Evolutionary medicine: Studying disease in a Darwinian context
Posted 7 April 2015 by Emily Thompson
What do Charles Darwin, wisdom teeth, and cancer have in common? They are all related to an emerging field called evolutionary medicine, the application of evolutionary principles to understanding why and how organisms get sick. Scientists in the field believe that an evolutionary perspective can help improve our diagnosis and treatment of disease.
In his keynote address at the inaugural meeting of the International Society for Evolution, Medicine, and Public Health (held March 19-21 in Tempe, AZ), Dr. Harvey Fineberg stated that an understanding of evolution is central to health. Fineberg, the former Dean of the Harvard School of Public Health, argued that an evolutionary viewpoint is necessary to explain structures and functions of the human body (like the fact that wisdom teeth were helpful in some way to our ancestors but serve no purpose now) and evolution can provide insight into diseases that develop and spread under evolutionary mechanisms, like infectious disease and cancer.
Antimicrobial resistance occurs when bacteria, viruses, and other infection-causing microorganisms evolve and develop mutations that enable them to resist drug therapies. Drug-resistant bacteria alone affect over two million Americans each year, according to the CDC. The process of microbial evolution follows the guiding principles of natural selection, so scientists can use their knowledge of evolution to understand how microbes attain resistance and perhaps even prevent it. For example, the current methods of treating bacterial infections target a mechanism of mutation called de novo mutation, but scientists have learned that antibiotic resistance mostly develops from a different method called horizontal gene transfer (Sterns, 2012), which suggests that we may need new therapies for bacterial infection.
Bacteria, like the mycobacteria above that cause tuberculosis, develop drug resistances by evolving and mutating under the influence of natural selection, just like all other organisms.
Image source: CDC
Evolutionary medicine has also started to play a role in cancer research. Some scientists are using an evolutionary background to understand how cancers develop, spread, and metastasize as well as to find effective treatments. For instance, a group of scientists is trying to understand how large animals with long lifespans, like the blue whale, have evolved and developed cancer suppression techniques that are reportedly 1000 times better than those of humans. Many hypotheses attempting to explain this phenomenon exist: the lower metabolic rate of large animals might lead to a lower mutation rate, or perhaps tumors are so much bigger in large animals that they are actually less likely to become malignant than smaller tumors (Nagy et. al., 2007). Whatever the explanation, understanding why and how large animals evolved to gain such effective tumor suppressor mechanisms could provide new therapies for cancer in humans. (Caulin and Maley, 2012.)
Additionally, studying deviations from physiological homeostasis in an evolutionary light may suggest that we need to make changes in how we treat some conditions. As Dr. Joe Alcock of the University of New Mexico commented at the ISEMPH meeting, what is defined as "normal" for the human body may be different depending on the conditions. For instance, doctors typically test patients for normal levels of hemoglobin (the molecule that transports oxygen in the blood) and glucose. But evolution has led some populations to adapt to unique environments and develop abnormal levels of these molecules; those living at higher altitudes are found to have a higher base level of hemoglobin than normal, pregnant women exhibit lower concentrations of hemoglobin as an adaptation to pregnancy, and patients with sepsis, a severe complication of infection, have elevated glucose levels, which may be an adaptive survival response. When doctors detect these abnormal glucose and hemoglobin levels, they will often treat the patients to return them to normal; however, Alcock argues that trying to restore every patient to one standard level may in fact do more harm than good if deviation from normalcy has an adaptive purpose.
The growth in the field of evolutionary biology, along with the sharp decline in genome-sequencing costs, has led to a new discipline of treating and diagnosing diseases called phylomedicine (Kumar et. al., 2011). Studying the differences between genomic information of healthy and diseased people, scientists have discovered many genetic diseases and the DNA variations associated with them. For example, mutations in the ALDH1L1 gene are associated with an increased risk of stroke (Williams et. al., 2014). However, simply analyzing individual genomes to discover the variations linked with certain diseases is inefficient and produces an extremely high volume of data, not all of which are significant. Instead, scientists can combine this analysis with a multi-species evolutionary perspective to narrow down the list and determine which genetic markers are associated with disease. Once these markers, like the ALDH1L1 gene, are identified, we can use them for diagnosis and as potential therapeutic targets.
Evolutionary principles can give insight into a wide range of medical topics: besides cancer and infectious disease, evolutionary thinking has shed light on other diseases like jaundice, influenza, and mental disorders (Nesse and Stearns, 2008). Also, studying the timeline of animal evolution and trait development can tell us which animals are most accurate models of human physiology for drug and device preclinical testing.
Members of the discipline see evolutionary medicine as having the potential to revolutionize the way we think about medicine. Adopting a new, evolutionary viewpoint on some of our most complex diseases could greatly benefit patients.
In our next post, we'll go into more detail about a specific clinical application of evolutionary medicine. Is there a topic you'd like to hear more about? Let us know in the comments section.This series is supported by NSF Grant #DBI-1356548 to RA Cartwright.
35 Comments
DS · 7 April 2015
This is exactly why evolution should be a part of the medical school curriculum. And that being the case, it should be part of the college curriculum and the high school curriculum as well. Those who choose to avoid the topic should find themselves at a distinct disadvantage when applying for medical school. Those who do not understand the topic should do poorly on medical school entrance exams. You can always choose to be ignorant, but if you want to be doctor you should be required to master the relevant information necessary to practice medicine. Needless to say, it would then become glaringly obvious how unprepared graduates from many religious institutions, some charter schools and even many home schoolers would be. If you want to fight a culture war, you should be prepared to pay the inevitable consequences.
gdavidson418 · 7 April 2015
Even the existence of pathogens fits nicely with opportunistic non-poof evolution, while design has never provided a reason. Do humans exist for the sake of Plasmodium falciparum, or really, what is the purpose?
Why does P. falciparum have an apicoplast? Because it evolved from a photosynthesizing organism (why, Behe, why?). And because we didn't, it may be that some of the genes that once were involved in photosynthesis in P. falciparum, now doing other things, may be vulnerable to drugs that wouldn't affect us overmuch.
I suppose Behe with his poof-evolution could say as much, it's just that nothing about it actually makes any sense as part of a design (why make it vulnerable if you're fond of said pathogen, and if you're not, why design it at all?). That is to say, any usefulness has to be borrowed from the findings of real science (evolutionary opportunism and adaptation), with "design" doing nothing but acting as a sop to their dislike of the real stuff.
