Pollution is a strong alterer in evolution, and man is largely responsible for this. Pesticides and anti-metabolites used carelessly by man is causing extiction of many birds (vultures, sparrows, etc) and other microbial species. Transgenics spread by man are changing the natural course of evolution of life on earth.

The classic example is the peppered moth. Light color moths become scarce. Dark moths survive because they are not seen and eaten by birds during the Industrial revolution. This natural selection is caused by burning of fossil fuel. What more in countries that want to use energy from nuclear plants? Disasters cause deaths, and radioactive pollution. What happened to the generation of Japanese children in Nagasaki after 1945? Do we feel sorry for them?

Pollution is due to the lot of industries all over the world without taking care of agriculture

Environmental pollutants (especially the mutagens) may induce stress & genetic mutation in living creatures. Off course, not all these mutations are adaptive or get carried over generations (inherited) by a population. Nevertheless, there are evidences where pollutants (e.g. biomedical) have induced adaptive changes (evolutionary) in populations (e.g. microbes). These are just some examples:

1. http://www.pnas.org/content/99/25/15904.full.pdf+html

2. http://www.nature.com/news/2008/080113/full/news.2008.439.html

Cheers!

Dear Dr. Gamal Badawy

What you have to say about many new and different types of diseases caused by microorganisms which came into existence in past centuries??

Regards,

Nitish

Dear Miranda,

Really a "classic example" :-)

Regards,

Nitish

Dear Dr. Gamal

Can't we say that it is evolution in micro organism so that the diseases which was unknown to us previously has come into existence latter?

Regards,

Nitish

Classic example indeed, Yeoh!

One must understand that evolution is all about inheriting changes over generations guided by natural selection.

And Dr. Gamal, i guess you need to refresh your understanding about the term and the processes of evolution if you think that the above cited classical example of Peppered Moth has no link with the subject under discussion.

The most important driver of evolution is natural selection. However, Man, with his science has been successful to some extent, to circumvent this natural force. How long will he be able to do that is a big question. Time has the answer in store for our descendants.

The peppered moth is a good example indeed.

Let me answer it some other way.

Lets consider 'evolution' as a giant wheeled chariot. (one can say juggernaut) in the light of the theory of natural selection. Pollution is one of the wheels. Species survived from crushing can ride on it to proceed further.

Dear Darashing,

Interesting answer and different perspective.

Regards,

Nitish

Dear Gamal,

What is the definition of evolution according to you? and how others definition it is contradicting yours ?

Regards,

Nitish

Dear Michel

Thanks for your valuable contribution and insight.

Regards,

Nitish

Dear Gamal, please check out the following link as a simple answer for your question:

Peppered Moths as an Example of Natural Selection:

http://www.windows2universe.org/cool_stuff/tour_evolution_8.html

Regards

dear all,

it is clear from the discussion so far that we all agree that pollution represents environmental challenges, that can affect the fitness of organisms. This implies that pollution represents selective pressures, which may lead to adaptation of these organisms through processes of mutation, natural selection and genetic drift. This has been called micro evolution, and indeed a good example in the context of pollution as environmental challenge is that of the peppered moth, and possibly also color polymorphism in the 2-spot ladybird beetle. With this we all seem to agree, including Gamal Badawy, and it may actually answer Nitish's original question. Gamal, however,does not consider this process evolution, but uses a narrower definition that bears on macro evolution. Obviously, Gamal believes in creation of major lineages, followed by micro evolution within those lineages. Although Gamal has the fullest right to believe so, and I respect this belief, it takes the discussion out of the realm of science, and changes the original question (going back to science) into: could pollution, through processes of micro evolution, lead to genetic isolation between lineages, which may eventually lead to reproductive incompatibility, and hence speciation according to the biological species concept. In the peppered moth, for example, this could evolve if there were assortative mating within the color forms. I argue that this is equally plausible for selective pressures associated with pollution as for, say, the use of a new, introduced host plant by a phytophagous insect (e.g. the apple maggot fly, by way of a classic example). Moreover, pollution could also have direct effects on the genome (mutagenesis, think of Chernobyl) which might also influence evolution (micro- as well as macro). I hope this has has clarified our different interpretations of the original question, and in any case I have hereby given my view.

