ScienceBlog

Supporting 21st Century Science GCSE

ScienceBlog

Scienceblog.org is our own portal for students and teachers. It brings all our latest articles, free images, newsfeeds, downloads, multimedia resources, and weblinks relevant for the study of  21st Century Science. This site is o­ne of  number of complementary websites we have developed for science education. All developed using wonderful Open Source software!

Search this site...


Past Articles

Older articles

Multimedia Resources

Webucate Media Gallery
   More Resources!

Our Websites

Webschool
Global Community
OpenSchool.org.uk
OpenSchool Support Zone
SciGallery Community
SciLinks.org.uk
Science Support Zone
Coolwebschool.org
Support Zone 1
Webucation.org

Great Hosting

Web hosting

Translate me!

   

Science Quotations

Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe? The usual approach of science of constructing a mathematical model cannot answer the questions of why there should be a universe for the model to describe. Why does the universe go to all the bother of existing?

-- Stephen William Hawking

Webschool News

Disaster Appeals


Red Cross

Environmental News

Space Today

Cassini mission ends with a plunge into Saturn's atmosphere

ESA signs first Ariane 6 launch contract

Soyuz launches new crew to the ISS

Proton launches Amazonas-5

SES awards seven-satellite contract to Boeing for O3b mPower

Dr.Overy's SciGallery

Evolution of the eye...

How could the complex human eye have evolved through natural selection acting o­n small variations?

 

 

 

The complex structure and mechanism of the eye is often the focus of attack by those wishing to invoke the 'intelligent design' argument. The critics argue that something so complex as the eye could not have possibly be the result of random mutations and natural selection. They argue that none of the individual components of the eye enables vision to be possible.  

 

eye

This is indeed a challenge for Darwin's theory of evolution. Yet, scientists have shown that there are scenarios by which, over a long period of time, a complex mechanism as the eye can evolve.
In a pbs video a scientist explains how a simple light-sensitive pigmented spot o­n the skin can undergo a whole number of changes to evolve into the complex structure and operation of  the eye.

Indeed, the eye as exists today does have its faults!  This would not have been the case had it been the result of 'intelligent design' . Blood vessels running o­n the surface of the retina can cause problems with vision when they leak. This is often the case with people with diabetes or high blood pressure. It would have been better if they had been behind the retina, to avoid such complications.

There is a whole range of assorted 'eyes' in living species today, which provide evidence of various stages of evolution of the complex stages of development of the human eye.

Scientists have estimated that the time needed for the development of   a eye as complex as a human eye would o­nly require approximately 364 thousand years.

More details of how the eye could have evolved is located on the PBS website :

 Evolution of the Eye  :  http://www.pbs.org/wgbh/evolution/library/01/1/l_011_01.html

Further resources o­n evolution can be found o­n the www.pbs.org website at  

http://www.pbs.org/wgbh/evolution/library/index.html

 

[end of article]