Neotropical Amber

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Amber From The New World Tropics
© W.P. Armstrong 31 March 2010

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Imagine the following theoretical scenario: The date is 70 million years bp (before present), and an ancient mosquito is sucking blood from a Tyrannosaurus rex. Shortly after dining on the dinosaur's blood, the mosquito becomes trapped in a glob of sticky, resinous sap oozing out of a tree.

About 700,000 centuries later, a scientist drills into the amber tomb and extracts T-Rex DNA from the dinosaur blood cells within the perfectly preserved body of the mosquito. From the DNA blueprint, a T-Rex is cloned. This is essentially the underlying theme behind the story of Jurassic Park.

Microbes In Amber?

In 1992 two independent research teams published their remarkable discoveries about ancient genes (DNA) preserved in amber, and the exciting new field of molecular paleontology officially emerged. George Poinar, a University of California entomologist extracted DNA from a 30 million-year- old stingless, tropical bee preserved in Dominican Republic Amber (Medical Science Research Vol. 20, 1992). In fact, Poinar's earlier research on ancient insect DNA (Science 215, 1982) provided the inspiration (at least in part) for Michael Crichton's book Jurassic Park, followed by the Steven Spielberg blockbuster movie, one of the most popular box office hits of all time. As Poinar's team at Berkeley conducted their research, another team led by David Grimaldi and Rob DeSalle at the American Museum of Natural History extracted DNA from a 30 million-year-old termite entombed in Dominican Republic amber (Science Vol. 257, 1992).

During the summer of 1993, several additional articles about the extraction of DNA from amber appeared in Volume 363 of the prestigious British journal Nature. In an article by Raul Cano of California Polytechnic University, San Luis Obispo, DNA was extracted from a 120-135 million-year-old weevil found in Lebanese amber. This discovery of insect DNA is well within the time frame when enormous dinosaurs roamed the earth. In another article by Cano and Poinar, chloroplast DNA dated at 35-40 million years old was extracted from the leaf of a West Indian locust preserved in Dominican Republic amber. The leaf is from the extinct species Hymenaea protera, the probable ancestor of present-day African and New World copal-producing Hymenaea species.

These remarkable new DNA discoveries in amber may provide the answers to such profound questions as why have insects changed so little during the past 150 million years, while other animals have evolved dramatically. Using sophisticated computer analysis, the precise DNA sequencing of ancient genes can be used to construct phylogenetic trees showing the origin and taxonomic relationship of animals. This information can be correlated with evidence from plate tectonics to show the ancestral migrations of animals and plants as they literally rode on the moving continents. DNA from ancient plants opens up a Pandora's Box of fascinating research, and may shed some light on the rather sudden and mysterious origin of flowering plant species.

In case you are worried about the reality of Jurassic Park, it is very unlikely that a five ton T-Rex or vicious Velociraptor will ever be cloned from DNA preserved in amber. Even if a DNA sample from the stomach of a blood-sucking insect could be identified as the insect's last supper on the skin of a T-Rex, the odds against ever reconstructing a T-Rex are overwhelming. Reassembling the complete DNA genome of a dinosaur from gene fragments trapped in amber would be like trying to reconstruct the complete Encyclopedia Britannica from a cupful of letters in alphabet soup.

However, it may be possible to clone ancient viruses and bacteria preserved in amber. Since they have fewer genes, reconstructing the DNA of a virus or single-celled bacterium is within the realm of today's modern biotechnology. Bringing extinct microorganisms back to life after many millions of years could have some valuable medical implications, such as the origin of present- day disease organisms. There could also be some frightening consequences equal to those of Jurassic Park, such as bringing back to life a serious pathogen--perhaps an AIDS virus that killed off the dinosaurs. The latter scenario is reminiscent of another Michael Crichton book, The Andromeda Strain.

So the next time you gaze into your favorite piece of amber jewelry, think about the DNA of microbes that it might contain, quietly resting in a harmless abiotic state for the past 40 million years.