Dear Peter

Thanks for joining the discussion.

Nice point of view and excellent description.

Regards,

Nitish

thanks Nitish! There is another thing that may be added: one of the characteristics of some forms of man-induced pollution is the intensity of the environmental challenge, and the speed with which the challenge arises, as well as the sometimes large geographic scale at which it occurs. This may lead to mortality, infertility etc., which then might lead to extinction rather than adaptation and thus evolution. A good example here is the application of insecticides (which at least from the perspective of the target species may be considered pollution): if a dose of application does not kill all target individuals, the stage is set for evolution (micro ;-) of resistance. with a high, lethal dose, resistance is unlikely to develop, unless there is migration between populations that are, and are not treated with insecticides. Perhaps you were also alluding to this in your original question?

Dear Peter,

I liked your example of insecticides and Yes! I was also trying to allude the same in my question.

One of my personal observation is on mosquitoes. Initially we used to keep them away from our house by using mosquito coils (of different forms solid or liquid). But now they have became resistant and adjusted to all these and evolved in such a way that using these do not affect them much.

Regards,

Nitish

Dear Michel,

Nice stuff! I have also been thinking more about this, and remembered the book of Patrik Nosil "Ecological speciation" (Oxford University Press, 2012). Although I do not think there are specific examples in there about response to pollution, the link between micro- and macro evolution is nicely illustrated, and these examples might help our thinking about effects of pollution (as an environmental challenge) on evolution as well.

Best regards,

Peter

There is clear evidence that pollution drives micro-evolutionary processes in several species. When micro-evolution due to pollution occurs ,populations inhabiting environments that become polluted may persist, as a consequence of the genetic adaptation to the toxic substance. Micro-evolution due to pollution may alter physiological and genetic properties associated to the affected populations

In my opinion, when changes occur in a system by adding factors which work against some organisms, then this opens up the possibility to those and to other organisms to compete in filling up that part of the system via adaptation and change. Again, I have no experience about this and only imagine from my perspective, if a population is reduced or eliminated, it's place is available for others to occupy. These others can be a) either adapted individuals from the initial populations, b) can be existing exterior species which are fine with the changed system and were previously excluded by the original population (competition, food chain inferiority, etc.), or c) by adapted individuals of the other external species which become tolerant to the factors that changed the initial system.

If we refer to a) then changes which allow adaptation to the new system have the potential to isolate the species from the un-adapted ones, such that in time, divergence may occur to some degree.

In the case of b), I think that no evolution appears directly, but might force changes in the populations which were unaffected by the changing factors themselves, yet suffer pressure from the external species which just moved in.

Thinking about c), my opinion is that it's sort of a combination of a) and b), meaning that you may have direct divergence of the adapting entering species, as well as pressure exerted by these on the originally unaffected existing species.

Also, I believe that even without dramatic initial impact, adding stuff (like pollutants) to the system triggers response from that system which can dictate the course of changes, some of which may be natural anyway but some not. Let's not forget that no system remains unchanged over time, even since before human existence, such that it's sometimes difficult to quantify the exact degree of the anthropic factors.

It's not clear for me how it's considered and labeled when evolution towards certain characteristics occurs anyway and it's only accelerated, slowed down, tilted towards some fine details or towards others by the human activity. Also, I'm unaware of how you consider changes in species unaffected by human activity, but affected by pressure from species who's evolution was influenced by humans.

Is it considered natural evolution, human influenced evolution, human triggered change, or something else?

In my mind, complete and direct human attributed evolution is selective breeding, modern genetic manipulation and older genetic manipulation (like selective inter-breeding in plants and animals). Other changes are simply assisted, accelerated or slowed down by anthropic factors; then of course is (was) the isolated evolution completely outside of human influence at any level.

In hope that I learn something about the subject,

Best regards!

Dear Andrei Neacsu sir,

If you will go through previous discussions then it will probability clear some of your doubts.

