Malarial mosquitoes are evolving into new species, say researchers

Oct 21, 2010
An Aedes aegypti mosquito feeding in Dar es Salaam, Tanzania. Image credit: Muhammad Mahdi Karim, GNU FDL.

Two strains of the type of mosquito responsible for the majority of malaria transmission in Africa have evolved such substantial genetic differences that they are becoming different species, according to researchers behind two new studies published today in the journal Science.

Over 200 million people globally are infected with malaria, according to the World Health Organisation, and the majority of these people are in Africa. Malaria kills one child every 30 seconds.

Today's international research effort, co-led by scientists from Imperial College London, looks at two strains of the Anopheles gambiae mosquito, the type of mosquito primarily responsible for transmitting malaria in sub-Saharan Africa. These strains, known as M and S, are physically identical. However, the new research shows that their genetic differences are such that they appear to be becoming different species, so efforts to control mosquito populations may be effective against one strain of mosquito but not the other.

The scientists argue that when researchers are developing new ways of controlling malarial mosquitoes, for example by creating new or trying to interfere with their ability to reproduce, they need to make sure that they are effective in both strains.

The authors also suggest that mosquitoes are evolving more quickly than previously thought, meaning that researchers need to continue to monitor the of different strains of mosquitoes very closely, in order to watch for changes that might enable the mosquitoes to evade control measures in the future.

Professor George Christophides, one of the lead researchers behind today's work from the Division of Cell and Molecular Biology at Imperial College London, said: "Malaria is a deadly disease that affects millions of people across the world and amongst children in Africa, it causes one in every five deaths. We know that the best way to reduce the number of people who contract malaria is to control the mosquitoes that carry the disease. Our studies help us to understand the makeup of the mosquitoes that transmit malaria, so that we can find new ways of preventing them from infecting people."

Dr Mara Lawniczak, another lead researcher from the Division of Cell and Molecular Biology at Imperial College London, added: "From our new studies, we can see that mosquitoes are evolving more quickly than we thought and that unfortunately, strategies that might work against one strain of mosquito might not be effective against another. It's important to identify and monitor these hidden genetic changes in mosquitoes if we are to succeed in bringing malaria under control by targeting mosquitoes."

The researchers reached their conclusions after carrying out the most detailed analysis so far of the genomes of the M and S strains of Anopheles gambiae mosquito, over two studies. The first study, which sequenced the genomes of both strains, revealed that M and S are genetically very different and that these are scattered around the entire genome. Previous studies had only detected a few 'hot spots' of divergence between the genomes of the two strains. The work suggested that many of the genetic regions that differ between the M and S genomes are likely to affect mosquito development, feeding behaviour, and reproduction.

In the second study, the researchers looked at many individual mosquitoes from the M and S strains, as well as a strain called Bamako, and compared 400,000 different points in their genomes where genetic variations had been identified, to analyse how these mosquitoes are evolving. This showed that the strains appear to be evolving differently, probably in response to factors in their specific environments - for example, different larval habitats or different pathogens and predators. This study was the first to carry out such detailed genetic analysis of an invertebrate, using a high density genotyping array.

As a next step in their research, the Imperial researchers are now carrying out genome-wide association studies of , using the specially designed genotyping chip that they designed for their second study, to explore which variations in mosquito genes affect their propensity to become infected with malaria and other pathogens.

Explore further: Warning coloration paved the way for louder, more complex calls in certain species of poisonous frogs

More information: --DE Neafsey et al. Complex gene-flow boundaries among vector mosquito populations. Science. DOI: 10.1126/science.1193036 (2010).
--MKN Lawniczak et al. Widespread divergence between incipient Anopheles gambiae species revealed by whole genome sequences. Science. DOI: 10.1126/science.1195755 (2010).

