Gamma Rays Burst Biological Evolution
The energy released during a gamma ray burst strains the imagination. With the power of 10 billion billion suns, gamma ray bursts are the most brilliant photon emitters in the universe. By comparison, supernovae emit (at peak) the energy equivalent of 100 billion suns. If such a gamma ray burst occurred closer than millions of light years away and lasted longer than a few minutes—or in some cases, milliseconds—humanity would be wiped out.
Until recently, astronomers presumed that all threats to life on Earth lay within a few hundred light years of the solar system. A new generation of telescopes has proved otherwise. Most, if not all, gamma ray bursts arise from the rapid collapse of ultra massive stars into black holes.1 A few may result from the merging of black holes and/or neutron stars. Researchers discovered that gamma rays from thousands—even tens of thousands—of light years away can disturb life on Earth.
Death Rays or Evolution Boosters?
University of Texas astronomers John Scalo and Craig Wheeler report that supermassive stars frequently form in close proximity to one another both in nearby galaxies and in the Milky Way.1 Such star formation episodes lead to the kind of rapid collapses and mergers that produce gamma ray bursts. Scalo and Wheeler calculate that at least one thousand of these radiation events (powerful enough to disturb or destroy life) have taken place during the 4-billion-year history of life on Earth. In other words, such an event occurs, on average, at least once every 4 million years. Humanity exists on Earth in a window between these deadly bursts.
The Texas astronomers’ main interest lies in the effect of gamma ray bursts on animal life throughout geologic history and in the related implications for possible past life on Mars. They define a “biologically significant” gamma ray burst as a radiation dose strong enough to double the mutation rate in animal species. A lethal dose is three to ten times stronger, depending on the animal species. A conservative estimate suggests that Earth has experienced 50 or more lethal blasts during the past 4 billion years.
Evolutionists see episodes of mutation rate increase as a good thing. They assume that higher mutation rates spurred the development of new survivable species from old, dying ones. The weakness of their assumption is in the numbers, however; at least ten thousand deleterious or harmful mutations occur for every (conceivably) beneficial one, whatever the radiation environment. In some cases, the ratio reaches as high as 10 million to one. Except in tiny body-size, high-population, short-generation species,2 increasing the mutation rate simply hastens the extinction of a species.3
Because Mars’ atmosphere is thin, biologically significant (as well as lethal) gamma ray bursts affect Mars more frequently than they do Earth. According to one study, a lethal gamma ray dose strikes Mars on the average of once every 2.5 million years. Such frequent radiation doses give scientists one more reason out of many to conclude that, apart from the stray Earth life that occasionally gets carried to Mars as a result of meteorite impacts, Mars remains a sterile planet.
Resolving Fossil Record Mysteries
This study of gamma ray bursts may help solve some mysteries in the fossil record. For example, extinctions sometimes appear in one hemisphere and not the other. Since a gamma ray burst lasts an hour or less (ten seconds, on average), a single burst could impact only one hemisphere. The more powerful or nearby repeated gamma ray bursts may account for some of the global extinctions paleontologists observe in the fossil record.
Studies of distant galaxies show that gamma ray bursts were much more prevalent 3-5 billion years ago. (At that time, the star formation rate in galaxies, including the Milky Way, was much higher.) The higher rate of gamma ray bursts may explain why Archaean organisms (single-celled bacteria-like organisms with many gene products, distinct from all other life forms) dominated life’s earliest epoch on Earth. Such organisms are the most radiation resistant life forms. Archaean organisms can withstand radiation levels a hundred times higher (some, up to ten thousand higher) than can other animal species.
While these deadly gamma ray bursts represent a potent challenge to evolutionary theory, they do seem consistent with the Reasons To Believe speciation model.4 RTB’s model describes God’s efficient removal of old species to make room for newly created ones. This extinction-replacement process would be part of God’s step-by-step preparation of Earth for humanity.5 That is, gamma ray bursts played a significant role in making Earth fit for human life. A biblical creation model also gives assurance that God will fulfill His plans for life on Earth relatively soon, at least in the few million years or less before the next deadly gamma ray burst.
- Jan van Paradijs, “From Gamma-Ray Bursts to Supernovae,” Science 286 (1999): 693-95.
- John Scalo and J. Craig Wheeler, “Astrophysical and Astrobiological Implications of Gamma-Ray Burst Properties,” Astrophysical Journal 566 (2002): 723-37.
- Unless the species has an enormous population base (typically, in excess of a quadrillion individuals), a tiny average body size (typically, smaller than one centimeter across), and a short time period between the birth of an individual and its capacity to reproduce (typically, briefer than three months), so as to give natural selection enough material from which to efficiently select (in the time available), increasing the mutation rate hastens the extinction of the species.
- Mark Ridley, Evolution, 2d ed. (Cambridge, MA: Blackwell Science, 1996), 247-52; Hugh Ross, The Genesis Question, 2d ed. (Colorado Springs, CO: NavPress, 2001), 52-54.
- Scalo and Wheeler close their paper by announcing that they will soon publish similar studies on the life-disturbing impact of other galactic events. They mention these five: (1) ultraviolet bursts associated with supernova shock breakouts, (2) ultraviolet, x-ray, and gamma ray radiation from peak eruption phases of supernova eruptions, (3) soft gamma ray repeaters, (4) flare stars, and (5) massive O-type stars. Apparently, these coming studies may provide more detailed confirmations for biblical teachings about extinctions, speciation, and the history of life on Earth.
- See Psalm 104:24-30 and Hugh Ross, “The Faint Sun Paradox” Facts for Faith 10 (Q3 2002), 27-33.