Healing is king but evolutionism has no contribution to it. mere selection in species is unrelated to evolutionary biology's claims for biological origins. Its trivial selectionism within kinds or species. Teaching evolution to serious researchers who seek results for healing is a waste of time and will not do anything. in fact the chaos of selection on mutation etc etc couldn't anyways help with fixing things. by the way. creationists welcome wisdom teeth as a sign of human digestion before the flood. the bible, implies, man did not eat flesh/meat before the flood, a long time and so only afterward. Therefore our teeth would change to accomadate a new meat diet. Our wisdom teeth were before used more for eating non meant or the teeth at the front needed for meat eating put the famous pressure on the back ones and so, as recently for me, we get them dragged out. wisdom teeth make a creationist, YEC, point. Wise indeed.
DS · 8 April 2015
TIme for a dump to the bathroom wall. If you don't, you'll just get twenty more pages of crap like this from Byers, the king of crap.
RJ · 8 April 2015
As I have before, I urge that you do not move Byers weird rants. Let the undecided lurkers compare his comment to the ones above it and other ones likely to come. Also, people don't have to respond. Dude's words speak for themselves. Has anyone noticed an evolution in Byers? He seems more cocksure and a little crazier than years before.
Please remember that some people can't believe that anti-evolutionists like Byers exist. You have this blog to show them. For Byers, like most grassroots evolution deniers, is not stupid. But he is so far out of his depth he appears to be so when he writes here.
As to the topic at hand, I'll quietly listen to people who know what they are talking about, and not pretend to knowledge I don't have. Unlike some people! Keep it up Panda's Thumb.
DS · 8 April 2015
Actually, several people have already responded to the Byers crap on the bathroom wall. Of course he hates it there, so he isn't going to join in. All the better to roast his smarmy ass.
Just Bob · 8 April 2015
RJ said:
As I have before, I urge that you do not move Byers weird rants.
I think leaving his first post here, then a note that further posts and responses are on the BW is a good strategy. That way anyone can see how crazy he is, and if they care, they can look for more of the same in the loo. But letting him and his responders (of whom I admit I occasionally am one) turn a productive thread into Bobby World gets old fast.
Frank J · 8 April 2015
Just Bob said:
RJ said:
As I have before, I urge that you do not move Byers weird rants.
I think leaving his first post here, then a note that further posts and responses are on the BW is a good strategy. That way anyone can see how crazy he is, and if they care, they can look for more of the same in the loo. But letting him and his responders (of whom I admit I occasionally am one) turn a productive thread into Bobby World gets old fast.
It's also worth an occasional note to any new readers that anyone who seriously thinks that life is only 1000s of years old has issues with much more than evolution. In which case they would be expected to devote "equal time" to "challenging" evolution-deniers like DI Fellow Michael Behe, who concedes ~4 billion years of common descent. Readers are encouraged to check the DI's sites to verify the "equal time." Though they might find that YECs and Biblical OECs may be banned there (not just moved to a "Bathroom Wall") if they challenge ID. But if so, there are plenty of other places on the web where such people can vent their dissatisfaction with ID. Including on PT's own Bathroom Wall.
If there is nothing close to "equal time," readers can reasonably suspect that the person does not really take young life or "kinds" seriously, but merely has an emotional objection to some "evolutionism" caricature. If they're not just a Loki troll.
ashleyhr · 8 April 2015
I see that young Earth creationists have just attacked a recent paper concerning horizontal gene transfer in the animal kingdom (metazoans) entitled 'Expression of multiple horizontally acquired genes is a hallmark of both vertebrate and invertebrate genomes': http://genomebiology.com/2015/16/1/50 (I've only read the Abstract) http://www.icr.org/article/8673 Tomkins claims: "... evolutionary biologists constantly resort to fictional stories cloaked in technical terminology to escape the straightforward conclusion that the genomes of different creatures were purposefully crafted".
Robert Byers · 8 April 2015
Then lets get down to a real question. How can medical investigation claim to be using evolutionary concepts when all they do is work within a species obserrving selection? A creationist, YEC/ID, would do exactly the same thing. It shows me the creationist criticism that evolutionary biology is useless in real biology and so medicine iS hitting home. so they invoke evolution helps explain/healing concepts .
RAJ · 9 April 2015
Thank you very much for starting this series. I am a researcher from Germany working on respiratory diseases, particularly chronic obstructive pulmonary disease (COPD), a common consequence of smoking. Similar to other diseases, there is tissue remodelling and destruction, especially in lung emphysema. Currently we do not have other than symptomatic therapies for COPD. Since a number of years I have been interested in therapeutic options involving regeneration. Such options would also be of interest for other organs of comparable complexity, e.g. the kidney.
It is known that the regenerative potential varies between species. For example, mice and rats can regenerate lung alveoli but not airways. There is a report from the 1950s that newts and the axolotl can regenerate a whole lung. In contrast, regeneration of complex structures does not seem possible in humans, except for skin, mucosa etc and - to a limited extent - for the liver as well as - under special conditions - for fingertips. Mammals such as cervids can generate a structure as complex as a pair of antlers every year, although de novo and not by regenerating within a pre-existing framework. It might be that specific constraints in the human genome prohibit regeneration except in special cases, and I have looked for a comparison of genomes in order to understand why certain species can regenerate and others not, but without conclusive result. There seems to be no general pattern, possibly due to evolutionary tinkering, as even closely related species can show differences in their regenerative capacity. Still it seems to me that the look for âblocksâ by a comparison of genomes could be worthwhile. Of course, there are probably also other constraints, ranging from micromechanics to specific cellular environments during development. Despite all these complications, even a âtinyâ goal such as induced regeneration of lung alveoli would be of great benefit for COPD patients.
The issue might also be of interest with regard to classical concepts of evolution. For example, it is tempting to ask why a âcheapâ organim with an r-strategy such as a newt can regenerate so much, i.e. âsaveâ the individual, and a âpreciousâ organism such as a mammal with an K-strategy can not but is doomed. Prima facie this seems surprising.
I would be glad if you could give some of your thoughts about this link between evolution and medicine. Possibly there are interesting results which I missed, possibly the comparative analysis will not lead very far as the conditions in different species are too specific.
Just Bob · 9 April 2015
The perfect ironic juxtaposition: Byers and RAJ.
eric · 9 April 2015
RAJ said:
The issue might also be of interest with regard to classical concepts of evolution. For example, it is tempting to ask why a âcheapâ organim with an r-strategy such as a newt can regenerate so much, i.e. âsaveâ the individual, and a âpreciousâ organism such as a mammal with an K-strategy can not but is doomed. Prima facie this seems surprising.
