It is commonly accepted amongst scientists nowadays that DNA extraction from a fossilised dinosaur or something that fed upon a dinosaur, is impossible.  However, as I mentioned above, there is a theory, argued by Dr. David Stearn (of the Howard Hughes Medical Institute, USA) amongst others, that it should

be possible to work backwards along the ‘tree of

life’, recreating extinct species from their closest

living relatives as we go, all the way back to the

dinosaurs.  Dr Alison Wollard (of Oxford University’s

department of biochemistry), agrees with this theory

that extinct species can be ‘de-evolved’. 

 

“We know that birds are the direct descendants of

dinosaurs, as proven by an unbroken line of fossils

which tracks the evolution of the lineage from

creatures such as the velociraptor or T-Rex through

to the birds flying around today,” says Dr Woollard.

“The most famous of these is the Archaeopteryx, a

fossil which clearly shows the transition between

feathered dinosaurs and modern birds. 

This evolution implies that buried deep within the

DNA of today’s birds are switched-off genes that

control dinosaur-like traits.” 

The theory is that we could 'rewind’ evolution by

switching these genes back on and using them to guide the development of that bird’s offspring, and its offspring’s offspring, backwards.

“In theory we could use our knowledge of the genetic relationship of birds to dinosaurs to 'design’ the genome of a dinosaur,” said Dr Woollard.

However, despite the theoretical possibility, there are practical obstacles (cost and time being only two) and ethical questions that cannot be ignored.