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72 life elsewhere, the passive trends toward increases in organismal size, complexity, and diversity are certain to prevail.’ In the case of Earth life, what we regard as complex is usually inherent in simpler systems. Although this process takes time, what was impossible billions of years ago may become increasingly likely. Take multicellularity. Darling saw this as a convergent property that bestows such overwhelming advantages that we will see it implemented routinely wherever living things emerge. The same is true of mobility.”° Evolutionist Ernst Mayr, although skeptical about extraterrestrial life and intelligence, acknowledged convergent evolution on Earth. Eyes evolved independently at least 40 times in different groups of animals.” Recent research has offered additional support for convergence. “A lot of studies are finding quite a lot of surprising replicability of evolutionary outcomes,” said evolutionary biologist Richard Lenski. “There’s more to repeatability than we had suspected a decade ago,” concluded Loren Rieseberg, another evolutionary biologist. He and his colleagues found evidence that evolution can repeatedly produce the same species.” The evolutionary route that led to life seems to have taken the way with the fewest obstacles and to have chosen the most abundant construction materials available, argued planetary scientist Armand Del- semme. The genetic code appears to be well adapted to maximize the probability that mutation will lead to an improvement in the resulting protein.” On the spectrum between total chance and complete determinism, concluded Davies, only an exceedingly tiny window would correspond to sparse life. If the truth lies to the deterministic side of that window, life will be common; if it lies much to the chance side, it will have happened only once in the observable universe. The discovery of one life-form with a different physical or chemical basis would settle the issue.** Catastrophic Punctuation Some scientists see a powerful connection between asteroid and comet impacts and the evolution of life on Earth. Citing the theory of “punctu- ated equilibrium” developed by evolutionists Stephen Jay Gould and Niles Eldredge, they argue that massive extraterrestrial impactors may have been the cause of this punctuation, provoking vulcanism, tectonic movements, and mountain building as well as atmospheric change. The great extinction of 250 million years ago, which may have been caused by an impactor, by massive vulcanism, or both, was catastrophic; some researchers believe that life was nearly exterminated. Yet, life not only survived, it flourished.”° Probabilities: Life