Amber: Natures Transparent Tomb

   See A Lovely Dominican Republic Amber Necklace
   See Resin Blob Exuding From A West Indian Locust
   See Infrared Spectra Of Dominican Republic Amber
   See Amber In Dominican Republic Sandstone
   See 30 Million-Year-Old Ants Entombed In Amber
   See Photos Of The Remarkable West Indian Locust
   See 30 Million-Year-Old Pseudoscorpions In Amber
   See 30 Million-Year-Old Midge Flies In Amber
   See Copal And Bogus Amber Necklaces
   See A Resinous Poison Oak Stem Cross Section

Since the first records of neolithic man in Europe, approximately 5,000 years ago, amber has been cherished for its natural beauty and mysterious properties. Amber trade routes of the Phoenicians, Greeks and Romans crossed Europe from the Baltic Sea region, where it was found in great abundance. Designated as tree resin by Aristotle, Pliny and others, amber was once thought to be solidified lynx urine, mineralized honey or petrified whale sperm. Although amber has been found throughout the world, one of the most fascinating and little-known deposits of this botanical gem is the New World tropics. Many tree species are known to produce amber, but most neotropical (New World) amber comes from the fossilized resin of extinct Hymenaea protera, an ancient leguminous tree that once grew throughout the Caribbean region, Mexico, Central and South America more than 30 million years ago (see: D.A. Grimaldi, Amber: Window to the Past, 1996). The tropical distribution and chemistry of this beautiful honey-colored amber correlates remarkably well with the present-day West Indian locust (Hymenaea courbaril). Unlike the extinct progenitors of Baltic amber, the West Indian locust is the living descendent of most neotropical amber. And unlike most trees of the New World tropics, the genus Hymenaea allows one to peer into the geologic past--to actually see some of the creatures it was associated with millions of years ago, perfectly preserved in a transparent tomb of fossilized resin. The natural dispersal of this huge canopy tree throughout lowland forests of Central America may have been dependent on large prehistoric elephants that once roamed this region many thousands of years ago. In addition, the widespread distribution of this remarkable tree throughout the Caribbean, Mexico, Central and South America is probably due to its large, woody seed pods that ride the ocean currents of the Western Hemisphere.

Neotropical and African Copal

The generic name Hymenaea is derived from Hymen, the Greek God of marriage, referring to the beautiful green leaflets that always occur in matching pairs. In the evening during the spring flowering season, large, white blossoms appear high in the canopy branches. The large anthers put pollen on the chest and head fur of nectiferous bats that are attracted to the sweet blossoms. The trunk and roots of West Indian locust exude a sticky, yellowish terpene resin that forms hardened globs which become buried in the soil around massive trunks of dead trees. The raw resin is known as Central American copal, and it is used for varnish and as incense. Central and South American copal is also produced by the related genus Copaifera, which includes the highly aromatic balsam-producing trees C. reticulata and C. officinalis. [Another source of balsam resin is the Central American leguminous tree Prioria copaifera. The large, flattened, one-seeded pods of the latter species are commonly washed ashore along Caribbean beaches of Costa Rica.] The hardened subterranean resin known as East African copal, which is commonly used in bead jewelry, comes from Hymenaea verrucosum, a tree that is closely related to the West Indian locust. It was formerly classified in the genus Trachylobium. In Chiapas, Mexico, Dominican Republic, and parts of Colombia and Brazil, the subterranean resin globs of ancient Hymenaea trees have transformed into amber through a remarkable chemical process requiring millions of years. During the polymerization process the volatile mono and sesquiterpenes escape and the nonvolatile diterpenes bond together forming a hard plasticlike polymer that is resistant to natural decay processes and the ravages of time. Unlike copal resins, the amber is unaltered by organic solvents such as alcohol, acetone and ether. Although copals will take a high polish, they contain volatile terpenes that gradually evaporate, causing the surface to become deeply crazed like a dry lake bed. Dr. Jean Langenheim of the University of California at Santa Cruz, the noted authority on plant resins (Science Vol. 163, 1969), has studied amber samples from throughout the world using infrared spectroscopy (IR). When printed by a plotter, the IR's appear like a series of closely-spaced peaks and valleys, with each species of tree having its own characteristic "fingerprint" pattern. Samples of amber from Mexico, Dominican Republic, Colombia and Brazil have IR spectra remarkably similar to raw resin from present-day West Indian locust.