Hmm, I always thought it was relatively unsurprising. K-strategy parents keep their offspring away from danger during development, r-strategy parents do not. Adaptations that allow offspring to recover from serious injury will be less valuable in the former organisms because they can be expected to suffer fewer serious injuries growing up. Very much like the vitamin C thing: if an organism rarely experiences a lack of vitamin C (or loss of a foot) in its environment, we can expect random mutation will eventually eliminate the genetic structure that allows for production of vitamin C (and new feet).
There is also timing to contend with: regenerative capabilities are only a positive adaptation if they give you a survival advantage "in time." If you need that foot tomorrow and it takes a month to regrow, you might as well not have the ability to regrow it. This would lead us to expect that high metabolism animals and animals without the ability to hibernate or sleep for a long time might gain less from a regenerative adaptation compared to low metabolism animals. Example: if I have to go out and hunt and run every day just to survive, the ability to regrow a foot over three months is not a very positive adaptation. OTOH if I only need to hunt one day a week or month or I can hibernate for 3 months straight in a pinch, a 3-month "critical limb" regenerative capability allows me to survive (and have more kids). So possibly one reason apes can regrow fingertips but not whole hands and such is that apes can get by without a fingertip for the time it takes them to regrow it. But if they (ahem, we) lost a whole hand, they'd generally die before they could regrow it.
RAJ · 9 April 2015
@eric
Thanks for the detailed response. I used the contrast K vs r primarily to illustrate sort of a paradox, as I have been asked just this after presentations. For me the question remains of interest why e.g. newts can regenerate so much, not only after serious injuries but also internally. Is it an adaptation or a byproduct of some other phenomenon? I am not aware of studies addressing the question whether their capability is of relevance in the natural environment. Newts can live many years, but it remains an open issue whether it is important for them e.g. to be capable of regenerating parts of the heart.
But for me the major question is how is it achieved and how it is not achieved in other organisms? Naturally, for COPD and its co-morbidities "internal injuries" regarding the lung and the heart are of primary interest. To me it is not clear whether the regenerative potential regarding these organs has much to do with the presence or absence of protection by the parents among different organims, and your argument of lack of usefulness of partially regrown organs does not seem to apply. What should be the problem with a gradual regrowing of a damaged lung? As an additional aspect, I think, one has to consider life expectancy and in particular age which interferes with regenerative capacities.
Based on these considerations I am not so much interested in explaining the presence or absence of regeneration as an adaptation but in understanding which genomic changes in the course of evolution (plus potentially epigenetic factors) have led to lack of capabilities. Insight into this could guide novel regenerative therapies aiming at reactivation of deactivated pathways. The idea is that e.g. genetic moduli for alveolar regeneration are more or less âaccessibleâ even in adult mice but not in adult humans. Could it be simply a result of differences in life expectancy and/or age, as small children probably can regrow alveoli, to a limited extent?
A different question is, why - from the point of view of adaptation - humans showing a much larger life expectancy than mice cannot regenerate parts of the lung that e.g. might have been damaged by smoke within caves, in the course of infections etc. We know from studies including those of ancient samples that under "natural conditions" humans can acquire degenerative disorders even in relatively young age. Is the (partial) lack of regeneration a price necessarily to be paid for the complex genetic and epigenetic pathways of human development? Can we re-open morphogenetic moduli without significant risk, particularly after learning from different animals? So itâs more a comparative approach to evolutionary diversity.
Again thank you for your response.
callahanpb · 9 April 2015
RAJ said:
Since a number of years I have been interested in therapeutic options involving regeneration. Such options would also be of interest for other organs of comparable complexity, e.g. the kidney.
Since you mention the kidney, do you know of any animals that can regenerate nephrons? Doing this in humans would be the Holy Grail of kidney treatment I think.
RAJ · 9 April 2015
@callahanpb
I agree, it would be at least as important as for COPD which is, however, already among the leading causes of death worldwide.
There is, of course, the newt but surprisingly very very few data (as for the lung), see Scadding SR, Liversage RA. Studies on the response of the adult newt kidney to partial nephrectomy. Am J Anat 1974 Jul;140(3):349-67.
There are rats and mice (which can also regenerate the liver much better than humans can), see e.g. Yang HC, Liu SJ, Fogo AB. Kidney regeneration in mammals. Nephron Exp Nephrol 2014;126(2):50.
And, who would not expect this, the zebrafish, see e.g. Davidson AJ. Kidney regeneration in fish. Nephron Exp Nephrol 2014;126(2):45.
There are also people working on supportive drugs (which can also have an effect in rodents regarding lung regeneration), see e.g. Gagliardini E, Benigni A. Drugs to foster kidney regeneration in experimental animals and humans. Nephron Exp Nephrol 2014;126(2):91.
But there is also the line of bioengineering via scaffolding etc which, in my opinion, is better suited for the kidney than for the lung, see Zambon JP, Magalhaes RS, Ko I, Ross CL, Orlando G, Peloso A, Atala A, Yoo JJ. Kidney regeneration: Where we are and future perspectives. World J Nephrol 2014 Aug 6;3(3):24-30.
I hope that is informative for you. I do not know of researchers following the approach which I have sketched for the lung.
Kind regards
ksplawn · 9 April 2015
I've heard that cancers can become more aggressive over the course of a patient's treatment, or return very aggressively years after remission, because the cancer cells that respond sensitively to the treatment are killed off while any malignant cells that have some sort of resistance remain behind to reproduce without competition. This triggers a round of evolution in the populations of cancer cells that promotes takeover by more aggressive and resistant strains that can fill in the niche left by more benign and sensitive ones. It was analogized to agricultural pests vs. pesticides and how we can inadvertently promote the spread of more resistant pests, except this process would play out within a single patient (for obvious reasons).
RAJ · 9 April 2015
@ksplawn
Yes, this is a major problem. One of the modern strategies, informed by systems biology, is to design drug therapies that hit multiple pathways at once or in succession so that as many âways of escapeâ as possible are no more accessible for the tumour cells.
harold · 9 April 2015
I massively agree with this article. Evolutionary biology is central to biomedical science, and pops up in medicine all the time. It is possible to practice competent medicine at an applied level without this understanding, but that would create cognitive dissonance.
I am going to take minimal issue with something unfair and misleading in the article.
But evolution has led some populations to adapt to unique environments and develop abnormal levels of these molecules; those living at higher altitudes are found to have a higher base level of hemoglobin than normal, pregnant women exhibit lower concentrations of hemoglobin as an adaptation to pregnancy, and patients with sepsis, a severe complication of infection, have elevated glucose levels, which may be an adaptive survival response. When doctors detect these abnormal glucose and hemoglobin levels, they will often treat the patients to return them to normal; however, Alcock argues that trying to restore every patient to one standard level may in fact do more harm than good if deviation from normalcy has an adaptive purpose.
