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Jurassic Park is the epic story of dinosaurs brought back to life in modern day.
In the story, the dinosaurs were regenerated using genetic
techniques to rebuild and recreate many species of dinosaur using their
DNA (the genetic building
blocks). The DNA was supposedly extracted from the blood of ancient mosquitoes
and insects (which had supposedly fed off dinosaur blood all those hundreds
of millions of years ago). These insects, all those millions of years ago, had
become trapped in tree resin. When resin hardens over the years it becomes amber
- which is an incredible preservative agent as it is excludes air or water plus
it contains natural preservative chemicals.
Therefore the theory behind the Jurassic Park story was that these ancient pests
were trapped in a tomb of amber which kept them perfectly preserved and housed
within them genetic information about the dinosaurs, which was then used to
clone them.
Sounds far-fetched huh?
Can scientists rejuvenate dinosaurs from cells trapped inside an insect in
a chunk of amber?
No. Not yet.
However a number of startling and important scientific discoveries have been
found in amber.
Resin flowing from a tree is one of the stickiest substances around - think
of it as organic flypaper) - as it can trap insects, flowers, and small lizards.
Once ensnared in resin's everlasting embrace, these organisms remain frozen
in position as the resin hardens into amber.
Amber is the best preservative for ancient life, and there are many instances
of ancient insects, spiders, lizards, leaves and flowers to mention but a few
that have all been found trapped and preserved perfectly in amber.
Such specimens have been preserved so well, that scientists are able to observe
and study in incredible detail these prehistoric relics, and hence amber is
soley responsible for the existance of vital information about the ancient past.
Ancient relics trapped in amber are able to provide vital information and clues
as to what ancient flora and fauna and life was like, clues such as: their chemistry,
anatomy and 3-dimensional structure, etc... have been preserved beautifully.
Amber is bringing back a treasure-trove of riches for biologists, as amber research has opened new windows on the past.
Insects trapped in amber show what they used to look like and where particular species used to live. A species of termite found in Dominican Republic amber, for example, only exists now in Australia. Thus amber can help uncover animal migration patterns, and reveal information about climate, sea level, environmental conditions, and the presence or absence of other animals and of plants.
The chemical which carries the genetic code - can be recovered from many biological samples, and even from ancient amber. By looking at specific parts of the code, scientists can compare the "spelling" of the code to that of existing organisms (small changes occur through the years in many well-known genes). Then, by using estimates of the rate of change per year, they can calculate whether two samples are from the same species, from closely related species, etc.
These techniques of "molecular genetics" can also be used to identify species
and restructure the tree of life. In other words, they can demonstrate how organisms
are related, based not on their appearance or structure, but on how their DNA
has changed over the years.
Nobody's seriously talking about resuscitating dinosaurs - but some whole organisms
have been recovered from amber.
Raul Cano, a California Polytechnic State University microbiologist, is one enthusiast who is trying his hand at the regeneration of lifeforms trapped in amber. No, he didn't try to bring back a triceratops. But he did try to rejuvenate a life form almost half as old (at least 25 million years), and somewhat smaller - it's a bacterium!
In 1992, Cano announced the extraction and cloning of insect DNA from the Jurassic period, coinciding with the opening of the film "Jurassic Park".
The amber is dated at between 25 and 40 million years old, based on the microscopic fossils found in the geographic strata in which the amber was found.
It's one thing to recover strands of DNA from old amber. But what about recovering entire organisms? And, in the past four years, Cano says he has succeeded in recovering dormant bacteria from ancient bees. The bacteria apparently survived as spores (defined) inside the gut of a bee from amber found in the Dominican Republic. A comparison of the DNA of ancient and modern bacteria appeared to confirm that the bacteria had indeed grown from the ancient spores.
What was the bacteria doing in the bee's stomach?
Bacillus species form symbiotic relationships with numerous bee species. While
the bees provide a home for the bacteria, the bacteria aid metabolic
processes within the bees. When facing starvation, the bacteria undergo
transformation to spore form, he explained
Cano knows lots of people doubt that bacterial spores can live so long, so he spent three years testing and retesting his process before he published his discovery. Raul Cano knew people would doubt that he'd actually resurrected bacteria from bees trapped in ancient amber. So he used a battery of techniques to make sure he wasn't growing modern contaminating bacteria instead (one of his greatest criticisms from skeptics).
Cano claims he resurrected at least 30 to 40 species of bacteria from ancient spores, and grew them on culture plates. Now he's analyzing those bacteria. Most, he says, are members of the genus Bacillus, an ancient, spore-forming group of bacteria that is widely distributed today. Some members of the genus (Bacillus thuringiensis) are used for biological control of insects. The main distinguishing factor of the bacteria he has recreated shows what "may be a new model of cell division." Instead of dividing relatively symmetrically as with most bacteria types, the newly discovered bacterium divides asymmetrically.
Analyzing the chemistry of the organisms, Cano has found a new antibiotic, which will be described soon at a scientific meeting. He's also formed a company (Ambergene) which is trying to find industrial, agricultural and medicinal uses for the chemicals produced by his research. He has also been awarded a patent for the recovery of bacteria and other ancient organisms, including fungi, viruses, pollen, and protozoa, from amber and other ancient resins.
Since their initial success in 1992, Cano and his colleagues have isolated bacteria as old as 135 million years.
However, the current research does not mean scientists are one step closer to reviving dinosaurs, he noted: "It has been known for some time that because of their size, structure and composition, some bacteria can survive as spores for long periods, much as seeds outlive a plant. That is not true of more complex organisms."
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