Also you emphasized more on "population" but my discussion is related to "pollution".

Regards,

Nitish

Pollution comes in all shapes and sizes and can have very direct effects on evolution. For example, pollution can interrupt chemical mating cues which have lead to hydridisation in some fish species. Light pollution causes changes in mating behaviour in some amphibian species and noise pollution affects species assemblages of birds due to the disruption of song communication. Obviously, there are more direct effects that pollution has, many of which I suspect have been mentioned, but 'pollution' in it's broadest sense has far reaching effects beyond those that are commonly thought of.

Definitely an interesting question with many answers!

Pollution is a very broad term. No doubt species adapt to new environment for survival. This adaptation is either temporary or permanent. Temporary means if the environmental changes are short term then tools of adaptation are also temporary because in general species try to preserve the original set up . As far as my knowledge goes pollution is intra, inter and external. Intra means inside the body, inter means in between species or related animals and external means due to external factors like temperature, sunlight, earth's magnetic field etc. This is a very complex reaction. Those who solve this complexity can survive otherwise fail then cripple or become extinct.. The pollution is capable of making changes in the genetic set up of species. Take an example of mosquitoes, earlier DDT was a powerful weapon to control but soon mosquitoes changed the set up and now it is a food for them ! DDT is a synthetic external factor !

Invasion of P. vivax in the body is a type of pollution caused by many factors. In general it is seen that in the countries where malaria is common , the Hb percentage in the blood is moderate causing moderate anemia. Naturally iron depletion forces the parasite to leave the place. This is a type of adaptation for survival.

Thanks Gemma, Arun and Michel for participating in the discussion and sharing the valuable information.

Regards,

Nitish

Dear Gemma,

Your examples are excellent.

Thanks for bringing those effect and forms of pollution in our consideration.

Regards,

Nitish

Dear Arun,

The example of mosquito is my personal observation also and I have also discussed about it in one of my above reply.

Mosquitoes are also one of the reason of my inspiration in asking this question. :-)

And information about Hb and Anemia is new to me.

Thanks for sharing this information with us.

Regards,

Nitish

Dear Michel : Thanks for your reply. I always think that moderate anemia in the malaria infested area is a sort of evolutionary medicine which is developed by the body . It is a natural development. One should not look in to such interactions merely from the host-parasite relationship way.

Arun Panat

Dear Nitish : I do not appreciate thanks as a formality. Please have a close interaction and friendship.

Arun Panat

Dear Michel : May I request you to mail a copy of your thesis "community composition in high altitude andean streams and work of Raul Loayza-Muro " ?

Thanks,

Arun Panat

Dear All : Yes I agree that in many cases pollution impact on the species is negative but it may not be always true. There may be some cases which may be showing positive impact and more fit species. Positive impact may also be taken in to consideration even though its percentage of occurrence is limited. Natural evolution of a tool by the host body to combat pollution ( As I call P. vivax infection as a pollution) with a very little or no damage to the host body is a sort of positive phenomenon.

Arun Panat

I completely agree with you Nitish. Increasing pollution caused many negative changes in biological and genetic characteristics of species on earth.

Thanks Mahfuz.

Regards,

Nitish

Dear All,

I agree with Mahfuz Judeh.

Best regards,

Ahmad

Thanks Ahmad.

Regards,

Nitish

I agree with Mahfuz Judeh that increasing pollution has produced many negative changes in biological and genetic characteristics but as yet no one thinks of some positive sides too. Pollution as we call then biological and genetic changes in the species and then evolution of more fit species is the journey. Today we feel that these are negative changes but in future they are essential changes. Emergence of new species after say 1000 or 10,000 or 100000 years is a continuous process. It will go on and on ! In fact today's species is a result of many such interactions which occurred 10000, 100000 or 1000000 years ago !

Yes , Michel : you are perfectly right . Yes small organisms living symbiotic life in the host may get affected first signaling the host to adapt for new changes. Certainly nutrient availability , changes in nutrients etc may be affecting positively.