Like an intricate fingerprint identification, the jagged peaks and valleys of infrared absorption spectra (IR) of Dominican Republic amber closely matches IR spectra from present-day resin of West Indian locust (Hymenaea courbaril) and Central American copal incense. [IR courtesy of Professor David Boyajian, Chemistry Department, Palomar College.]

Other New World incenses come from trees of the Torchwood Family (Burseraceae), including Protium copal and "gumbo limbo" (Bursera simaruba). The latter species has a thick, resinous trunk and is closely related to the bizarre "elephant trees" (Bursera microphylla) of the Colorado Desert of Alta and Baja California. The infamous Old World relatives of these trees include frankincense (Boswellia sacra) and myrrh (Commiphora abysinica). In fact, when people of Asia Minor were tapping frankincense and myrrh trees, copal and freshly hardened resins of Hymenaea and Copaifera were burned as incense by native people of Central and South America.

Baltic Amber

For decades Baltic amber has been arbitrarily assigned to an extinct pine (Pinus succinifera) because of the presence of succinic acid; however, IR (infrared spectroscopy) studies show that Baltic amber may be more closely related to resins of broad-leafed conifers of the araucaria family (Araucariaceae). According to J.H. Langenhein (Plant Resins: Chemistry, Evolution, Ecology, and Ethnobotany, 2003), Baltic amber contains pinaceous inclusions (wood fragments and cones) but with araucarian chemical characteristics, so the origin of these vast deposits remains an enigma. Today the only evidence of araucariads in the northern hemisphere comes from amber deposits and petrified wood, such as occurs at Petrified Forest National Park in Arizona. In New Zealand a living araucariad forest of "kauri pine" Agathis australis produces copious amounts of resin that once formed a thriving industry for hard, durable varnishes and linoleum. Large lumps of hardened resin (up to 100 pounds in size) were dug out of the ground in extensive forested areas of North Island. Forests such as this may have once flourished in the Baltic region 60 million years ago. Throughout the world, the most copious resin-producing trees occur in tropical regions. These complex mixtures of terpene resins may serve as a chemical defense against the high diversity of plant-eating insects and parasitic fungi found in the tropics.

Another interesting product from fossilized araucariads is the medieval gemstone known as jet. Jet is a semiprecious gem excavated in Europe and formed by the metamorphosis and anaerobic fossilization of conifer wood buried under sediments in ancient seas. Ancestral forests that metamorphosed into jet date back to the Jurassic Period, about 160 million years ago. Some authors have suggested that these forests were similar to present-day araucaria forests in South America; however, this has not been substantiated in peer-reviewed botanical journals. Coal deposits are often formed from a variety of decayed woods. Chemically, jet it is a hard, carbonized form of bituminous coal with a density similar to anthracite coal. Anthracite can be readily identified by its metallic luster. Jet takes a high polish and has been used for shiny black jewelry for thousands of years. It has a specific gravity of 1.3, almost as hard as the ironwood called lignum vitae (Guaiacum officinale). Jet became very popular during the mid 19th century England during the reign of Queen Victoria, and was often worn to ward off evil spirits and during times of mourning. In the first century AD, the Roman naturalist and writer Pliny described the magical and medicinal attributes of this beautiful mineral. The well known analogy of "jet" and "black" was coined by William Shakespeare in his "black as jet" from Henry VI part 2. One of the most famous areas for the mining of Victorian jet is Whitby on the rugged Northeast coast of England.

