My answer have dissapeared. Maybe the problem of editing, who knows! 

Dear @Hossein, many of us are both scientists and believers. How to accept the fact of creation science vs evolutionary science!? " ...the U.S. Supreme Court in effect decided in 1987 that the Biblically based "creation science" is not a science and cannot be taught as such in public schools as an alternative or in addition to the mainstream evolutionary theory of the biological sciences. However, religious creation stories and the idea of "intelligent design" can be taught in philosophy, religion, or history courses. Religion and Science provide different approaches to knowledge. It is important to understand both..."

Good reading follows!

http://anthro.palomar.edu/evolve/evolve_3.htm

http://anthro.palomar.edu/synthetic/default.htm

My answer have dissapeared. Maybe the problem of editing, who knows! 

Dear @Hossein, many of us are both scientists and believers. How to accept the fact of creation science vs evolutionary science!? " ...the U.S. Supreme Court in effect decided in 1987 that the Biblically based "creation science" is not a science and cannot be taught as such in public schools as an alternative or in addition to the mainstream evolutionary theory of the biological sciences. However, religious creation stories and the idea of "intelligent design" can be taught in philosophy, religion, or history courses. Religion and Science provide different approaches to knowledge. It is important to understand both..."

Good reading follows!

http://anthro.palomar.edu/evolve/evolve_3.htm

http://anthro.palomar.edu/synthetic/default.htm

It is known that scientific theories "comes and go". This e.g does not happen with mathematics, where the knowledge is accumulative and very little neatness. Today the Theory of Evolution has a strong exegetical power and it is like Newton's physics for Biological sciences. Until there will be an alternative falsified "evolution" we have to accept it.  

Nice answers , thanks.

if i may; no offense of course; i want to say that i'm not convinced by mr @Drossos's answer; it's not fair to throw away a great scientific finding so easily just because science isn't built upon a formal system of atomic axioms and rules like math(actually if i remember well math had its own share of inconsistencies too); i mean it's maybe a good thing for science as we know today that it comes with the assumption that over time some facts may not be facts anymore; but my point is, years ago scientists postulated the existence of genes as heritable characteristics of living creatures encoded in their DNA, yet it took 50 years or so to gather enough evidence to turn it into a universally accepted fact that the gene exist and they bear the life's blueprints; so i think accepting scientific findings as reality just based on really loose assumption that "i accept it but when given enough time our knowledge grows there is a great chance that it's not valid anymore, so be it!" is a very weak premise; i think most people may have two problems related to accepting Evolution:

1 - It seems because Evolution is so simple, the simplicity made it really really hard for people to grasp the idea;

2 - Because Evolution itself try to explain how we come to have obtained cognition and thinking over the generations, it's hard to think about Evolution, as it influenced how we think about the world and all in it in the first place!;

Dear Hassan,

It is well known that scientific theories are not absolute truths. For example Newton Mechanics does not hold in the quantum level. So theories may become better and better, but there are examples that some scientific theory was completely falsified. 

I just state something that all scientists accept! I really do not understand you objections. Maybe I misinterpreted you. 

dear mr Drossos;

let's assume a scientific theory is real if at least one of four(weaker to stronger from up to down)below holds:

my objection is based on the idea i get from your first post for this question, that it seems you based your argument on the number 2 about reality of scientific theories; what if we presume the number 3 holds?, i mean can we assume Evolution as exactly true or at least a good approximation of reality? not just another cute theory, as in the number 3 all scientific theories are not equal in credibility.

Dear Hassan,

A scientific law describes the behavior of something that occurs. It is often described in mathematical relationships. For example the general law of gravitation describes the force between objects of various masses at various distances

A scientific theory, however, attempts to describe why something works. There are several theories of gravity, which attempt to explain why it occurs as it does.

Both Scientific Theories and Laws are based upon observation and experimentation. They can be disproved or modified to accommodate new discoveries, and must make predictions about future experiments and observations.

Here is a picture of mathematical model:

Science is knowledge the rest is belief. Any paleontologist can see how over at least 600 millions years life & organisms have evolved with some cataclysmic events during the course. There is no need of a theory for that, its just plain observation. The impact of Shoemaker-levy on Jupiter reminds us that life on earth must strive sometimes hard to survive on the very long term (e.g. KT impact), though Jupiter is more often hit than us due to its huge mass. I've enjoyed writing a paper on that recently:

https://www.researchgate.net/publication/267330984_Revisiting_the_Collision_of_D1993_F2_%28ShoemakerLevy%29_with_Jupiter_20_years_later_a_Planisphere_is_worth_a_thousand_words?ev=prf_pub

Article Revisiting the Collision of D/1993 F2 (Shoemaker–Levy) with ...