It would be total malpractice to "treat" the healthy variations in blood hemoglobin concentration that can occur with altitude or pregnancy and no-one ever does. Sepsis is treated with antibiotics and respiratory and circulatory support as needed. Sepsis essentially means death without these treatments. High serum glucose in sepsis is probably not adaptive. If it isn't life threatening it's probably irrelevant. At any rate, what you do with a septic patient is kill the organisms that are killing them, and support them through it, because their organs are collapsing.
We also don't try to make strong people weaker, give drugs that cause confusion to top students to make them more "normal", order patients at a healthy weight to become fatter so that they can be closer to the population norm, or anything else like that.
In fact in medicine we actually don't give a damn about "normal" parameters at all. That's just an anachronistic term. What we care about is "optimal" levels for health and well-being, based on the evidence. Optimal may be different for different people, a broad flexible range, or may be a narrow range for everyone, depending on what parameter we are talking about. Chronically high blood glucose is almost NEVER optimal, by the way.
(I do use the terms "normal", or even worse, "negative", pretty often as a pathologist, for conventional reasons. Those are just another example of ingrained suboptimal English use in the sciences. Everyone knows I mean "I can't see anything wrong" when I use those terms. "Normal" and "optimal" are not the same. "Negative" is a poor term for "healthy". Those are just conventions.)
There may well be some good examples of physicians mistakenly treating an adaptive deviation from the population mean. I've never seen it, but it may exist. However, these are not such examples.
Overall though, evolution is central to modern scientific medicine, and becoming more so.
harold · 9 April 2015
ksplawn said:
I've heard that cancers can become more aggressive over the course of a patient's treatment, or return very aggressively years after remission, because the cancer cells that respond sensitively to the treatment are killed off while any malignant cells that have some sort of resistance remain behind to reproduce without competition. This triggers a round of evolution in the populations of cancer cells that promotes takeover by more aggressive and resistant strains that can fill in the niche left by more benign and sensitive ones. It was analogized to agricultural pests vs. pesticides and how we can inadvertently promote the spread of more resistant pests, except this process would play out within a single patient (for obvious reasons).
Yes, of course. Note that the treatment is still net beneficial. Without the treatment the patient would just be killed by the original clone of cells. (Spontaneous remissions of invasive cancers are very rare and mostly reflect misdiagnosis, rather than actual spontaneous remission.) By treating the cancer, we kill most of the cancer and buy the patient more time. In some cases, in some types of cancer, we do completely cure them by any reasonable standard. But yes, often some resistant cells survive and cause a relapse when they have multiplied to critical volume.
This is an argument in favor of developing even better treatments.
It isn't an argument against treating. The one thing worse than being killed by resistant cells a year after your remission, is to be killed a year earlier with no remission.
callahanpb · 9 April 2015
RAJ said:
There are also people working on supportive drugs (which can also have an effect in rodents regarding lung regeneration), see e.g. Gagliardini E, Benigni A. Drugs to foster kidney regeneration in experimental animals and humans. Nephron Exp Nephrol 2014;126(2):91.
But there is also the line of bioengineering via scaffolding etc which, in my opinion, is better suited for the kidney than for the lung, see Zambon JP, Magalhaes RS, Ko I, Ross CL, Orlando G, Peloso A, Atala A, Yoo JJ. Kidney regeneration: Where we are and future perspectives. World J Nephrol 2014 Aug 6;3(3):24-30.
Thanks. I'll look up both of these. I have read some news articles about generating kidneys using decellularized pig kidneys (or unusable human kidneys) as scaffolds. Is that that same thing? I couldn't determine how far along this kind of research is. It came as news to me very recently that scarred kidney tissue doesn't heal. (You can probably guess that I have a personal stake in this--without going into details, anyway my own kidneys are fine.)
It is not that surprising that some organs don't regenerate, but I do find it a little surprising that it can differ so much by species. I just wonder whether regeneration might have more survival value to some species than others, or whether it is just less problematic for some reason.
Robert Byers · 9 April 2015
harold said:
I massively agree with this article. Evolutionary biology is central to biomedical science, and pops up in medicine all the time. It is possible to practice competent medicine at an applied level without this understanding, but that would create cognitive dissonance.
I am going to take minimal issue with something unfair and misleading in the article.
But evolution has led some populations to adapt to unique environments and develop abnormal levels of these molecules; those living at higher altitudes are found to have a higher base level of hemoglobin than normal, pregnant women exhibit lower concentrations of hemoglobin as an adaptation to pregnancy, and patients with sepsis, a severe complication of infection, have elevated glucose levels, which may be an adaptive survival response. When doctors detect these abnormal glucose and hemoglobin levels, they will often treat the patients to return them to normal; however, Alcock argues that trying to restore every patient to one standard level may in fact do more harm than good if deviation from normalcy has an adaptive purpose.
It would be total malpractice to "treat" the healthy variations in blood hemoglobin concentration that can occur with altitude or pregnancy and no-one ever does. Sepsis is treated with antibiotics and respiratory and circulatory support as needed. Sepsis essentially means death without these treatments. High serum glucose in sepsis is probably not adaptive. If it isn't life threatening it's probably irrelevant. At any rate, what you do with a septic patient is kill the organisms that are killing them, and support them through it, because their organs are collapsing.
We also don't try to make strong people weaker, give drugs that cause confusion to top students to make them more "normal", order patients at a healthy weight to become fatter so that they can be closer to the population norm, or anything else like that.
In fact in medicine we actually don't give a damn about "normal" parameters at all. That's just an anachronistic term. What we care about is "optimal" levels for health and well-being, based on the evidence. Optimal may be different for different people, a broad flexible range, or may be a narrow range for everyone, depending on what parameter we are talking about. Chronically high blood glucose is almost NEVER optimal, by the way.
(I do use the terms "normal", or even worse, "negative", pretty often as a pathologist, for conventional reasons. Those are just another example of ingrained suboptimal English use in the sciences. Everyone knows I mean "I can't see anything wrong" when I use those terms. "Normal" and "optimal" are not the same. "Negative" is a poor term for "healthy". Those are just conventions.)
There may well be some good examples of physicians mistakenly treating an adaptive deviation from the population mean. I've never seen it, but it may exist. However, these are not such examples.
Overall though, evolution is central to modern scientific medicine, and becoming more so.
How so? i say evolution has done, will do none, gains for healing or understanding how to fix things.
Evolution is not true. Selection in populations is okay but thats in species. Creationism welcomes that.
Nobody needs to know or agree with evolution to do medicine or research on existing biological systems.
