Divining Darwin in Butterfly Genes
When you look into the crystal ball of DNA, do you see evolution? A team of scientists carefully examined genomes of a butterfly and a silkworm. What they found was interesting, but dubious as an example of evolutionary ancestry.
Publishing in PLoS ONE, scientists from the U.S., Netherlands, and Portugal took partial data from the African Bush Brown Butterfly (Bicyclus anynana), known for the dazzling array of eyespots on its wings. (The photo above depicts androconial scales; credit: Gilles San Martin.) The researchers compared this data with the published genome of the silkworm moth. Butterflies and moths (both members of the insect order Lepidoptera) are thought to have diverged 140 million years ago. What the scientists found on this expedition in search of divination was, like most oracles, ambiguous. Some results seemed to support common ancestry while others did not.
The team found, for instance, that gene order (synteny) was remarkably conserved. "The general properties and organization of the available B. anynana genomic sequence are similar to the lepidopteran reference [i.e., silkworm genome], despite the more than 140 MY [million year] divergence." It should be noted that conservation is the opposite of evolution. On the other hand, they found putative chromosomal rearrangements, inversions, and transpositions. Perhaps most surprisingly, they "detected instances of unusual high conservation of non-coding regions, in particular, around the genes encoding for Ecdysone Receptor and Wingless, between species diverged some 140 MYA." This is a further indication, of course, that non-coding regions of the genome, previously dubbed "junk DNA," are functional.
Even so, it is not clear which findings reflect reality and which might be artifacts of the software and methods the team chose. "Comparative studies of sequence, expression and function of these genes are necessary to shed light onto their evolutionary history and ecological importance," the authors admitted in conclusion, failing to specify any clear victories for evolutionary theory. Speaking of the conserved non-coding regions, they commented, "Understanding the functional significance of these regions will allow for a better understanding of the evolution and diversification of living organisms." In other words, they ain't there yet.
It's doubtful this heroic effort has shed any light on evolution. Nor is likely that similar efforts will do so any time soon. "The Lepidoptera have an unusual set of genetic properties, combining holocentric chromosomes, heterogametic females, and male-restricted meiotic recombination, whose consequences for genome evolution remain largely unexplored," the researchers conceded up front, even though they know "Butterflies have interesting biological properties (such as color vision and novel wing color patterns) and include many textbook examples of studies in ecology and evolution -- for example, long distance migrations of monarchs, mimicry in Papilio and Heliconius, mutualistic relationships between lycaenids and ants, and wing pattern plasticity and evo-devo in Bicyclus and Junonia." How those textbook examples support evolution was passed to the references section, where any mention of the best textbook example -- the peppered moth -- was noteworthy for its absence.
Researchers like these are obsessed with divining evolution in the genes, but science would be better served by understanding the observable aspects of butterflies. The most remarkable and fascinating aspect is one that defies Darwinism: the transformation from crawling caterpillar to adult butterfly. The "magic" of metamorphosis, its challenge to evolutionary theory, and the positive evidence it provides for intelligent design, are all explored fully in the beautiful new documentary Metamorphosis from Illustra Media. With original research and MRI imaging, this powerful film advances the scientific study of butterflies. It also refutes the insinuation that "long distance migrations of monarchs" provides a textbook example of evolution.
To learn more about butterflies and the evidence they reveal for intelligent design, visit Metamorphosisthefilm.com, where you can watch the trailer and order this outstanding film, now available in both DVD and Blu-Ray formats.