Hybernating bats infected with Pseudogymnoascus destructans, showing white-nose syndrome. Credit: Government of Alberta/Flickr, CC BY-ND |
It's not a good day to be an intelligent [sic] design Creationist. In addition to that little problem with Creationism's supposedly all-loving creative deity apparently trying to find ways around the vaccines human medical science has developed against the nasty little SARS-CoV-2 virus it created to kill us or make us seriously sick, we now have this muddle over its treatment of bats, where for some reason it has created a fungus that has been designed to kill North American bats but not European bats!
To believers in intelligent [sic] design who know the facts about bat immune systems (and I accept that's probably very few if any) it must appear that their putative designer has some special affections for bats. Either that, or it wants them to have a robust immune system so they can act as laboratories and testbeds for producing novel coronaviruses like SARS-CoV-2.
As I said in my illustrated popular book, The Malevolent Designer:
But now we hear that creationism's putative intelligent [sic] designer seems to have turned on North American bats and has designed a special fungus, Pseudogymnoascus destructans to kill them with. The fatal disease this fungus produces in bats is known as 'white nose syndrome' and is responsible for killing millions of bats in North America, but not in Europe!Bats’ Superior Immune System.
We’ve already seen, in relation to SARS-CoV-2 (coronavirus) how bats appear to be immune to these viruses, so can act as incubators for new strains to arise, such as the one currently killing hundreds of thousands of people world-wide and wrecking economies (50).
Figure 48. Brown Long-eared bat, Plecotus auritus.
Now we learn that bats have an immune system that is much more effective than that of almost all other mammals, including humans (51). Although it is very good at recognising foreign RNA, in viruses for example, it is not so good at recognising foreign DNA, which dampens the inflammatory response that does so much damage, especially in humans infected with SARS-CoV-2. The genes that control those responses have probably (according to evolutionary biologists) been purified by natural selection because bats live in a wide range of ecological niches and exploit multiple prey species, including many different species of insects.
According to ID advocates, however, evolution by natural selection cannot account for these differences – they must have been intelligently designed.
So, as with the elephant’s immunity to cancer, Creationism’s putative designer chose to give all but bats an inferior immune system, the better to allow the pathogens it designed to do what they were designed to do – make us and other animals sick.
Now scientists working at the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), Forschungsverbund, Berlin, Germany have worked out how the hibernating European bats avoid becoming infected with P. destructans. The IZW news release explains:
Fungal diseases are a major threat to wildlife, sometimes resulting in significant population declines or even causing the extirpation of populations or species. White-nose syndrome, caused by the cold-loving fungus Pseudogymnoascus destructans, has become a major cause of death for hibernating bats in North America. European bats survive when infected by the same fungus during hibernation. What are the reasons for such a contrast in outcomes? A scientist team led by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) has now analysed the humoral innate immune defence of European greater mouse-eared bats to the fungus. In contrast to North American bats, European bats have sufficient baseline levels of key immune parameters and thus tolerate a certain level of infection throughout hibernation. The results are published in the journal "Developmental and Comparative Immunology". During infections caused by Pseudogymnoascus destructans (Pd), North American bats arouse frequently from hibernation to trigger a more elaborate immune response, whereas European bats remain dormant, owing, as the new results reveal, to their competent baseline immunity. Not being able to deal with the fungus by baseline immunity causes North American bats to deplete fat stores before the end of winter because of the need for additional and energetically expensive arousals, which ultimately leads to their starvation. European bats may also arouse once in a while when infected but their strong baseline immunity allows them to balance the tight energy budget better during winter hibernation.The teams research was published in the journal, Developmental & Comparative Immunology recently, sadly behind an expensive paywall.
For this investigation, the scientists went to hibernation sites in Germany and studied 61 mouse-eared bats (Myotis myotis) with varying levels of natural infections by Pseudogymnoascus destructans. The animals were divided into three groups according to the severity of fungal infections (asymptomatic, mild symptoms, severe infection). Body mass and skeletal body size of bats was measured and blood samples taken from torpid animals. In addition, the team monitored in other conspecifics how often infected animals arose from hibernation. “We could show that there is no link between infection and the frequency of waking up from hibernation in the European greater mouse-eared bat,” say Marcus Fritze and Christian C. Voigt, bat experts from the Department Evolutionary Ecology at Leibniz-IZW. “This is consistent with the idea that the fungus does not trigger an immune response in European hibernating bats but is rather kept under control by the bats’ baseline immunity.”
In contrast, North American bats such as little brown bats (Myotis lucifugus) arouse frequently when infected by the fungus to elicit an immune response. Frequent arousal and the immune response require energy and prematurely deplete the body’s fat stores before the winter has ended. The protein haptoglobin seems key in the bats’ fight against the fungus. Haptoglobin is an acute phase protein, which can be produced by bats without large metabolic costs. “Our results demonstrated the central role of haptoglobin in the defence against the fungus. Interestingly, baseline levels of this protein are sufficient to protect the European host against the fungus and there is no need to actively synthesise the protein during the torpid phase”, adds Gábor Á. Czirják, wildlife immunologist at the Department of Wildlife Diseases of the Leibniz-IZW.
[...]
These results add further evidence that there are differences in the defence strategies against the causative agent of white-nose syndrome in European and North American bat species. Tolerance strategies aim to limit the impact of the fungal infection on the health of animals. Resistance strategies, on the other hand, try to actively reduce the load of pathogens. “Tolerance strategies are effective, as the immune defences of hibernating European mouse-eared bats show,” Voigt summarises. “In North American bats, however, this ability is not present to a sufficient degree, possibly because the Pd fungus originated in Europe, giving European species a head start in developing efficient defence mechanisms.”
So, what should intelligent [sic] design advocates make of this situation? What we have here is similar to the one I pointed out in The Malevolent Designer, namely, if you accept the notion of intelligent [sic] design, you must accept that the supposed designer favoured bats over humans and all other mammals, so gave them a superior immune system that it could have given to all the others, but chose not to. Now we have the situation where this same putative designer appears to have given European bats a better immune system for coping with the fungus it designed to kill North American bats with.
Unless, of course, one accepts that these systems evolved under the pressure of natural selection by a mindless, amoral, natural process not requiring the intervention of a magic designer, and so absolve the putative designer of any responsibility for this situation.
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