Any claims of origins of biological systems is not present biology and present biology is all one works with.
I welcome all healing and need a bit myself. But evolutionary biology is irrelevant unless one can show otherwise.
RAJ · 10 April 2015
@callahanpb
There are several strategies. One of them is to use cells from the individual patient to generate a kidney or parts of it externally using scaffolds plus bioreactor and then to implant the tissue or organ. Kidney implanatation is certainly more feasible than implantation of the lung therefore this makes sense for the kidney. The candidates are patients with severe disease.
This might change with the approach of promoting âin situâ regeneration. Who should be the primary target for this? Possibly not patients with advanced disease and largely destructed organs but patients with mild to moderate however progressive disease. These patients could offer enough residual morphological and functional structure to support in situ regeneration. This aim is much more modest that de novo generation. However, it could be difficult to convince others, particularly health care providers, that this is a reasonable decision for treatment. Certainly we would need large long-term studies.
To illustrate this point: There is a genetic disorder, alpha-1-antitrypsin deficiency, which is associated with low levels of an important anti-protease. This can promote the development of severe lung emphysema. The substitution therapy is extremely expensive and its effectiveness often questioned but we do not have a plausible alternative. If the therapy is paid by insurances at all, then only in patients with advanced disease. In my opinion, much better candidates would be patients with beginning lung disorder in whom you might have a greater chance to inhibit or slow down the fatal disease process. In this case itâs about destruction but the argument for regeneration would be similar.
James Downard · 10 April 2015
This fine post (and the comments thread attached) is entering my #TIP www.tortucan.wordpress.com/ counter-creationism resource (read Nick Matke's post here on Pandas on what #TIP is about and how to support it http://pandasthumb.org/archives/2015/03/troubles-in-par.html#more), part of the ongoing contrast between the vacuous nothing that is YEC/ID on this front and the detailed evidence focused evolutionary science.
Naturally antievolutionists rationalize and even attempt to coopt snippets of the data set (as YECer Tomkins does for AiG) but there is only so far one can push water uphill without it sloshing back down again. Byers comments are most illustrative of the rationalizing mind at play, but the work will still be done by the scientific community, and as in so many other areas of science (think paleontology or developmental biology) increasingly evolution will illuminate and guide that study.
Steve Schaffner · 10 April 2015
"But evolution has led some populations to adapt to unique environments and develop abnormal levels of these molecules; those living at higher altitudes are found to have a higher base level of hemoglobin than normal..."
Not in the Himalayas: base hemoglobin concentration there is similar to that found in sea level populations.
harold · 11 April 2015
Steve Schaffner said:
"But evolution has led some populations to adapt to unique environments and develop abnormal levels of these molecules; those living at higher altitudes are found to have a higher base level of hemoglobin than normal..."
Not in the Himalayas: base hemoglobin concentration there is similar to that found in sea level populations.
Adaptation to altitude is complex. A healthy person from a low altitude will often experience a modest increase in blood hemoglobin concentration/hematocrit upon moving to a higher altitude.
You cannot increase blood hemoglobin concentration too much, because hemoglobin is carried by red blood cells. Too many red blood cells will lead to dangerous increase in blood viscosity. However, some adjustment is possible.
Long term Alpine populations may have adaptations such as hemoglobin alleles that more efficiently bind oxygen, and/or may have somewhat higher mean hemoglobin concentration in blood.
Another confounding variable is that endurance training or similar things may increase blood volume to some degree. A person may have more hemoglobin in circulation, but not a higher concentration. If more blood oxygenates a tissue per unit time, this may also be adaptive. This is fairly common.
MFMartins · 19 April 2015
I find DR. Joe Alcock's idea to be fascinating, the idea that modern medicine could be interfering with the natural progress of evolution. When we think of it a difference in ones genome to the norm is basically a mutation and favourable mutations bring about evolution over time so cancelling out or fixing the change could be a serious problem. This could just be another case of man ending mankind...
Does anyone know of any other research on this matter, I would like to read more about it. (u15202390)
harold · 20 April 2015
I find DR. Joe Alcockâs idea to be fascinating, the idea that modern medicine could be interfering with the natural progress of evolution.
Certainly some people live to reproduce who would have died or been sterile without modern medicine.
However, this is part of the natural process of evolution. Humans are natural. The human brain is natural.
Modern medicine is no more interfering with the natural process of evolution than stone tools, control of fire, and invention of clothing interfered with the process of evolution. In fact its effects are massively less powerful that those were. But it's all natural evolution. Unless you argue that crow intelligence is interfering with natural crow evolution, too, or some such thing, which would be absurd.
However, please feel free to refuse modern medical care yourself, if that is your personal preference.
When we think of it a difference in ones genome to the norm is basically a mutation
This is at best very poorly worded. A mutation is a very simple thing. It is a difference, after replication, between a parent nucleic acid sequence and the "daughter" nucleic acid sequence. To that some might add that a spontaneous change in the base sequence of a nucleic acid sequence, even when not reproducing, is a mutation.
Whether something is "the norm" is entirely subjective.
If a sickle cell hemoglobin allele is undergoing replication and the new allele has a slightly different nucleic acid sequence, such that it is no longer a sickle allele, that is an example of a mutation, even though the mutation led to reversion of a harmful allele.
In medicine we do create confusion by always referring to harmful alleles as "mutant" alleles. We mean that we think that they originated as mutations of non-harmful alleles, but we use the terminology a bit imprecisely, I concede.
and favourable mutations bring about evolution over time so cancelling out or fixing the change could be a serious problem. This could just be another case of man ending mankindâ¦
There is a lot wrong with this. It is hard to no where to begin. First of all, what is favorable depends on the environmental context.
Second of all, modern medicine does not "cancel out" positive adaptations. As I noted above, and I will concede to considerable irritation at needing to make this obvious point again, we don't effing treat deviations from the population mean or "abnormalities", we treat things that patients are complaining about, or sometimes, things we detect that we know will cause them serious complaints in the future if we don't treat them now. If we treat asymptomatic things like blood pressure we try to make them optimal to avoid future problems that would make patients unhappy. Patients want to be alive and feel healthy and that's what medicine helps them with. I'm quite stunned that anyone would be stupid enough to believe that other people are stupid enough to go to doctors if what we did was to ignore patient wishes and irrationally impose some kind of population mean determined "normality". There's plenty to criticize in the US medical system, so why don't people stick to accurate criticisms? This "doctors blindly try to make you 'normal' no matter what is best" nonsense is one of the worst straw man constructions I have seen in a long time. Let's leave that type of thing to the creationists.
