Nebraskan deer mice—evolution’s latest ‘icon’?
Mutations and natural selection are at work in deer mouse populations in Nebraska’s sand hills, but there’s no evidence of evolution
One of the most abundant and widespread mammals in north America is the deer mouse (Peromyscus maniculatus). Usually the mice have a dark coat—very useful for enabling them to blend in with dark soils and avoid being seen by predators such as owls and hawks.
In Nebraska’s rolling sandhills1 however, which are composed mostly of light-coloured quartz grains, deer mice are predominantly a pale, orange-blonde or tan colour.
And so researchers pondered the question: Is the lighter-coloured sandy coat an adaptation that helps deer mice to survive in the sandhills habitat?
Using light-coloured and dark-coloured plasticine models of mice at several sites in the Nebraskan sandhills, the researchers observed, as expected, that the conspicuous dark models were attacked by predatory birds much more often than the sandy-coloured model mice.2 This was in line with earlier experiments using live deer mice and predatory owls.3 Thus, the researchers could justifiably assert that pale-coloured deer mice do indeed have “a strong selective advantage” over dark-coloured deer mice in such habitats, being better camouflaged from visually hunting predators.2
Producing pigments—light vs dark
The pigment-producing cells in mice make a brown pigment called eumelanin and a light-coloured pigment called pheomelanin (also responsible for ‘red’ hair4). If the production of eumelanin is suppressed, more pheomelanin is produced, resulting in a light-coloured mouse. A single gene known as the Agouti gene produces a protein that regulates eumelanin production and thus also the amount of pheomelanin produced. The pale-coloured mice have a mutated Agouti gene—an amino acid has been deleted from the product of the gene—resulting in an over-active suppression of eumelanin production.2,5 As a result, much more pheomelanin is produced. Thus the Agouti mutation generates wider pale bands of dorsal (back) hairs, making the entire animal appear a golden sandy colour rather than dark brown.6
Further genetic analysis of the Nebraskan pale deer mice populations identified multiple mutations of that same gene, which have resulted in “multiple pigmentation traits that together give rise to the overall cryptic [i.e. better-camouflaged] appearance of the Sand Hills mice.”2
The researchers have concluded, quite legitimately, that “this study vividly illustrates the power of natural selection.”7 They also conclude, reasonably enough, that the mutation(s) for pale fur arose sometime after deer mice began to colonize the Nebraskan sandhills.
Natural selection, for sure
“The light gene wasn’t in existence, so the mice had to ‘wait’ until a particular mutation occurred and then selection had to act on that new mutation,” said team member Hopi Hoekstra, of Harvard University. “It’s a two part process. First the mutation has to occur and second, selection has to increase its frequency.”8 As pale mutants were more likely than dark mice to survive and breed, passing the mutated gene to the next generation, the adaptation for pale fur quickly became widespread in the sandhills population.
Thus far, all good—if they’d simply left their statements at that, fine. As informed creationists have pointed out many times, we have no problem with the terms natural selection, mutations, and adaptations when properly applied.9 Indeed, we never had problems in principle with the similar story of natural selection of dark or light peppered moths (Biston betularia) in England, even before the discovery of staged photos.10 However, the researchers and science publications have portrayed the findings as evidence of evolution,2,7,11 duly glibly relayed by secular mass media outlets.8,12 And, possibly being aware that creationists repeatedly and successfully challenge evolutionary claims (of microbes-to-man evolution) by correctly pointing out that in many instances there has only been selection from pre-existing genetic variation, the researchers were particularly eager to highlight the “de novo”5 appearance of the mutated gene: “Our work shows that rapid adaptive change, such as the evolution of lighter coloration among Sand Hills mice, need not always rely on pre-existing genetic variation.”7 And: “It’s kind of fun to find the mutations, because that’s the basic material of change.”12
Oh dear; deer mouse dogma
Those statements go to the nub of evolutionists’ core article-of-faith, their evolutionary dogma. They look to mutations as being evolution’s ‘engine’—the only source of the sort of new genetic information that could have turned mooted dawn-of-life microbes into deer mice during the supposed course of evolution. However, in no way does the appearance of pale mutant mice represent such a creative process. Note the malfunction of the already-existing pigment regulator, in this case involving the deletion of an amino acid.13,14 Evolutionists need to find mutations that create new enzymes and new metabolic pathways to prove the feasibility of their origins myth, but they find only mutations that modify already-existing features, as in this case. So the claim broadcast by the BBC excitedly portraying the sandy deer mouse of Nebraska as an ‘evolution icon’8 rings hollow. There is nothing here that supports the grand scheme of evolution at all.
