Richard Charles “Dick” Lewontin (born March 29, 1929) is an American evolutionary biologist, geneticist and social commentator.In a pair of 1966 papers co-authored with J.L. Hubby in the journal Genetics, Lewontin helped set the stage for the modern field of molecular evolution.He is also very well known for his landmark paper ” The Spandrels of San Marco and the Panglossian Paradigm” which he wrote with great Stephen Jay Gould and thus introduced the term “spandrel” to evolutionary theory. A spandrel is something that evolves as the necessary result of another …

One of the important question in the field of evolution is to understand : What makes us humans? It is well approved now that humans and chimpanzees originate from a common ancestor before diverging from each other some 6 million years ago.Charles Darwin was not provocative in saying that we descended from apes ,indeed we are apes in every form our long arms,habits,temperament and tailless bodies. In order to understand better what differs between humans with their closest living relatives chimps ,scientists have sequenced the genome of Chimpanzees in 2005 …

One of the principle objectives of performing a PCR reaction to have DNA amplified with no errors.The amplified product will be of no use if its gets copied with altered bases.
DNA replication ( which forms the crux also in in vitro PCR reaction) in vivo is carried out with high fidelity ,thanks to proof reading ability of the DNA polymerase.During the replication of mammalian genomes ,only one base in about (3 × 10 power 9) is copied incorrectly.Proof reading property of DNA polymerase enables it to ensure a check on …

Shedding some genetically induced excess baggage may have helped a tiny fish thrive in freshwater and outsize its marine ancestors, according to a UBC study published today in Science Express.
Measuring three to 10 centimetres long, stickleback fish originated in the ocean but began populating freshwater lakes and streams following the last ice age. Over the past 20,000 years – a relatively short time span in evolutionary terms – freshwater sticklebacks have lost their bony lateral plates, or “armour,” in these new environments.
“Scientists have identified a mutant form of a gene, …

Large flightless birds of the southern continents – African ostriches, Australian emus and cassowaries, South American rheas and the New Zealand kiwi – do not share a common flightless ancestor as once believed.
Instead, each species individually lost its flight after diverging from ancestors that did have the ability to fly, according to new research conducted in part by University of Florida zoology professor Edward Braun.

The term enhancers is quite a common one in molecular world, which is the DNA element that, upon binding with transcription factors (activators), can enhance transcription. It may be located either upstream or downstream or of the transcriptional initiation site or even in even inthe intron of the gene itself . However, most of them are located upstream. In prokaryotes, enhancers are quite close to the promoter, but eukaryotic enhancers could be far from the promoter.
Mike Levine’s group proposing a new term called as “Shadow enhancers” ,which are …

A post-doctoral position is available in the laboratory of Marie-Anne Felix, Institut Jacques Monod, CNRS- University Paris 7, Paris, France, starting in the spring of 2009. Possible projects include quantitative studies of the inter cellular signalling network involved in C. elegans vulva development and evolutionary studies of vulva development in the Caenorhabditis genus. For interested candidates, please send a letter of motivation, a Curriculum Vitae and a list of three referees.
Marie-Anne Felix e-mail:felix@ijm.jussieu.fr