Modern humans from industrial countries mainly aren't very good at hunter gathering, with numerous exceptions, but to think that this is due to genetics shows great naivete of population genetics. Medicine does allow some people with genetic problems to survive, but it does not significantly select against adaptations. We have about as much genetic resistance to infectious disease as our medieval ancestors, and maybe more. We have antibiotics and sanitation to help, but there is no mechanism by which treating someone with antibiotics would change their germline DNA and make their natural resistance mechanisms go away. I hope that reassures you.
John · 20 April 2015
I just stumbled upon this now. Emily, thanks for writing a great blog post and am looking forward to reading more from you in the future. I am reminded how a noted British epidemiologist showed a picture of a young Charles Darwin after the HMS Beagle voyage, declared that he was the founder of our science, and no one in the room except for yours truly could raise his hand when he asked who that fellow was. (This was at a faculty lecture he gave when he was a visiting professor at an epidemiology department I worked for years ago .) The reason why I am saying this is that more people should realize that epidemiology, as well as evolutionary medicine, is based on Darwin's work on Natural Selection.
harold · 20 April 2015
John said:
I just stumbled upon this now. Emily, thanks for writing a great blog post and am looking forward to reading more from you in the future. I am reminded how a noted British epidemiologist showed a picture of a young Charles Darwin after the HMS Beagle voyage, declared that he was the founder of our science, and no one in the room except for yours truly could raise his hand when he asked who that fellow was. (This was at a faculty lecture he gave when he was a visiting professor at an epidemiology department I worked for years ago .) The reason why I am saying this is that more people should realize that epidemiology, as well as evolutionary medicine, is based on Darwin's work on Natural Selection.
Although I have been complaining a little about the grossly incorrect suggestion that contemporary physicians treat healthy asymptomatic variation, overall, the blog post is excellent.
We don't currently need to delve into the most advanced levels of bioinformatics and population genetics to practice medicine, but the theory of evolution is incredibly useful for medicine. It helps explain, right off the top of my head, anatomy, basic biochemistry, development of resistance to antibiotics by microbes, development of resistance to chemotherapy by cancer cells, parasite life cycles, and numerous other things.
John · 20 April 2015
harold said:
John said:
I just stumbled upon this now. Emily, thanks for writing a great blog post and am looking forward to reading more from you in the future. I am reminded how a noted British epidemiologist showed a picture of a young Charles Darwin after the HMS Beagle voyage, declared that he was the founder of our science, and no one in the room except for yours truly could raise his hand when he asked who that fellow was. (This was at a faculty lecture he gave when he was a visiting professor at an epidemiology department I worked for years ago .) The reason why I am saying this is that more people should realize that epidemiology, as well as evolutionary medicine, is based on Darwin's work on Natural Selection.
Although I have been complaining a little about the grossly incorrect suggestion that contemporary physicians treat healthy asymptomatic variation, overall, the blog post is excellent.
We don't currently need to delve into the most advanced levels of bioinformatics and population genetics to practice medicine, but the theory of evolution is incredibly useful for medicine. It helps explain, right off the top of my head, anatomy, basic biochemistry, development of resistance to antibiotics by microbes, development of resistance to chemotherapy by cancer cells, parasite life cycles, and numerous other things.
Exactly. I am sure I am not alone here in expressing my full agreement with your observation.
TomS · 20 April 2015
Perhaps there are people who do not think that explaining the medical (and agricultural, ecological, geological, etc.) world is useful.
harold · 21 April 2015
TomS said:
Perhaps there are people who do not think that explaining the medical (and agricultural, ecological, geological, etc.) world is useful.
There are plenty, but they don't cause a lot of problems.
The problems come from people who demand certain explanations in order to rationalize a particular religious/social/political ideology.
For example, you start out wanting to discriminate against gay people. Maybe you're not gay, or at least self-identify as not gay and it makes you feel good about yourself to see somebody else get a hard time.
So you hear that AIDS is somehow associated with gay men and you proudly announce that it is caused by God to punish gays, or you take the more dissembling approach and blame it on "lifestyle".
Then science tells you it's caused by a virus, and it has nothing to do with being gay. It's true that certain types of unprotected sex that were especially associated with the gay male community circa 1980 are one risk factor, but the virus couldn't care less whether you're gay or not, and it can also be spread by blood transfusions, non-sterile injections, heterosexual sex, or from pregnant mother to child.
So what do you do? You deny the scientific explanation, and obsessively stick to your own wrong explanation, because your wrong explanation rationalizes the bigoted ideology you wish to adhere to.
Another group of self-serving ideologues who deny HIV are professional quacks who sell snake oil to desperate people and call it "natural healing", of course. The idea is pretty much the same.
Tomato Addict · 27 April 2015
If anyone was not already aware of this:
J Mol Med (Berl). 2012 May;90(5):481-94. Epub 2012 Apr 27.
Nothing in medicine makes sense, except in the light of evolution.
Varki
http://www.ncbi.nlm.nih.gov/pubmed/22538272
John · 29 April 2015
Tomato Addict said:
If anyone was not already aware of this:
J Mol Med (Berl). 2012 May;90(5):481-94. Epub 2012 Apr 27.
Nothing in medicine makes sense, except in the light of evolution.
Varki
http://www.ncbi.nlm.nih.gov/pubmed/22538272
35 Comments
DS · 7 April 2015
This is exactly why evolution should be a part of the medical school curriculum. And that being the case, it should be part of the college curriculum and the high school curriculum as well. Those who choose to avoid the topic should find themselves at a distinct disadvantage when applying for medical school. Those who do not understand the topic should do poorly on medical school entrance exams. You can always choose to be ignorant, but if you want to be doctor you should be required to master the relevant information necessary to practice medicine. Needless to say, it would then become glaringly obvious how unprepared graduates from many religious institutions, some charter schools and even many home schoolers would be. If you want to fight a culture war, you should be prepared to pay the inevitable consequences.
gdavidson418 · 7 April 2015
Even the existence of pathogens fits nicely with opportunistic non-poof evolution, while design has never provided a reason. Do humans exist for the sake of Plasmodium falciparum, or really, what is the purpose?
Why does P. falciparum have an apicoplast? Because it evolved from a photosynthesizing organism (why, Behe, why?). And because we didn't, it may be that some of the genes that once were involved in photosynthesis in P. falciparum, now doing other things, may be vulnerable to drugs that wouldn't affect us overmuch.
I suppose Behe with his poof-evolution could say as much, it's just that nothing about it actually makes any sense as part of a design (why make it vulnerable if you're fond of said pathogen, and if you're not, why design it at all?). That is to say, any usefulness has to be borrowed from the findings of real science (evolutionary opportunism and adaptation), with "design" doing nothing but acting as a sop to their dislike of the real stuff.
