are even starting to develop scenarios for the origin of cells that may go beyond sheer speculation" (p 401)! His own speculations include a "Many Worlds" construct in which our biological world is vanishingly unlikely — the weak anthropic principle, he says (p 384). Please remind us, why is panspermia considered so outrageous? Nevermind. We were tremendously edified by The Logic of Chance. But also discouraged. Apparently, no amount of difficulty weakens darwinism's faith enough to allow consideration of alternatives like cosmic ancestry.

The topics range widely and his knowledge is deep and up-to-date. Of course, we were disappointed that he showed little interest in panspermia, and instead concentrate[s] on a terrestrial origin of life (p 31). And although his thoughts on evolution are confined to strict darwinism, he is at least aware of the evidence for gene transfer and for genes older than their corresponding phenotypes (p 77-79).

"Gaia" is not listed in the 7-page index, but Catling knows plenty about the evolution of planetary atmospheres, plate tectonics, and other environmental processes that interact and coevolve with life. In fact, he is co-authoring a forthcoming book, Atmospheric Evolution on Inhabited and Lifeless Worlds. We will be especially interested to know his considered thoughts about Titan, with its abundant methane, on which he comments briefly, already, here. Of course life makes methane, and methane has profound Gaian effects.

Today's book begins by asking "What is astrobiology?" Catling answers with some history and some alternative definitions, including his favorite, a branch of science concerned with the study of the origin and evolution of life on Earth and the possible variety of life elsewhere. To anyone interested in these issues, we recommend the book.

The analysis considers 71 kinds of TFs and plots their distribution among eukaryotes. The results are entirely about the gain or loss of TFs, or their enrichment in number. By using comparative genomics, we show that plants and animals required richer transcriptional machineries compared with other eukaryotic multicellular lineages. Many TFs are found in simpler species with no apparent use for them, so they appear to be much older than necessary. And for all TFs, too old or not, the term "origin" actually refers to their first appearance, not to any incremental darwinian evolution.

In cosmic ancestry, evolutionary advances follow the installation and deployment of existing genetic programs. In strict darwinian evolution however, genetic programs cannot already exist before deployment. Rather, the deployment and the "origin" of any genetic program must happen concurrently, while natural selection uses trial-and-error to compose the program. We carefully follow the scientific literature to see which scenario is actually observed. Today again, we discern the former scenario, and evidence for darwinian program-composition is conspicuously missing.

Meanwhile, members of the same team observed T-box genes that apparently existed before their deployment. The T-box transcription factors are key players in animal development and they were considered strictly animal-specific. We show that T-box genes have instead an important premetazoan evolutionary history, being present in several nonmetazoan unicellular taxa. More jarring news for strict darwinism. We welcome informed comments.

Bioinformaticians from Columbia University and Stanford have employed algebraic topology to model the evolution of certain viruses. The resulting, multi-dimensional figures are not at all like darwinian trees. We note that horizontal evolution is a basic prediction of cosmic ancestry.

We are pleased that Eigen sees inventive evolution and the origin-of-life as closely related problems, both beset by the software issue. For that he prefers the term "information," and often qualifies it with "meaning," so he deals head-on with the topic of our interest. A substantial portion of the book is about entropy and the second law of thermodynamics, including how evolution and the origin-of-life may get around [the logical analog of] this law — again, perfect for us. He acknowledges the difficulties: "At this stage it suffices to conclude that a closed and formal system cannot generate any information that is not inherent in its algorithms..." (p 285). And immediately he notices that the biosphere is not closed. But he means that it is open to energy and matter, not genetic programs as cosmic ancestry requires. His ultimate affirmative solution is too subtle for us to grasp.

At the 5th Annual Conference on Bioastronomy in Capri, Italy, in 1996, I met Manfred Eigen. Following his paper there on the same themes, I asked a question: Can he name any convincing example in which substantial new encoded programming has been self-generated within a closed system? He reacted with hostility: "What does that have to do with what we are discussing here?" I was completely surprised and abashed by his reaction. I did not then know that only a creationist would dare to ask such a question, and creationists are always treated with contempt. I meekly rephrased and he replied, but his reply provided no satisfaction — nor any convincing example. None in the new book either. I wonder if he would be interested in the challenge of the "Evolution Prize" that we promoted in 2006.

Twenty years ago, Eigen believed the origin-of-life required "proteins first." Now he has switched allegiance to the RNA World. Apparently, he thinks the hardware problem is better solved that way. For cosmology, Eigen accepts the big bang, but he acknowledges variants of the theory that would allow life from the eternal past. We wish he would let himself entertain that possibility.

The book is full of anecdotes and references to other 20th century scientists, most of whom he knows personally. Our disagreements aside, it's a very readable, informed, probing, exhaustive discussion of issues related to the origin of life. And he plans a sequel of five more chapters. Wow.