Darwin : The Genius of evolution
Darwin -The genius of evolution is the channel dedicated by BBC to celebrate this special year of evolution.As everyone knows this year most of us are celebrating Charles Darwinâ€™s scientific ideas and their impact around his two hundredth birthday on 12 February 2009. Ever since the first publication of his magnum opus “on the Origin of species ” in 1859 where he explained his remarkable theory of evolution by Natural selection, which even 150 years of publication still inspiring many scientists to understand completely how life originated and evolved on our planet. Obviously Darwin didn’t / could not known everything about mechanism of evolution ,but scientists of present day leaving no stone untouched to continue the legacy of great Charles Darwin. Researchers have held his brilliant ideas up to scrutiny, and tried to fill in the gaps in evolution theory. This channel on Drawin by BBC offers many interesting things for students but unfortunately it can be viewed only in UK ( at least i being in France cant view the videos and maybe its similar situation in other countries)
There are many others blogs where Darwin is being discussed actively and the controversial cover of latest issue of New scientist ” which reads “Darwin was wrong” leads the pack. There is excellent debate going on about science journalism on evolutionblog and other famous blogs like sandwalk – Pharyngula also discussed this issue.
Its pretty sad to see headings as misleading as this one and that too on the cover of a reputed science magazine like new scientist , just to increase some sales. Its not a surprise that Darwin was wrong and in fact he was wrong at many places but he cant be blamed for all those as he did not have any knowledge about the science of microbiology and molecular evolution at that time.
But keep in mind ,the two biggest ideas in Natural selection and common descent survived all the tests for more than a century, speaks volumes about the brilliant man and his insights on subject.
Graham Lawton’s article “Why Darwin was wrong about the tree of life “ talks about horizontal gene transfers in bacteria and consequences of that on tree of life. The article somewhat justify such a headline ,which talks about some very valid points that Darwin didnot and could not know , but definitely these things doesn’t go against the theory of Darwin but just fills in the gaps occurring in tree of life.
The basic idea is that as Darwin’s tree of life in Origin of species is based on assumption that genes are only transferred vertically. To simplify, genes pass from parent to offspring, but not from sibling to sibling. If unrelated organisms are somehow able to swap genes back and forth, then the tree does not capture much of what is important in the evolutionary process.
Horizontal gene transfer (HGT), also called as Lateral gene transfer (LGT), is any process in which an organism incorporates genetic material from another organism without being the offspring of that organism. By contrast, vertical transfer occurs when an organism receives genetic material from its ancestor, e.g. its parent or a species from which it evolved. Since its discovery in 1959 and later due to some excellent work by Michael Syvanen has shown us lateral gene transfer exists, has biological significance, and is a process that shaped evolutionary history from the very beginning of life on earth.
So with the occurrence of horizontal gene transfer in single celled organisms indicates the base of the tree looks more like a web. As correctly pointed out by Jason Rosenhouse @ Evolution blog that Recognizing the importance of HGT has opened up exciting new avenues of research for biologists, and has shown that evolutionists of the past had been unnecessarily limiting their options in explaining the evolutionary process. However to be fair with the authors who make some really valid points which enhances our knowledge of evolutionary theory and in no way rules out the basis of the Darwin’s theory of evolution instead makes it even strong.(Read the clarification of author regarding the headlines at Sandwalk ) But with such a strong headline tilts the balance more in favor of headline than the real content. To be honest most people read just the headline and few lines than the whole article. So i believe that editors should be more careful in selecting the titles especially on subjects like evolution which can send wrong signals to students.
Some important links for further reading :
Update : Read what Ryan gregory has to say on this topic !!! (1228)