Araucariads: Source Of Baltic Amber & Whitby Jet

Other Natural Resins and Gums

Many different species of plants in a variety of families produce sticky saps composed of gums and resins, but most of these substances do not form amber. True gums are polysaccharides composed of many sugar subunits linked together. They are soluble in water and do not withstand the ravages of time. Plant gums are commonly used as thickening agents and emulsifiers, such as guar gum and gum tragacanth. Gum tragacanth is considered one of the world's best natural plant gums. It come from the sap of several species of spiny, shrubby, Middle Eastern locoweeds of the genus Astragalus. It was largely imported from the Zagros Mountains of Iran, when the United States was on better diplomatic terms with that nation. Locust bean gum, a thickening agent in ice creams and salad dressings, comes from the ground seeds of the carob tree (Ceratonia siliqua). Another valuable plant gum is gum arabic, obtained from the spiny, shrubby Acacia senegal of northeastern Africa. In addition to its use in foods, hand lotions and soaps, it is used in fine water colors, inks and confections. It also produces the water-soluble adhesive on postage stamps and the "lace curtain" on the sides of your beer glass. Plant gums also provide the soluble fiber in a healthy diet by absorbing water and adding bulk to the large intestine. Several dietary supplements contain the powdered husks of psyllium seeds from Plantago ovata (Plantaginaceae). Insoluble fiber comes from the indigestible cellulose cell walls of fruits and vegetables. Both types of fiber are beneficial in maintaining a healthy colon, particularly in older adults with diverticulosis. Terpene resins are an entirely different class of chemicals composed of 5-carbon isoprene subunits joined together to form 20-carbon, nonvolatile diterpene molecules. Oleoresins also contain volatile 10-carbon (monoterpene) and 15-carbon (sesquiterpene) molecules, producing the "piney" aroma of these resins. Fragrant monoterpenes and sesquiterpenes also produce the characteristic odors of perfumes, herbs and spices. Resins are often produced within canals or ducts found throughout the stems, leaves, flowers and fruits of many plant families. Resins are insoluble in water--have you ever tried to remove pine pitch from your fingers? Complex polyterpenes include chicle (used in chewing gum) and milky latexes used in the synthesis of vulcanized rubber.

Glistening globs of gum oozing from the branch of an apricot tree (Prunus armeniaca). Although it superficially resembles a terpene resin it is chemically very different. True gums are polysaccharides that will dissolve in hot water. Like resins they probably benefit the plant by sealing off wounds.

Freshly cut stems of poison oak (Toxicodendron diversilobum) and its close relative poison ivy (Toxicodendron radicans) exude a sticky, terpene oleoresin that oxidizes and polymerizes into a shiny black lacquer resembling pruning sealer. The resinous sap is produced in resin canals of the stems, roots, leaves, fruits, and flowers. Cross sections of poison oak stems show distinct concentric annual rings (ring-porous wood). Numerous resin canals appear as tiny black dots and are confined to the phloem layer just inside the bark. Abundant resin canals is one of the reasons poison oak is now placed in the genus Toxicodendron along with poison ivy, poison sumac (T. vernix) and the Japanese lacquer tree (T. verniciflua--the commercial source of natural lacquer). In fact, the Pomo Indians of California used the natural lacquer of poison oak to dye their baskets. The resin canals also contain urushiol, the insidious allergen that gives poison oak its bad reputation. The name is derived from "kiurushi," the Japanese name for the lacquer tree. Urushiol is a general term applied to the toxic substances in the sap causing allergic contact dermatitis in sensitive people. It is actually a mixture of phenolic compounds called catechols, potent, fat-soluble benzene ring compounds with a long side-chain of 15 or 17 carbon atoms. [See "Poison Oak: More Than Just Scratching The Surface" by W.P. Armstrong and W.L. Epstein, Herbalgram Vol. 34, pp. 36-42, 1995.

See A Poison Oak Stem Cross Section

Although most people associate plant resins with pine pitch, it is doubtful that this resin becomes amberized as commonly as the tropical broad-leafed conifers and legumes. Perhaps the pine pitch is not as resistant to microbial decay over vast millennia of time. Although pine pitch may not be a major precursor of amber, it figures prominently in the history of the United States. The settlement of North America was partially due to England's desire to rid herself of dependence on Scandinavian sources of resin-- since the pitch was used to caulk ships and waterproof rigging. When raw pine pitch is distilled the volatile "spirits" of turpentine are removed, leaving a solid residue known as rosin. Rosin has many industrial uses and provides the slight stickiness to help the baseball pitcher grip the ball and hopefully improve the accuracy of the pitch. Rosin is also used on the bows of string instruments to make them slightly sticky, thus creating more friction and enhancing the tone of the music. Other famous plant resins include Japanese lacquer and the fragrant incenses frankincense and myrrh.