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Birthmark
4.8 / 5 (5) Oct 21, 2010
Evolution in the making, what now creationists? XD
Shootist
2 / 5 (3) Oct 21, 2010
Oh, they will call it 'micro' evolution and look the other way. What the difference is between 'micro' and, what they refer to as, 'macro' evolution, I can only guess.

But I really posted to again call for the return of DDT and pouring oil on swamp water to kill these bugs. Dengue Fever, also mosquito carried) has returned to Florida after an 80 year absence.

People are dying in the name of environmental extremism and it has to stop.
Vendicar_Decarian
3.7 / 5 (3) Oct 21, 2010
"But I really posted to again call for the return of DDT and pouring oil on swamp water to kill these bugs." - Conservatard

Those who listen to the lying Conservative media are doomed to remain ignorant.

The face is that DDT has never been globally banned for use against malaria, and in fact has been in continual use against malaria world wide since the 1972 ban of that chemical in the U.S.

In face in 2005 the World Health Organization called for a moderate increase in the use of DDT in countries where Malaria is a problem.

I have never encountered a Republican who wasn't a congenital and perpetual liar.

Tesla444
1 / 5 (6) Oct 22, 2010
So far this will be the ONLY example of one species evolving into another, Wow! If this is true, that means there should be millions of trial & error attempts as a new species evolves - for every species. Oh, right there are NO transitional examples of an evolving species, so this will be the first (yes, I know about the few supposed examples that have been claimed but not proven). Clearly, this is absolute proof that evolution is not the crock of wishful thinking we all knew that it was. Sorry, I believe in Scientific Method and it has never been applied to the Theory of Evolution, maybe its time to start!
Donutz
5 / 5 (5) Oct 22, 2010
Oh, right there are NO transitional examples of an evolving species


Exactly what would you consider a transitional species? The trouble with this objection is that, since transitional species don't have a flashing neon sign above them that says "transitional species here! come and see the transitional species!", creationists simply deny any examples. I don't know what the current creationist objection to Eohippus et al is, but I imagine it's something along the lines of "you can't prove it".

I think a simple working definition of a transitional species would be any species that is clearly moving from one environment or niche to another, and and somewhat adapted for both. On that basis, penguins, sea lions, and sea otters are pretty good examples. Of course, since I don't have photographs of them evolving, the creationists will still object "you can't prove it".

Skeptic_Heretic
4.4 / 5 (7) Oct 22, 2010
So far this will be the ONLY example of one species evolving into another, Wow!
Actually this would be one of 680 million recorded transitional species markers.
If this is true, that means there should be millions of trial & error attempts as a new species evolves
Yeah, they're called the dead, or if you prefer "Ancestor".
- for every species.
We all die
Oh, right there are NO transitional examples of an evolving species,
Because all species are constantly evolving, even us.
so this will be the first (yes, I know about the few supposed examples that have been claimed but not proven).
There's no proving evolution any longer, it is proved. With every generation there is change.
Sorry, I believe in Scientific Method and it has never been applied to the Theory of Evolution,
You're fantastically ignorant.
Donutz
5 / 5 (6) Oct 22, 2010
Sorry, I believe in Scientific Method


Sure you do. And you also believe in creationism, er, I mean "Intelligent Design". Because *that* stands up to scientific scrutiny. LOL.

Tesla444
1 / 5 (4) Oct 22, 2010
Donutz, actually I said Scientific Method, not Creationism. Perhaps your English needs a little refresher course. Look it up you will find it quite enlightening. Just because you hate Creationists doesn't mean that I am one or that you are right. You are the perfect example of an Evolutionist who ignores facts because it doesn't suit your belief system. Scientific Method is applied rigorously to all other fields of Science, what is wrong with applying it to Evolution. Don't worry your not the only one. It seems that Skeptic_Heretic is a bit misinformed as well, but he is great at cute, but pointless comments.
Skeptic_Heretic
4.2 / 5 (5) Oct 22, 2010
Scientific Method is applied rigorously to all other fields of Science, what is wrong with applying it to Evolution. Don't worry your not the only one. It seems that Skeptic_Heretic is a bit misinformed as well, but he is great at cute, but pointless comments.
Cite your contrary evidence that disputes the FACT of evolution.
trekgeek1
5 / 5 (3) Oct 22, 2010
@Tesla444