Glen DAvidson
Robert Byers · 7 April 2015
Healing is king but evolutionism has no contribution to it. mere selection in species is unrelated to evolutionary biology's claims for biological origins.
Its trivial selectionism within kinds or species.
Teaching evolution to serious researchers who seek results for healing is a waste of time and will not do anything.
in fact the chaos of selection on mutation etc etc couldn't anyways help with fixing things.
by the way. creationists welcome wisdom teeth as a sign of human digestion before the flood. the bible, implies, man did not eat flesh/meat before the flood, a long time and so only afterward.
Therefore our teeth would change to accomadate a new meat diet. Our wisdom teeth were before used more for eating non meant or the teeth at the front needed for meat eating put the famous pressure on the back ones and so, as recently for me, we get them dragged out.
wisdom teeth make a creationist, YEC, point. Wise indeed.
DS · 8 April 2015
TIme for a dump to the bathroom wall. If you don't, you'll just get twenty more pages of crap like this from Byers, the king of crap.
RJ · 8 April 2015
As I have before, I urge that you do not move Byers weird rants. Let the undecided lurkers compare his comment to the ones above it and other ones likely to come. Also, people don't have to respond. Dude's words speak for themselves. Has anyone noticed an evolution in Byers? He seems more cocksure and a little crazier than years before.
Please remember that some people can't believe that anti-evolutionists like Byers exist. You have this blog to show them. For Byers, like most grassroots evolution deniers, is not stupid. But he is so far out of his depth he appears to be so when he writes here.
As to the topic at hand, I'll quietly listen to people who know what they are talking about, and not pretend to knowledge I don't have. Unlike some people! Keep it up Panda's Thumb.
DS · 8 April 2015
Actually, several people have already responded to the Byers crap on the bathroom wall. Of course he hates it there, so he isn't going to join in. All the better to roast his smarmy ass.
Just Bob · 8 April 2015
Frank J · 8 April 2015
ashleyhr · 8 April 2015
I see that young Earth creationists have just attacked a recent paper concerning horizontal gene transfer in the animal kingdom (metazoans) entitled 'Expression of multiple horizontally acquired genes is a hallmark of both vertebrate and invertebrate genomes':
http://genomebiology.com/2015/16/1/50 (I've only read the Abstract)
http://www.icr.org/article/8673
Tomkins claims: "... evolutionary biologists constantly resort to fictional stories cloaked in technical terminology to escape the straightforward conclusion that the genomes of different creatures were purposefully crafted".
Robert Byers · 8 April 2015
Then lets get down to a real question.
How can medical investigation claim to be using evolutionary concepts when all they do is work within a species obserrving selection? A creationist, YEC/ID, would do exactly the same thing.
It shows me the creationist criticism that evolutionary biology is useless in real biology and so medicine iS hitting home. so they invoke evolution helps explain/healing concepts .
RAJ · 9 April 2015
Thank you very much for starting this series. I am a researcher from Germany working on respiratory diseases, particularly chronic obstructive pulmonary disease (COPD), a common consequence of smoking. Similar to other diseases, there is tissue remodelling and destruction, especially in lung emphysema. Currently we do not have other than symptomatic therapies for COPD. Since a number of years I have been interested in therapeutic options involving regeneration. Such options would also be of interest for other organs of comparable complexity, e.g. the kidney.
It is known that the regenerative potential varies between species. For example, mice and rats can regenerate lung alveoli but not airways. There is a report from the 1950s that newts and the axolotl can regenerate a whole lung. In contrast, regeneration of complex structures does not seem possible in humans, except for skin, mucosa etc and - to a limited extent - for the liver as well as - under special conditions - for fingertips. Mammals such as cervids can generate a structure as complex as a pair of antlers every year, although de novo and not by regenerating within a pre-existing framework. It might be that specific constraints in the human genome prohibit regeneration except in special cases, and I have looked for a comparison of genomes in order to understand why certain species can regenerate and others not, but without conclusive result. There seems to be no general pattern, possibly due to evolutionary tinkering, as even closely related species can show differences in their regenerative capacity. Still it seems to me that the look for âblocksâ by a comparison of genomes could be worthwhile. Of course, there are probably also other constraints, ranging from micromechanics to specific cellular environments during development. Despite all these complications, even a âtinyâ goal such as induced regeneration of lung alveoli would be of great benefit for COPD patients.
The issue might also be of interest with regard to classical concepts of evolution. For example, it is tempting to ask why a âcheapâ organim with an r-strategy such as a newt can regenerate so much, i.e. âsaveâ the individual, and a âpreciousâ organism such as a mammal with an K-strategy can not but is doomed. Prima facie this seems surprising.
I would be glad if you could give some of your thoughts about this link between evolution and medicine. Possibly there are interesting results which I missed, possibly the comparative analysis will not lead very far as the conditions in different species are too specific.
Just Bob · 9 April 2015
The perfect ironic juxtaposition: Byers and RAJ.
eric · 9 April 2015
RAJ · 9 April 2015
@eric
Thanks for the detailed response. I used the contrast K vs r primarily to illustrate sort of a paradox, as I have been asked just this after presentations. For me the question remains of interest why e.g. newts can regenerate so much, not only after serious injuries but also internally. Is it an adaptation or a byproduct of some other phenomenon? I am not aware of studies addressing the question whether their capability is of relevance in the natural environment. Newts can live many years, but it remains an open issue whether it is important for them e.g. to be capable of regenerating parts of the heart.
But for me the major question is how is it achieved and how it is not achieved in other organisms? Naturally, for COPD and its co-morbidities "internal injuries" regarding the lung and the heart are of primary interest. To me it is not clear whether the regenerative potential regarding these organs has much to do with the presence or absence of protection by the parents among different organims, and your argument of lack of usefulness of partially regrown organs does not seem to apply. What should be the problem with a gradual regrowing of a damaged lung? As an additional aspect, I think, one has to consider life expectancy and in particular age which interferes with regenerative capacities.
Based on these considerations I am not so much interested in explaining the presence or absence of regeneration as an adaptation but in understanding which genomic changes in the course of evolution (plus potentially epigenetic factors) have led to lack of capabilities. Insight into this could guide novel regenerative therapies aiming at reactivation of deactivated pathways. The idea is that e.g. genetic moduli for alveolar regeneration are more or less âaccessibleâ even in adult mice but not in adult humans. Could it be simply a result of differences in life expectancy and/or age, as small children probably can regrow alveoli, to a limited extent?