Some purists believe that "true" amber must contain 3-8 percent succinic acid (known as succinite) and must come from 50 million-rear-old Eocene deposits of the Baltic Sea region. Caribbean amber contains no succinic acid and is classified as retinite. According to Dr. Langenheim, the presence of nonterpenoid succinic acid is of little value in characterizing fossil resins.

A glob of glistening resin exuded from the trunk of a West Indian locust (Hymenaea courbaril). Hardened resin globs such as this become buried in the soil and after millions of years gradually metamorphose into amber. The raw resin is used for Central American copal varnish and copal incense.

See Photos Of The West Indian Locust

Dominican Republic Amber

The Dominican Republic is second only to the Baltic region in amber production. This West Indian country occupies the eastern two thirds of the island of Hispaniola, and is bordered on the west with Haiti. Dominican amber was actually first reported by Christopher Columbus on his second voyage to the West Indies in 1493. Until the late l970s, most rough Dominican amber was exported to Europe where it became mingled with Baltic amber. Today the Dominican government has prohibited the exportation of unpolished amber to encourage the development of a cottage industry which uses one of the country's few natural resources. Chunks of amber are carefully chipped out of 20-30 million-year-old Miocene/Oligocene sandstones and shales in rugged mountainous terrain accessible only by foot or packburro. Numerous shallow mines are scattered throughout the northern and eastern cordilleras, some which follow a vein more than 25 feet into the mountainside. One story tells of a child who found an eleven pound chunk of amber while planting a coffee shrub. Dominican Republic amber contains about one insect inclusion per 100 pieces, roughly ten times as many insects as Baltic amber. One hypothesis to explain the greater number of insects in Dominican amber is the copious secretion of sticky resin on the bark of the West Indian locust (or its ancestral predecessor). An astonishing array of creatures has been discovered in Dominican amber, including beautifully preserved insects, spiders, bird feathers, mushrooms, an anolis lizard, and a tiny phoretic pseudoscorpion with one claw grasping the leg of a beetle, hitching its last fateful ride to immortality.

Chunks of glossy Dominican Republic amber embedded in 20-30 million-year-old Miocene/Oligocene sandstone. The beautiful amber gems must be carefully chipped out of the sandstone by hand.

These ants became entombed in the sticky resin of the extinct Hymenaea protera about 25 million years ago. The latter resinous tree was the ancestor of modern-day West Indian locusts (H. courbaril). Although a Dominicam Republic amber mine was depicted in the movie Jurassic Park, all the dinosaurs were extinct by 60 million years ago.

A termite embedded in a transparent tomb of fossilized resin known as amber. The piece was sold as Baltic amber, but it probably has a tropical New World origin. The slender, beadlike (moniliform) antennae are quite different from those of ants. Ant antennae are elbowed with a distinct right angle bend. Both insect orders are common in New World amber dating back 25 million years.

Characteristic Elbowed Antennae Of An Ant
30 Million-Year-Old Pseudoscorpion In Amber
See Modern Day Pseudoscorpions On Pine Park
See A Minute Midge In Dominican Republic Amber
See Another Photo Of A Midge Entombed In Amber

Cellular Organelles in Amber

Even cellular structures such as ribosomes, mitochondria, nuclei and cell membranes have been observed in amber using an electron microscope. In fact, fragments of DNA, the genetic master molecule, have been recovered from a 30 million year old termite preserved in amber. This amazing discovery provides a believable theme in the best-selling book Jurassic Park by Michael Crichton. In the story, scientists isolate dinosaur DNA from the stomachs of blood sucking insects that feasted on dinosaur blood just before drowning in a glob of sticky resin. The DNA fragments are then assembled into dinosaur chromosomes. To fill in the missing gaps between fragments, genes from present-day birds, reptiles and amphibians are also used, a technique that results is some unexpected consequences, including sex changes in the resident dinosaur populations. From the DNA blueprint, dinosaurs are cloned and roam an island off the west coast of Costa Rica. Although the genetic engineers thought their dinosaur creations were all female and incapable of reproducing, they are astonished to find egg shell fragments and an increasing dinosaur population within the park. This paradox turns out to be especially serious in the case of the vicious velociraptors who escape to the Costa Rican mainland. The story was made into a movie by Steven Spielberg, with a sequel "The Lost World" to be released by summer of 1997. Although most Baltic and neotropical amber was formed after the demise of dinosaurs, there are deposits of amber from Bornholm, the eastern United States, Canada and Alaska that date back to the Cretaceous and Jurassic Periods (65 to 180 million years ago). This is in the time frame when these marvelous warm-blooded, reptilian-birdlike creatures ruled the earth, and when lush ferns, conifers and palm- like cycads dominated the landscape. Near the end of this fabulous era the stage was finally set for a new age of flowering plants and mammals, recorded for posterity in the sticky resin of ancestral copal forests.