The actual ‘big picture’
Overall, mutations are degrading the once-perfect biological processes (Genesis 1:31), which is right in line with the Bible’s account of the whole creation being cursed, very much now “in bondage to decay” (Romans 8:20–21). As these mutations accumulate, periodically we see that, though degraded from what was originally created, mutated genes can sometimes confer a survival advantage15 in this fallen world of carnivory and predation. How marvellous it will be when death and bloodshed will be no more—no wonder the whole creation waits in eager expectation (Romans 8:19, 22; 2 Peter 3:13; Revelation 21:4).
References and notes
- Nebraska’s sandhills are the most extensive sand dunes in North America, spreading for more than 50,000 square kilometres (20,000 square miles), over more than a quarter of the State. Return to text.
- Linnen, C.R., Poh, Y.-P., Peterson, B., Barrett, R., Larson, J., Jensen, J., Hoekstra, H., Adaptive evolution of multiple traits through multiple mutations at a single gene, Science 339(6125):1312–1316, 2013 | doi:10.1126/science.1233213. Return to text.
- Dice, L., Effectiveness of selection by owls of deer mice (Peromyzscus maniculatus) which contrast with their background, Contributions from the Laboratory of Vertebrate Biology University of Michigan 34:1–20, 1947. Return to text.
- Batten, D., The genetics of skin colour in people—something fishy? J. Creation 20(1):9–10, 2006; creation.com/genetics-fishy. Return to text.
- Linnen, C., Kingsley, E., Jensen, J., and Hoekstra, H., On the origin and spread of an adaptive allele in deer mice, Science 325(5944):1095–1098, 2009 | doi:10.1126/science.1175826. Return to text.
- Cf. Lightner, J.K., Colourful creature coats, Creation 28(4):33–34, 2006; creation.com/coats. Return to text.
- Bradt, S., Mice living in Sandhills quickly evolved lighter coloration, news.harvard.edu, 27 August 2009. Return to text.
- Walker, M., Mouse set to be ‘evolution icon’, bbc.co.uk, 27 August 2009. Return to text.
- E.g. see Catchpoole, D., The 3 Rs of evolution: Rearrange, Remove, Ruin—in other words, no evolution! Creation 35(2):47–49, 2013; creation.com/3rs. Return to text.
- Wieland, C., The Moth Files: An update on the Peppered Moth fiasco, Creation 25(1):14–15, 2002; creation.com/moths. Return to text.
- Pennisi, E., Evolutionary biology—how beach life favors blond mice, Science 325(5946):1330–1333, 2009. Return to text.
- Rosner, H., A colorful way to watch evolution in Nebraska’s sand dunes, nytimes.com, 8 August 2011. Return to text.
- Mutations overwhelmingly degrade genetic information, a downhill process. Whereas for microbes-to-mouse-and-man evolution to be true, evolutionists should be able to point to thousands of examples of information-gaining mutations, an uphill process, but they can’t. Note that sometimes diehard anti-creationists quibble over the definition of ‘information’. As information is foundationally an argument from probability, we might expect a few cases of trivial information increase (see the CMI DVD Understanding the Law of Decay, and creation.com/edge-evolution). But evolution requires encyclopedic amounts of new information. See Carter, R., Can mutations create new information? J. Creation 25(2):92–98, 2011; creation.com/new-info. Return to text.
- Williams, A., Evolution’s engine becomes evolution’s end! J. Creation 22(2):60–66, 2008; creation.com/evolutions-end. Return to text.
- While the pale mutation benefits the sandhill-dwelling deer mouse, in other species and contexts Agouti mutations might be of neutral value—populations can tolerate such mutations because they only affect coat colour, which in many circumstances doesn’t affect survival. In domestic animals, breeders have deliberately selected some of these mutations because people like the colours. See: Lightner, J., Ref. 6. However, in humans, loss-of-function mutations associated with the Agouti gene result in red hair, pale skin, inability to tan well in response to sun exposure, and an increased risk of skin cancer; Rees, J., The genetics of sun sensitivity in humans, American Journal of Human Genetics 75(5):739–751, 2004; Batten, D., Ref.4. Return to text.