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We often hear from Darwinians that the biological world is replete with examples of shoddy engineering, or, as they prefer to put it, bad design. One such case of really poor construction is the inverted retina of the vertebrate eye. As we all know, the retina of our eyes is configured all wrong because the cells that gather photons, the rod photoreceptors, are behind two other tissue layers. Light first strikes the ganglion cells and then passes by or through the bipolar cells before reaching the rod photoreceptors. Surely, a child could have arranged the system better — so they tell us.

The problem with this story of supposed unintelligent design is that it is long on anthropomorphisms and short on evidence. Consider nocturnal mammals. Night vision for, say, a mouse is no small feat. Light intensities during night can be a million times less than those of the day, so the rod cells must be optimized — yes, optimized — to capture even the few stray photons that strike them. Given the backwards organization of the mouse’s retina, how is this scavenging of light accomplished? Part of the solution is that the ganglion and bipolar cell layers are thinner in mammals that are nocturnal. But other optimizations must also occur. Enter the cell nucleus and “junk” DNA.

Only around 1.5 percent of mammalian DNA encodes proteins. Since it has become lore to equate protein-coding regions of the genome with “genes” and “information,” the remaining approximately 98.5 percent of DNA has been dismissed as junk. Yet, for what is purported to be mere genetic gibberish, it is strikingly ordered along the length of the chromosome. Like the barcodes on consumer items that we are all familiar with, each chromosome has a particular banding pattern. This pattern reflects how different types of DNA sequences are linearly distributed. The “core” of a mammalian chromosome, the centromere, and the genomic segments that frame it largely consist of long tracks of species-specific repetitive elements — these areas give rise to “C-bands” after a chemical stain has been applied. Then, alternating along the chromosome arms are two other kinds of bands that appear after different staining procedures. One called “R-bands” is rich in protein-coding genes and a particular class of retrotransposon called SINEs (for Short Interspersed Nuclear Elements). SINE sequence families are restricted to certain taxonomic groups. The other is termed “G-bands” and it has a high concentration of another class of retrotransposon called LINEs (for Long Interspersed Nuclear Elements), that can also be used to distinguish between species. Finally, the ends of the chromosome, telomeres, are comprised of a completely different set of repetitive DNA sequences.

This week Inside Catholic republished an absolutely brilliant essay by Discovery Institute Senior Fellow Benjamin Wiker on the problem of evil. This essay is one of the most thoughtful replies to the problem of evil — that the existence of evil evidences against God’s existence — I’ve seen packed into a short essay. It is a must read. Wiker describes how, in a feat of fuzzy thinking, evolution typically plays into dialogue on the problem of evil. Evolutionary answers to the problem, he argues, are more likely to do away with evil than explain it. And among the many important questions Wiker poses is whether we really want all evil purged from the earth. Take a look to see his Read More ›