The evidence points to evolution being at very least, the BEST explanation of life on earth. Do you believe creationism is a better explanation? If so, how is that supported by evidence? If you are not a creationist, then in your opinion, what is the best explanation for life on earth? We need to have some theories on how all this happens, so choose one. Personally I recommend you choose evolution since it has been heavily supported by the scientific method you so dearly support.
Tesla444
1 / 5 (2) Oct 23, 2010
I agree with trekgeek1 that evolution may be the best explanation so far, but Evolutionists have a closed mind to any other possibilities. In the field of Paleontology up until recently it was thought that most dinosaurs were cold blooded, until a few scientists actually applied Scientific Method to their research & demonstrated that they were not-now accepted by most scientists-after much resistance over many years. We discuss & dispute science all the time in EVERY OTHER FIELD, but NOT in Evolution. I'm only trying to get us to think outside the box for a change, maybe develop a new theory based on ALL the facts. Evolution makes certain assumptions about how life evolved & many seem reasonable, but there are still too many huge gaps that don't fit. Darwin was brilliant & developed his theory based on his limited observations, but it was incomplete (as he even noted). 150 years later we can't improve on it?? This doesn't make sense. Let's at least try! I hope this helps to clarify.
Skeptic_Heretic
3 / 5 (2) Oct 23, 2010
This doesn't make sense. Let's at least try! I hope this helps to clarify.
Then engage the method and cite your contrary observations.
Tesla444
1 / 5 (4) Oct 23, 2010
We, who believe in Scientific Method must be willing to re-think our concepts & even 'beliefs' from time to time. Evolutionists have long resisted such heresy, which is why the field has stagnated for 150 years. The issue of Species is a prime example: when Darwin's definition interfered with some recent factual findings, Evolutionists in the early 50's simply changed the definition of Species. The trial & error process described by Darwin should produce Transitional Species, yet we don't see it in the fossil record. CONSIDER THIS: "In order that the case against evolution be heard, scientists who question Evolution decided to hold their own conference. It should be emphasized that these scientists are not creationists & would be offended to be considered as such. The arguments against evolution are rarely heard because academic institutions such as PAS prefer to restrict their presentations to data that, in their view, support the theory." http://dinosaurc1...nces.htm
Skeptic_Heretic
3.7 / 5 (3) Oct 23, 2010
Can you define the word species for us?
Tesla444
1 / 5 (4) Oct 23, 2010
Another conundrum: If you recognize that the whole natural world operates according to the “Second Law of Thermodynamics” which states that for isolated systems entropy, which is a measure of probability, will always increase, you must question the basic premise of Evolution, as currently stated. Entropy determines the direction in which all processes in nature proceed: from less probable distributions to more probable distributions, from ordered structures to disordered ones & NEVER vice-versa.

Evolution relies on the opposite occurring naturally, randomly - that a series of genetic mutations, over long periods of time will produce a higher level life-form by mutating to a new species ranging from an ameoba to a Human. This flies in the face of common sense if, as a scientist, you accept the 2nd Law of Thermodynamics. The implication is that in order for Entropy to be countered, there must be some external influence on these life forms. What does this mean? The birth of new Theory??
Tesla444
1 / 5 (3) Oct 23, 2010
A conundrum: If you recognize that the whole natural world operates according to the “Second Law of Thermodynamics” which states that for isolated systems entropy, which is a measure of probability, will always increase, you must question the basic premise of Evolution, as currently stated. Entropy determines the direction in which all processes in nature proceed: from less probable distributions to more probable distributions, from ordered structures to disordered ones, NEVER vice-versa. Evolution relies on the opposite occurring naturally, randomly-that a series of genetic mutations, over long periods of time will produce a higher level life-form by mutating to a new species, ranging from an amoeba to a Human. This flies in the face of common sense if, as a scientist, you accept the 2nd Law of Thermodynamics. The implication seems to be that in order for Entropy to be countered, there must be some external influence on these life forms. What does this mean? The birth of new Theory??
Tesla444
1 / 5 (2) Oct 23, 2010
Sorry for the repeat I got redirected to some strange page and then couldn't delete the second version of my last comment.
KBK
1 / 5 (1) Oct 24, 2010
mms (Jim Humble) saves lives and kills malaria infection in a single dose, and does it for 5 cents. And it is made from a common chemical.

