What the Paper Claims
This comprehensive study of six bat species’ genomes claims to reveal “the evolution of bat adaptations” and provide insights into how bats supposedly evolved their remarkable abilities like echolocation, flight, and extraordinary immune systems. The researchers sequenced high-quality genomes from six different bat species and analyzed them for signs of evolutionary changes, particularly focusing on genes related to hearing, immunity, and other specialized bat traits.
Key Findings and Critical Analysis
Finding 1: “Positive Selection” on Hearing Genes
The paper states: “Our genome-wide screens revealed positive selection on hearing-related genes in the ancestral branch of bats, which is indicative of laryngeal echolocation being an ancestral trait in this clade.”
What the researchers actually found were variations in genes already present in mammals, with certain versions being more common in echolocating bats. This isn’t evidence of new genetic information being created—it’s evidence of existing genetic variants being selected for their effectiveness in different environments. The sophisticated echolocation system was already present in the ancestral bat population, suggesting it was part of the original design rather than a later evolutionary innovation.
Finding 2: Gene Loss, Not Gene Gain
The researchers report: “This revealed 10 genes that are inactivated in our 6 bat species but that are present in the majority of non-bat members of Laurasiatheria.”
Here we see a clear example of information loss, not gain. Bats have lost the function of 10 genes that other mammals retain. Two of these lost genes were involved in immune system inflammation. While this loss may provide some adaptive advantage by reducing harmful inflammation, it represents a reduction in genetic information—the opposite of what’s needed for molecules-to-man evolution. The paper also notes: “We identified 286 conserved miRNA gene families across all mammals, 11 of which were significantly contracted (false discovery rate < 0.05), and 13 of which were lost, in the ancestral bat branch.”
Again, this shows widespread loss of regulatory elements, not the creation of new functional information.
Finding 3: Sophisticated Immune System Adaptations
The paper describes: “We found selection and loss of immunity-related genes (including pro-inflammatory NF-κB regulators) and expansions of anti-viral APOBEC3 genes, which highlights molecular mechanisms that may contribute to the exceptional immunity of bats.”
What’s remarkable here is the sophisticated, coordinated changes in bat immune systems. The researchers found that bats have fine-tuned their immune responses through multiple coordinated genetic changes—some genes are turned down, others are amplified, and some are lost entirely. This level of coordinated optimization across multiple biological systems suggests purposeful design rather than random mutations being filtered by natural selection.
Why This Isn’t Evidence for Macroevolution
The findings in this paper demonstrate exactly what creationists would expect: sophisticated creatures showing remarkable design features and the ability to adapt within their created kind through existing genetic variation. The “evolution” described here is entirely within the bat family—no new body plans, organs, or fundamentally new biological systems are being created.
The researchers are observing microevolution and adaptation, not macroevolution. Bats remain bats throughout their supposed evolutionary history. The phylogenetic trees they construct assume common descent but could equally support common design, where similar genetic toolkits were used to create different but related creature types.
Most tellingly, the innovations that make bats unique—powered flight, sophisticated echolocation, and extraordinary immune systems—are all treated as already present in the “ancestral bat.” The paper doesn’t explain how these remarkable systems arose in the first place, which is exactly the kind of innovation that molecules-to-man evolution requires.
Scientific Context
Molecular biologist Dr. Michael Behe has extensively documented that while organisms show remarkable ability to adapt through existing genetic variation, true evolutionary innovation requiring new functional information is extremely rare or absent in the scientific literature. The bat genome study fits this pattern perfectly—showing sophisticated adaptation within strict limits, but no evidence of the kind of information-building processes that would be needed to transform a small mammal into a flying, echolocating bat in the first place.
The Discovery Institute’s work on biological information theory also emphasizes that functional biological information requires intelligent input, not random processes. The coordinated genetic changes described in bats suggest purposeful optimization rather than undirected evolutionary processes.
Bottom Line
This impressive genomic study reveals bats as sophisticated, well-designed creatures with remarkable adaptive capabilities, but provides no evidence for the kind of information-building evolutionary processes needed to support the microbes-to-man narrative.
Abstract
Six reference-quality genomes reveal evolution of bat adaptations
David Jebb, Zixia Huang, Martin Pippel, Graham M. Hughes, Ksenia Lavrichenko, Paolo Devanna, Sylke Winkler, Lars S. Jermiin, Emilia C. Skirmuntt, Aris Katzourakis, Lucy Burkitt-Gray, David A. Ray, Kevin A. M. Sullivan, Juliana G. Roscito, Bogdan M. Kirilenko, Liliana M. Dávalos, Angelique P. Corthals, Megan L. Power, Gareth Jones, Roger D. Ransome, Dina K. N. Dechmann, Andrea G. Locatelli, Sébastien J. Puechmaille, Olivier Fedrigo, Erich D. Jarvis, Michael Hiller, Sonja C. Vernes, Eugene W. Myers & Emma C. Teeling
Bats possess extraordinary adaptations, including flight, echolocation, extreme longevity and unique immunity. High-quality genomes are crucial for understanding the molecular basis and evolution of these traits. Here we incorporated long-read sequencing and state-of-the-art scaffolding protocols to generate, to our knowledge, the first reference-quality genomes of six bat species (Rhinolophus ferrumequinum, Rousettus aegyptiacus, Phyllostomus discolor, Myotis myotis, Pipistrellus kuhlii and Molossus molossus). We integrated gene projections from our ‘Tool to infer Orthologs from Genome Alignments’ (TOGA) software with de novo and homology gene predictions as well as short- and long-read transcriptomics to generate highly complete gene annotations. To resolve the phylogenetic position of bats within Laurasiatheria, we applied several phylogenetic methods to comprehensive sets of orthologous protein-coding and noncoding regions of the genome, and identified a basal origin for bats within Scrotifera. Our genome-wide screens revealed positive selection on hearing-related genes in the ancestral branch of bats, which is indicative of laryngeal echolocation being an ancestral trait in this clade. We found selection and loss of immunity-related genes (including pro-inflammatory NF-κB regulators) and expansions of anti-viral APOBEC3 genes, which highlights molecular mechanisms that may contribute to the exceptional immunity of bats. Genomic integrations of diverse viruses provide a genomic record of historical tolerance to viral infection in bats. Finally, we found and experimentally validated bat-specific variation in microRNAs, which may regulate bat-specific gene-expression programs. Our reference-quality bat genomes provide the resources required to uncover and validate the genomic basis of adaptations of bats, and stimulate new avenues of research that are directly relevant to human health and disease.
Published in Nature, available at: https://www.nature.com/articles/s41586-020-2486-3