The Institute for Creation Research

Cichlid fish are a top biological model for the study of diversification because of their unique ability to adapt to a wide range of lake and river environments. They also produce a startling array of unique traits. For creation scientists, they are particularly interesting because they provide an opportunity to illustrate how creatures are able to track their environments and respond accordingly to produce traits that allow them to succeed as a result of their internally engineered systems.¹ A new study confirms creationist predictions for a type of internal adaptive engineering in the genome.²

Many traits in plants and animals are difficult to study because their underlying genetic basis is very complex and controlled by the interaction of large networks of genes and pathways. So, trying to figure out which gene is doing what can be nearly impossible. However, a few traits in cichlids lend themselves to genetic study because they are associated with a fewer number of genes with larger effects.^3-5 These more easily studied traits are related to coloration (pigmentation), some aspects of jaw development, and several adaptations of the visual system.

In this new study, the researchers made crosses between cichlids with markedly different traits and then analyzed the progeny for genetic differences.² More specifically, the team analyzed gene expression (products of active genes) associated with specific locations on the fish’s chromosomes associated with the adaptive traits of the cichlid visual system. The researchers found that four locations in either the controlling regions or within the main gene itself were altered by large insertions or deletions of DNA. These altered regions were associated with cone opsin genes that are involved in tuning the spectral sensitivity of the fish through differential gene expression.⁶ This is a key adaptation because different lake and river environments have varying clarity and spectral conditions—a key factor in finding food or avoiding being eaten.

But the most amazing discovery in the project was that the insertions and deletions were found to be “primed” for modification by a specialized genetic feature called a transposable element. This feature was found to be activated by hybridization (mating) and was believed to provide the ability to create rapid adaptive optic traits allowing the fish population to adjust to the conditions at hand. In other words, the modifications were not random, but brought about by an engineered system of genetic targeting and modification to facilitate adaptation. Not only that, the areas primed for alteration were exactly where they needed to be—in specific locations within the optic genes to fine-tune the visual system. Any sort of random mutation to these genes would be disastrous to the fish’s vision.

Unfortunately, much of this type of research is hampered by evolutionary presuppositions that perpetually attempt to attribute elaborate and complex systems of adaptation to mystical random naturalistic processes. Just think how much more progress would be made if researchers were looking for design and purpose in living creatures. Despite the failed naturalistic preconceptions of many secular scientists, the amazing truth of complex internal creature engineering by our mighty Creator continues to shine forth in studies like this.

References
1. Guliuzza, R. J., and P. B. Gaskill. 2018. Continuous environmental tracking: An engineering framework to understand adaptation and diversification. In Proceedings of the Eighth International Conference on Creationism, ed. J. H. Whitmore. Pittsburgh, PA: Creation Science Fellowship, 158-184.
2. Carleton , K.L. et al. 2020. Movement of transposable elements contributes to cichlid diversity. bioRxiv preprint doi: https://doi.org/10.1101/2020.02.26.96198
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3. Conith, M. R. et al. 2018. Genetic and developmental origins of a unique foraging adaptation in a Lake Malawi cichlid genus. Proceedings of National Academy of Sciences USA. 115(27): 7063-7068.
4. Kratochwil, C. F. et al. 2018. Agouti-related peptide 2 facilitates convergent evolution of stripe patterns across cichlid fish radiations. Science. 362 (6413): 457-460.
5. Malinsky, M. et al. 2018. Whole-genome sequences of Malawi cichlids reveal multiple radiations interconnected by gene flow. Nature Ecology Evolution. 2(12): 1940-1955.
6. Parry, J. W. et al. 2005. Mix and match color vision: tuning spectral sensitivity by differential opsin gene expression in Lake Malawi cichlids. Current Biology. 15(19): 1734-9.

*Dr. Tomkins is Life Sciences Director at the Institute for Creation Research and earned his doctorate in genetics from Clemson University.