The Demise Of The Dinosaurs

By the time midges and blood-sucking flies were getting stuck in the resin from ancient forests of ancestral Hymenaea protera in the New World tropics, the once great dinosaur era had come to an end. Not only did these incredible animals disappear from the face of the earth, many of the tree ferns and cone-bearing plants they depended on for food also vanished from the land. Many of the once prolific gymnosperm species (such as cycads) were already replaced by a rich flora of flowering plants, including magnolias, figs, breadfruit, palms, oak, willow, ash and maple. In fact, one hypothesis to explain the demise of dinosaur populations by the end of the Cretaceous Period (65 million years ago) is that slow-growing primitive seed plants could not keep up with the ravenous appetites of gigantic herbivorous dinosaurs, such as the sauropods. Enormous sauropods called apatosaurs, including Apatosaurus (also called Brontosaurus) weighed up to 30 tons. Brachiosaurus weighed 30 to 50 tons, and consumed literally tons of vegetation in a week. According to David Lambert (The Ultimate Dinosaur Book, 1993), if Brachiosaurus was warm-blooded, it would have consumed nearly a quarter of a ton of conifer and cycad food each day. One of the largest land dinosaurs of all time was discovered in Patagonia. Named Argentinosaurus, this huge vegetarian was 110 feet long and weighed 100 tons. According to R.M. Alexander (Dynamics of Dinosaurs and Other Extinct Giants, 1989), fossil stomach contents of giant sauropods have been discovered with fragments of woody twigs up to one centimeter in diameter. Large, worn pebbles have also been found near the remains of these huge dinosaurs, suggesting that they swallowed stones and kept them in their stomachs to grind up vegetation (like plant-eating birds). To appreciate the massive size of these herbivorous dinosaurs, compare their weights with modern-day hippos and rhinos at 2-3 tons, and elephants at 6-7 tons. The following is an illustration of Brachiosaurus:

When flowering plants began to dominate the landscape, they edged out the conifers, tree ferns and cycads that the long-established sauropods depended on. The competitive advantage of flowering plants is probably a lot more complicated, and undoubtedly is related to changing climatic conditions and perhaps an enormous asteroid that collided with earth causing a global dust cloud that blotted out the sun for months. In fact, the course of evolution of plants and animals on earth may have changed more than once by such collisions, and some scientists speculate that life itself may have become much more likely from a collision with a water-bearing comet. At any rate, flowering plants possessed many adaptive traits that made them particularly resistant to drought and extreme cold. Some of these sophisticated advancements included more efficient water-conducting cells (vessel elements), advanced leaf and stem anatomy that could withstand environmental extremes, cold and drought-deciduous foliage (which is rather uncommon in today's gymnosperms), perennials with dormant underground rootstocks capable of surviving severe winters, extremely tough, resistant seed coats that protect the dormant embryo inside for prolonged periods, an enormous chemical defense arsenal against disease organisms and herbivores, and an efficient pollination and dispersal system involving complex interactions with animals. Flowering plants have literally colonized every conceivable habitat on earth, including the extensive fast-growing, fire-adapted grasslands of today that support huge herds of grazing animals, and yet many of these vast vegetation types were not around when dinosaurs reached their heyday.