I have found that people always think of negative effects and afraid of positive aspects ! May be a set up of opposition for new things ............. new species 1

Dear Michel : With a strong proof you can put up your views in the conference and to the journal which you will be contacting for its publication. Do not afraid of any criticism instead strong proof will nullify the criticism. Think when Gregor Mendel was telling about inheritance of factors ( Genes now) , its pattern , no body listened him at the beginning but later the world had to accept it. Many scientists like Schrodinger etc had to face criticism at the beginning. Later their theories were accepted . That led to the development of Quantum Mechanics further and now it is an essential part of Physics teaching. If you are correct then do not afraid !

Thanks Arun and Michel for pointing positive effects too! :)

And Michel, every new idea takes time to establish itself. Present your paper with full confidence. All the Best for your PhD paper. :)

Regards,

Nitish

There is natural "pollution" in certain niches, such as the high levels of thorium, uranium, and (now) man-made plutonium as "normal" background radiation in southern Utah and Nevada. This is not normal in other areas! In fact, you really don't want to be out in dust storm there! The plants and animals which live there have evolved and adapted to this back-ground radiation "pollution". I think the desert tortoise has some best DNA repair enzymes around and I'm surprised they are not studied further. We maybe doing our "own" selection in our large cities, where people who are better at: detoxifying pollution, liver repair, DNA repair, immunity (diseases in larger populations), and so forth are doing "even" at little bit better, if not a lot. Hence, humans may have already "evolved" to do better in a more "toxic" environment. Given the pollution in large cities; it might be fun to check Londoners to some American Indians, or Inuit Tribes on differences on a wide spectrum of genes that one would "think" might be effected from our pollution.

Michel, there are also plants that clean up high metals, and other special organisms. So I think you will have some strong arguments.

Dear Heidi,

Of-course, these are some of the strong arguments!

Thanks.

Regards,

Nitish

The history of the biosphere, its evolution, and pollution have been intertwined from day one. It was pollution with oxigen, a waste produced by bacteria and blue-green algae that finally led to their demise, or in some cases it appears to have been extinction, and to the raise of oxigen-consuming organisms, as we do not, plenty for physiological needs and industrial purposes. There was an interesting twist: Not until the Great Oxigenation Event was completed, and all oxigen trapped as iron oxides, that an oxigen-rich atmosphere began to develop and expand. The rest is history: Life's march toward complexity. Us?

Aldo,

I like your long-time view. It reminds us how we are only blip in Earth's history, and even less of a blip in stellular history. But being the blip, I hope we have enough genetic diversity (and smarts) to handle the forth coming challenges cause by our huge population. These challenges are from; pollution, our main "predators" (the virus and bacteria), and ourselves (war, resources, starvation). I think humans are already under very strong selection pressures and these pressure will only increase. People have to juggle reproduction, education, and obtaining recourses (money, land, etc.).

Heidi

Briefly, there are many factors that causes evolution such as (Natural selection, mutations, genetic drift, immigration,..). Pollution have a direct effects on many of those factors. It simply can induce mutations and can also act as stress for selection besides changing many environmental factors. So, the answer for your questions is "yes" , the Pollution have a great effects on evolution. ;)

Thanks Aldo and Ahmed for your views.

Regards,

Nitish

Interesting question. No one can deny the statement that pollution has bad effect on evolution. I think, growing population and unplanned urbanization are also forms of pollution which are usually ignored. I do agree with @Ahmed Mansour Alzohairy that there are many factors that causes evolution such as (Natural selection, mutations, genetic drift, immigration,..). Pollution have a direct effects on many of those factors.

Thanks Asmat for your nice point.

Growing population and unplanned urbanisation are really the forms of pollution which is ignored by everyone in modern era.

Regards,

Nitish

Related to this is the excellent work by several researchers recently on epigenetic inheritance. It is very disturbing to me that exposure to some environmental contaminants can alter the genome without changing DNA and these changes in gene expression can be passed on to successive generations.

@James,

Thanks for your views

We can see these effects in our surrounding in our daily life.

Regards,

Nitish