Which is why, when we use it (extensively) to kill bacteria with no side effects...why it is being outlawed for human use.

Gates and the pharmaceuticals were never about saving lives, but controlling and wiping out populations while making money.

Doubt me?

Do the research, dig into it. Prove the statement wrong to your satisfaction.

It can't be done.
Skeptic_Heretic
3 / 5 (2) Oct 24, 2010
A conundrum: If you recognize that the whole natural world operates according to the Second Law of Thermodynamics which states that for isolated systems entropy, which is a measure of probability, will always increase, you must question the basic premise of Evolution, as currently stated.
The Earth is not a closed system.
KitchenDancer
5 / 5 (3) Oct 25, 2010
Evolution relies on the opposite occurring naturally, randomly-that a series of genetic mutations, over long periods of time will produce a higher level life-form by mutating to a new species, ranging from an amoeba to a Human. This flies in the face of common sense if, as a scientist, you accept the 2nd Law of Thermodynamics.

Actually, though it is a little counter-intuitive, the random mutation component of the theory of evolution does lead to a more disorder, entropic state. These mutations, new gene interactions, etc are chaotic - not goal oriented. For the prevalence of a mutation to achieve more than a negligible frequency, there does need to be a selective force (and there are many!) or no substantial detriment to the mutant organism.
Birthmark
5 / 5 (1) Oct 31, 2010
I can't believe we're in the 21st century and still arguing over the reality of evolution's existence. Not only do we have substantial micro-evolution, we now have a fine example of macro-evolution. Is religion clouding people's minds or ignorance? I think they go hand in hand actually.
Tesla444
1 / 5 (1) Oct 31, 2010
Skeptic: Perhaps, but an example of the operation of entropy is genetic degeneration of a biological species due to negative mutations: The opposite—a succession of small genetic variations lead by natural selection to the construction of a completely new organ—is an excluded process of decreasing entropy. An objection to the above premise is that the constraints of thermodynamics are not valid for biological structures because they exist in open systems (your point). “Open” means that matter & especially energy can be exchanged with the surroundings. The reason why the evolution of biological organs does not belong to such processes is that these are the physical ways in which a pre-existing order is transferred from one level to another. No really new order or information is generated in any of these open-systems. It is always an energetic necessity that the pre-programmed ordered structures appear. Thus, open systems do not create order. They only make hidden order visible.
Tesla444
1 / 5 (1) Oct 31, 2010
More: "On the other hand, the bodies of living creatures represent new information. It is not pre-contained in the molecular structure of constituent chemical elements nor is there a machine which is programmed to produce it. There is no physical arrangement which contains the information which is necessary to build up life from non-life or complex creatures from simpler creatures. It is excluded by the second law of thermodynamics because it does not belong to those pre-programmed structures which open systems can create! It follows that the evolution of man from molecules is precluded by the fundamental laws of nature." *This & previous is quoted, in part, from a paper by Dr. Thomas Seiler, Ph.D., University of Munich. --Birthmark - We are not having a religious discussion here - please stop using it as an excuse. I'd just like to see supposed scientists stop acting as if Evolution is a belief system and thus not subject to new ideas, discussions or scientific method to support it.