A different question is, why - from the point of view of adaptation - humans showing a much larger life expectancy than mice cannot regenerate parts of the lung that e.g. might have been damaged by smoke within caves, in the course of infections etc. We know from studies including those of ancient samples that under "natural conditions" humans can acquire degenerative disorders even in relatively young age. Is the (partial) lack of regeneration a price necessarily to be paid for the complex genetic and epigenetic pathways of human development? Can we re-open morphogenetic moduli without significant risk, particularly after learning from different animals? So itâs more a comparative approach to evolutionary diversity.
Again thank you for your response.
callahanpb · 9 April 2015
RAJ · 9 April 2015
@callahanpb
I agree, it would be at least as important as for COPD which is, however, already among the leading causes of death worldwide.
There is, of course, the newt but surprisingly very very few data (as for the lung), see Scadding SR, Liversage RA. Studies on the response of the adult newt kidney to partial nephrectomy. Am J Anat 1974 Jul;140(3):349-67.
There are rats and mice (which can also regenerate the liver much better than humans can), see e.g. Yang HC, Liu SJ, Fogo AB. Kidney regeneration in mammals. Nephron Exp Nephrol 2014;126(2):50.
And, who would not expect this, the zebrafish, see e.g. Davidson AJ. Kidney regeneration in fish. Nephron Exp Nephrol 2014;126(2):45.
There are also people working on supportive drugs (which can also have an effect in rodents regarding lung regeneration), see e.g. Gagliardini E, Benigni A. Drugs to foster kidney regeneration in experimental animals and humans. Nephron Exp Nephrol 2014;126(2):91.
But there is also the line of bioengineering via scaffolding etc which, in my opinion, is better suited for the kidney than for the lung, see Zambon JP, Magalhaes RS, Ko I, Ross CL, Orlando G, Peloso A, Atala A, Yoo JJ. Kidney regeneration: Where we are and future perspectives. World J Nephrol 2014 Aug 6;3(3):24-30.
I hope that is informative for you. I do not know of researchers following the approach which I have sketched for the lung.
Kind regards
ksplawn · 9 April 2015
I've heard that cancers can become more aggressive over the course of a patient's treatment, or return very aggressively years after remission, because the cancer cells that respond sensitively to the treatment are killed off while any malignant cells that have some sort of resistance remain behind to reproduce without competition. This triggers a round of evolution in the populations of cancer cells that promotes takeover by more aggressive and resistant strains that can fill in the niche left by more benign and sensitive ones. It was analogized to agricultural pests vs. pesticides and how we can inadvertently promote the spread of more resistant pests, except this process would play out within a single patient (for obvious reasons).
RAJ · 9 April 2015
@ksplawn
Yes, this is a major problem. One of the modern strategies, informed by systems biology, is to design drug therapies that hit multiple pathways at once or in succession so that as many âways of escapeâ as possible are no more accessible for the tumour cells.
harold · 9 April 2015
harold · 9 April 2015
callahanpb · 9 April 2015
Robert Byers · 9 April 2015
RAJ · 10 April 2015
@callahanpb
There are several strategies. One of them is to use cells from the individual patient to generate a kidney or parts of it externally using scaffolds plus bioreactor and then to implant the tissue or organ. Kidney implanatation is certainly more feasible than implantation of the lung therefore this makes sense for the kidney. The candidates are patients with severe disease.
This might change with the approach of promoting âin situâ regeneration. Who should be the primary target for this? Possibly not patients with advanced disease and largely destructed organs but patients with mild to moderate however progressive disease. These patients could offer enough residual morphological and functional structure to support in situ regeneration. This aim is much more modest that de novo generation. However, it could be difficult to convince others, particularly health care providers, that this is a reasonable decision for treatment. Certainly we would need large long-term studies.
To illustrate this point: There is a genetic disorder, alpha-1-antitrypsin deficiency, which is associated with low levels of an important anti-protease. This can promote the development of severe lung emphysema. The substitution therapy is extremely expensive and its effectiveness often questioned but we do not have a plausible alternative. If the therapy is paid by insurances at all, then only in patients with advanced disease. In my opinion, much better candidates would be patients with beginning lung disorder in whom you might have a greater chance to inhibit or slow down the fatal disease process. In this case itâs about destruction but the argument for regeneration would be similar.
James Downard · 10 April 2015
This fine post (and the comments thread attached) is entering my #TIP www.tortucan.wordpress.com/ counter-creationism resource (read Nick Matke's post here on Pandas on what #TIP is about and how to support it http://pandasthumb.org/archives/2015/03/troubles-in-par.html#more), part of the ongoing contrast between the vacuous nothing that is YEC/ID on this front and the detailed evidence focused evolutionary science.
Naturally antievolutionists rationalize and even attempt to coopt snippets of the data set (as YECer Tomkins does for AiG) but there is only so far one can push water uphill without it sloshing back down again. Byers comments are most illustrative of the rationalizing mind at play, but the work will still be done by the scientific community, and as in so many other areas of science (think paleontology or developmental biology) increasingly evolution will illuminate and guide that study.
Steve Schaffner · 10 April 2015
harold · 11 April 2015
MFMartins · 19 April 2015
I find DR. Joe Alcock's idea to be fascinating, the idea that modern medicine could be interfering with the natural progress of evolution. When we think of it a difference in ones genome to the norm is basically a mutation and favourable mutations bring about evolution over time so cancelling out or fixing the change could be a serious problem. This could just be another case of man ending mankind...
Does anyone know of any other research on this matter, I would like to read more about it.
(u15202390)
harold · 20 April 2015
John · 20 April 2015
I just stumbled upon this now. Emily, thanks for writing a great blog post and am looking forward to reading more from you in the future. I am reminded how a noted British epidemiologist showed a picture of a young Charles Darwin after the HMS Beagle voyage, declared that he was the founder of our science, and no one in the room except for yours truly could raise his hand when he asked who that fellow was. (This was at a faculty lecture he gave when he was a visiting professor at an epidemiology department I worked for years ago .) The reason why I am saying this is that more people should realize that epidemiology, as well as evolutionary medicine, is based on Darwin's work on Natural Selection.
harold · 20 April 2015
John · 20 April 2015
TomS · 20 April 2015
Perhaps there are people who do not think that explaining the medical (and agricultural, ecological, geological, etc.) world is useful.
harold · 21 April 2015
Tomato Addict · 27 April 2015
If anyone was not already aware of this:
J Mol Med (Berl). 2012 May;90(5):481-94. Epub 2012 Apr 27.
Nothing in medicine makes sense, except in the light of evolution.
Varki
http://www.ncbi.nlm.nih.gov/pubmed/22538272
John · 29 April 2015