 About
Fossil Insects |
| About
Fossil Insects |
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| By Garry
Platt (UK)
Email: garry.platt@wgrange.com Web Home page: http://www.gplatt.demon.co.uk Introduction Amber has a strange fascination for nearly all people who come into contact with it. The process by which it is formed is remarkable. Its geological history and its influence on human history are considerable. The earliest known worked pieces of amber were discovered in Southern England near the Cheddar/Creswell crags. The age of these worked beads is between 13,000 and 11,000 years. Today amber can still be found washed up on certain beaches or dug from mines and pits. And the jewellery that is made from the raw material is still highly prized and coveted. From this it can be seen that the association between humans and amber is both ancient and complex. The two are intertwined to such an extent that they have become inseparable.  Formation of Amber Millions of years ago there were huge forests that covered vast tracks of the earth. Some trees within the forests exuded a resin from their trunks and branches; these were the ancient amber trees. A number of theories have been proposed about why the trees secreted so much resin, amongst them are: 1. As a defence mechanism against fungal
or insect attack.
3. As an aid to reproduction and the attraction of insect pollinators. 4. As a reaction to storm or weather damage. 5. *A process linked to growth. *Recent studies conducted in Russia have indicated that the resin may have been discharged more heavily during particular periods of the year and so the resin could well be a bi-product of seasonal growth. (This is true of the Kauri, a species of tree found in New Zealand and which produces enormous amounts of resin which is known as Kauri Gum).Whatever the purpose the resin would collect in layers on the surface of the trees or fall into  pools
of hardening resin at the foot of the trees.
In this particular example of Baltic amber there are more than 42 separate layers of resin present. This was only the first stage in the transformation of resin into amber. The process by which amber changes into resin is complex and not fully understood but a number of basic factors are recognised. The fresh resin would need to quickly become buried in the soil or an anaerobic environment (little to no oxygen present) to prevent its oxidisation. Over the many millions of years that followed a slow chemical change would take place that saw the slow evaporation of volatile turpenes present in the matrix of the resin. You can smell the turpenes in fresh resin. There was also the polymerisation of the resin molecules, i.e. the joining together of the individual molecules into long stable strands. It is only when this process is complete that the resin can be termed amber. In addition to these processes heat and temperature may also be a major contributing factor to the transformational process, but exactly what part they play has yet to be precisely determined.
Here is an example of Colombian copal that has formed into a 45cm long rod by dripping down from a branch or tree trunk. Amber is most frequently found as rough lumps in mines or pits. There are businesses in many countries where amber is found which extract and work the fossil resin into craft goods, jewellery and resin bi-products such as varnish or shellac. This is particularly true of Russia where the extraction and processing has reached industrial proportions using heavy equipment and machinery. Thousands of tonnes are refined and processed in this way. In the Dominican Republic the digging and extraction is done on a much smaller scale and the processes is predominantly done by hand. The quantities however are still significant. In the Baltic region where large quantities
of amber are found it is often washed up on the Baltic shore line. In these
instances it is usually in the form of rounded pebbles or 'cobbles' and
can range in size from tiny grains up to larger pieces 40 cm across at
their broadest part.
Inclusions in Amber
By studying these inclusions it is possible
to learn about ecology and environment that existed at the time the resin
was laid down. There are many different types of inclusions that can be
found in amber these have include: Flies, Spiders, Pseudo Scorpions, Cockroaches,
Termites, Leaf-Hoppers, Beetles, Ants,
Wasps, Bees - The list goes on and most species are represented in amber
collections around the world.
Traces of mammals that lived in these ancient woodlands and not very frequent but hair, feathers and even teeth have been found. Very occasionally a lizard will be tapped in amber and when these are discovered they command high prices when brought to the market. 
Andrew Ross of the Natural History Museum
in London has published a book that helps the developing amber entomologist
identify insect inclusions. The details of this publication are listed
in the bibliography section.
Some Major Locations Lebanon
inclusions. The source of the material is in the Jezzine district and dates back more than 120 million years, early Cretaceous, Hauterivian Stage. This material has been known to exist for more than 100 hundred years but it is only in recent years that systematic and controlled analysis of the material has begun. Following spectrographic analysis of this ancient resin indicates the tree source as araucarian and this has been substantiated by plant remains in the resin which indicate that they may have been Agathis in type.
One of the oldest known termites trapped in amber has been recovered from these deposits and doubtless other even more remarkable discoveries will be made in due course from this site.
The Dominican Republic deposits have been the centre of much research by such eminent scientists as Dr George Poinar and Dr David Grimaldi both of whom have books currently in print. The details of these publications can be found at the foot of this page. Dominican Republic amber dates back to between.
Published books currently available on amber. Anderson, K.B. & Crelling, J.C. (Ed.) 1994.- Amber, Resinite, and Fossil Resins. American Chemical Society, ISBN: 0-8412-3336-5. Beck, C. & Shennan, S. 1991.- Amber in Prehistoric Britain. Oxbow Books, ISBN: 0-946897-30-1 Borkent, A. 1995.- Biting Midges in Cretaceous Amber of North America. Backhuys Publishers, ISBN: 90-73348-40-4. Fraquet, H. 1987.- Amber. Butterworths, ISBN: 0-0408-03080-1 Grimaldi, D.A. 1996.- Amber, Window to the Past. Harry N. Abrams, ISBN: 0-8109-1966-6. Larsson, S.G. 1978.- Baltic Amber - A Palaeobiological Study. Entomonograph Vol. 1 Klampenborg, Denmark, ISBN: 87-87491-16-8 Poinar, G.O. Jr. 1992.- Life in Amber. Stanford University Press, ISBN: 0-8047-2001-0 Poinar, G.O. Jr., 1996.- Discovering the Mysteries of Amber, GEOFIN s,r,l, - Italy, ISBN: Poinar, G.O. Jr., 1999.- The Amber Forest - A Reconstruction of a Vanished World; Princeton Univ Press, ISBN: 0-691-02888-5 Poinar, G.O. Jr. & Poinar, R. 1994.- The Quest for Life in Amber. Addison-Wesley Publishing Company S; ISBN: 0-201-62660-8 Ross,
A. 1998.- Amber - The natural time capsule. Natural History Museum,
London. ISBN: 0-565-09131-X.
Interesting Amber Web Links
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| About
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Amber
can be found which has retained the original shape in which it was formed.
One of these forms are stalactites. In these cases fresh resin has dripped
from a tree branch and gradually set in a stalactite formation.
When
the resin was first formed occasionally animals or plants were trapped
or enveloped by the falling resin. The trapped inclusions where preserved
with remarkable level of detail. When viewed under a magnifying glass the
inclusion appears as though it was trapped only yesterday. The level of
preservation extends down to internal organs and in some instances individual
cells.