Bogus Amber: Not The Real Thing

There are many amber imitations sold in today's market made of synthetic polymers with the hardness, color and polished appearance of real amber. Although very old, beautiful and valuable, some of the thick, butterscotch-colored beads from Africa are actually made of a hard, plastic-like material. When touched with a glowing, red-hot needle they emit the distinctive odor of burning electrical insulation, instead of the "piney," incense odor of copal and true amber. Many of the large opaque African beads sold as amber are actually copal. In fact, WAYNE'S WORD has seen large chunks of New World copal (probably from the resin of the West Indian locust) commonly labeled as amber in rock and mineral shows throughout the southwestern United States. Although it is a natural, hardened resin that superficially resembles amber, copal is much softer and can readily be penetrated with a hot needle. In addition, the surface of copal may become cracked with time, as volatile terpenes inside slowly evaporate. The nonvolatile terpenes of copal have not polymerized into the hardness of true amber. One is reluctant to try the hot needle test on a lovely necklace because the beads may become irreparably marred. There are also questionable amber necklaces in which the insect inclusions are perfectly aligned in the center of each bead. These alignments suggest that the insects were floated on liquid amber, copal or a polymer imitation, and then submersed by a second liquified layer. When exposed to ultraviolet light (UV) in a dark room, authentic Dominican Republic amber fluoresces intensely in beautiful shades of blue.

Amber Beads Fluorescing Under UV Light
Assorted Necklaces--Including Bogus Amber
C. American Copal & Dominican Republic Amber

The West Indian Locust

The widespread distribution of West Indian locust throughout the Caribbean and the American tropics is probably due to the buoyant seed pods. The large, woody pods do not open and often get washed down rivers into the ocean where they drift ashore on distant beaches. Several plausible theories have been proposed to explain the occurrence of two remarkably similar species of copal-bearing Hymenaea on the isolated continents of Africa and South America, including continental drift and dispersal of seed pods by ocean currents. Evidence from plate tectonics shows that large plates of the earth's crust are slowly moving. It has been estimated that during the Cretaceous and Jurassic Periods, South America and Africa were once connected in a great supercontinent called Gondwanaland. Although the time frame for Gondwanaland is probably too early for Hymenaea, there may have been an ancestral forest throughout this vast land mass that gave rise to today's isolated copal species. A more plausible explanation involves the ocean dispersal of woody Hymenea seed pods from Africa. Adding credibility to the idea of pods floating across the Atlantic Ocean from Africa via the Equatorial and Brazil Currents are the large brown seeds inside which may remain viable even after many months at sea. The hard seeds are sometimes polished and strung into necklaces by Caribbean islanders. In Costa Rica the seeds are known as "guapinol" and are made into polished hardwood pendants. The dark brown coat is sanded off on one side and the smooth ivorylike inner surface is painted with a colorful country scene.

Read About Continental Drift & Plate Tectonics

According to E.L. Little, Jr. and F.H. Wadsworth (Common Trees of Puerto Rico and the Virgin Islands, 1964), the bark of old West Indian locust trees is thick and can be removed in long sheets. It is highly prized by Amazonian Indians for making canoes strong enough to carry 25-30 men. The stripped bark is sewn together at the ends, and the seams waterproofed with resin; a few wooden crosspieces are then fitted in to hold the shape. Decoctions from the bark have also been used to treat dysentery.

Like the edible, malodorous carob pods of the Mediterranean, the seeds of West Indian locust are surrounded by a sweet, tasty pulp. This nutrient-rich meal may serve as a reward to animals that disperse the seeds. However, with the exception of introduced cattle, donkeys and horses, no native mammals can crush the hard, thick-walled pods in their jaws. Livestock apparently like the sweet pulp inside and disperse the hard, viable seeds in their excrement. In areas without livestock, the rotting pods litter the ground beneath large trees. Agoutis, tapirs and peccaries chew open the rotting pods and eat the sweet pulp and seeds, but are not major agents of seed dispersal like the larger hoofed mammals. According to the authority on Central American rain forests, Daniel H. Janzen (Science Vol. 215, 1982), large grazing mammals, including extinct pleistocene elephants called gomphotheres, may have once eaten the pods and dispersed the seeds in lowland forests. In Africa, the large woody pods of related species are quickly devoured by large herbivores. There are other Central American rain forest trees that also appear to be missing their natural herbivorous dispersal agents. Their hard, woody, indehiscent fruits pile up beneath the branches and slowly rot away in the soggy, moldy layer of soil and debris.

See Photos Of The West Indian Locust

Several species of beetles also take advantage of the abundant pods beneath the West Indian locust. According to Dr. Janzen (Costa Rican Natural History, 1983), the larvae of Rhinochenus weevils bore into the pods and mine through the pulp and seeds inside. After consuming the contents of the pods, the fully grown larva cuts an exit tunnel partially through the thick wall before it metamorphoses into a pupa. This insures that the adult weevil can get out of the pod (similar to the exit door on Mexican jumping beans through which the adult moth escapes). In another species of weevil, the adult beetles remain inside the pod until a rodent chews it open. Then they instinctively flee from the pods-- hopefully without being eaten. Although these beetles have been around for thousands of years, their population dynamics may have been much different when large herbivores gobbled up the sweet pods.

Considering the enormous distribution of the West Indian locust throughout rain forests of the New World tropics, there must be countless tons of resin buried in the soil. Although the chemical changes may be relatively unnoticeable in a human lifetime, some of these honeylike globs are undoubtedly slowly metamorphosing into amber. Perhaps scientists millions of years from now will study our present-day Central American flora and fauna, perfectly preserved in nature's transparent tomb. With the rapid advances in biotechnology, the story of Jurassic Park may indeed become a reality with certain life forms--hopefully without the terrifying consequences that were portrayed in the book.

References About Amber:

  1. Allen, J.D. 1976. "Amber and Its Substitutes--Pt. I Hisorical Aspects." The Bead Journal Winter 1976: 15-20.

  2. Allen, J.D. 1976. "Amber and Its Substitutes--Pt. II Mineral Analyses." The Bead Journal Spring 1976: 11-21.

  3. Allen, J.D. 1976. "Amber and Its Substitutes--Pt. III Is It Real? Testing Amber." The Bead Journal Summer 1976: 20-31.

  4. Cano, R.J. and G.O. Poinar, Jr. 1993. DNA From An Extinct Plant. Nature 363: 677.

  5. DeSalle, R., J. Gatesy, W. Wheeler and D. Grimaldi. 1993. DNA Sequences From a Fossil Termite in Oligo-Miocene Amber and Their Phylogenetic Implications. Science 257: 1933-1936.

  6. Grimaldi, D.A. 1996. Captured in Amber. Scientific American 274 (4): 84-91.

  7. Grimaldi, D.A. 1996. Amber: Window To The Past. American Museum of Natural History. H.N. Abrams, Inc., New York.

  8. Grimaldi, D.A. 1993. Forever in Amber. Natural History 6/93: 59-61.

  9. Janzen, D.H. 1983. Costa Rican Natural History. The University of Chicago Press, Chicago.

  10. Janzen, D.H., and P.S. Martin. 1982. "Neotropical Anachronisms: The Fruits the Gomphotheres Ate." Science 215: 19-27.

  11. Langenheim, J.H. 2003. Plant Resins (Chemistry, Evolution, Ecology & Ethnobotany). Timber Press, Portland Oregon.

  12. Langenheim, J.H. 1973. "Leguminous Resin-producing trees in Africa and South America." In Tropical Forest Ecosystems in Africa and South America: A Comparative Review, ed. B.J. Meggers, E.S.Ayensu, and W.D. Duckworth. Smithsonian Institution Press, Washington, D.C.

  13. Langenheim, J.H. 1969. Amber: A Botanical Inquiry. Science 163: 1157-1169.

  14. Poinar, G.O., Jr. and R. Poinar. 1994. The Quest For Life in Amber. Addison-Wesley Publishing Co., Reading, Mass.

  15. Poinar, G.O., Jr. 1992. Life in Amber. Stanford University Press, California.

  16. Poinar, G.O., Jr. and R. Hess. 1982. "Ultrastructure of 40-Milion-Year-Old Insect Tissue." Science 215: 1241-1242.

  17. Rice, P.C. 1987. Amber: The Golden Gem of the Ages. The Kosciuszko Foundation, Inc., New York.

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