Copyright  Meg MawL © 1997 - 2003.  All rights reserved.

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DEFINITIONS

Age:
The AGE of a fossil or geo-time is given as: Thousand Years Ago (KA) or (KYA) OR Million Years Ago (MA) or (MYA).

Ancient History:
The first members of the shark family arose from the evolutionary morass between 350 and 400 million years ago. These creatures were not much larger than a goldfish. Hundreds of millions of years later, one branch of their descendants evolved into the Apex Marine Predator, the Ultimate Killing Machine, the 80,000 pound Chondrichthian called MEGALODON.

Millions of years later the young men of the island of Malta would bring strange objects that they had found in the cliffs to the "Old Ones". These literati named these triangular stones "glossopetra" meaning "petrified tongues of huge vipers".

In 1667, one of the founders of modern geology, Nicolavs Stenonivs [1631-1687, physician, bishop of Hamburg, vicar-apostolic of Denmark, lived in Florence.] noted the similarities between the teeth of the Great White shark and these "Tongue Stones" and argued in his book "Canis Carchariae Dissectum Caput" (The Head of a Shark Dissected) that these ancient objects were, in fact, the teeth of now extinct, giant sharks. His illustrations of these teeth are thought to be some of the first drawings of a fossil.

In 1835 the Swiss naturalist Louis Agassiz named this extinct giant white shark - Carcharodon megalodon (big toothed shark).

Bite Damage:
Megalodon teeth, in being shed or bring torn out during feeding, may have been hit by other teeth in the shark's mouth. This might have occurred by another tooth grazing the unexpelled, shed tooth as the shark closed it's mouth. Another scenario could be that the tooth became imbedded in the prey animal during feeding and was hit during a subsequent bite. These damages almost always show straight, shallow, parallel grooves at odd angles to the "natural" hydration and stress cracking caused by environmental factors during the fossilization process. Fossilized prey animal bones and vertebra can also exhibit these teeth marks.

Blue Mud:
A marine sediment that owes its color to organic matter and iron sulfide.

Borer Clams:
Everyone has seen teeth that have small (and large) holes drilled in the root.  This damage is caused by ancient and modern day Borer Clams who make themselves homes in the fossil material.  As they outgrow their holes, they emerge and drill a larger home.  Fresh water river teeth do not have these holes.  Teeth that are washed downstream to end up near the river mouth can be attacked by these creatures.  Cooper River teeth are widely known for their rich brown color and their Borer holes.

Bourrelet:
[From the French word - "burlet"] literally meaning a cloth band on a helmet or the raised portion of an artillery shell between the ogive and the body.

In megalodon teeth, the thinly enameled "V" shaped area between the bottom edge of the root and the blade on the "display" side. On the "flat" side it also refers to the band shaped area between the root and blade enamel. Megalodon teeth with full, complete bourrelet enamel are extremely rare and large teeth with uncracked enamel are virtually non-existent. Since the bourrelet enamel is thinner than the blade enamel and is over the area of thickest dentin hydration swelling, it is usually the first thing "to go" as the tooth gets weathered and damaged by it's environment.

Chatoyance:
The property of a material to intensify light into a narrow band as in a cat's eye gem or a silk dress. Having a changeable luster or color especially marked by a undulating band of white light.

In megalodon teeth, the enamel (generally on the display side) is coarsely fractured during the hydration phase of the fossilization process. This cracking is generally confined to the area over the underlying, swelling dentin which leaves the band around the edge clean to the naked eye. The stresses set up in this edge area of the enamel produce multiple, internal, microscopic cracks. In some teeth, these internal fractures cause the interference in the light patterns which is called chatoyance (from the french word - "chat" - meaning cat). This characteristic can easily be seen by holding the tooth in strong light with the tip toward you and rotating it downward. The "unfractured" edge band in one plane will be seen to be lighter in hue and coloration than the center, cracked enamel. As the tooth is rotated, the edge band takes on a hue and color that is significantly darker than the center enamel! This is Chatoyance.

Color:
The general base color of the Root, Bourrelet and/or Blade Enamel. In descriptive context, this term refers to an unusual occurrence of a coloration that differs from the usual medium gray to dark gray.

All shark teeth are white when they are lost or shed.  The color that they wind up with when they are found is dependent on the minerals in the surrounding sendiment.  It is not necessarily true that the darker they are, the older they must be.  There are two things that happen.   The blade and Bourrelet enamel (which are the only original materials left) are stained by impurities, much as coffee or tea will stain your teeth.  The internal dentin and root have been entirely replaced with minerals which bring along their own coloration.  Impurities can come from several different places.  If the tooth falls into an area where a river enters the ocean, the sediment picked up by the river covers the tooth.  This sediment can contain many different substances depending on which area of the land it was eroding at the time.

Blue highlights are caused by the presence of magnesium, chromates or iron sulfide in the surrounding sediment in which the tooth is initially buried.

Red, orange and brown coloration is due to iron compounds such as ferrous oxide [Fe2O3] and tannic acid rivers such as the Cooper.

Black base color is very rare and highly prized. [There was one area in a SC river that produced black teeth in 1998 and 1999, but no more are being found there now.]

Yellow color comes from sulfur or compounds of sulfur in close proximity to the fossilizing tooth.

Rare green color comes from copper salts like cupric chloride or cupric sulfate.

Fossil teeth can be found to have base colors of green, black, cream or just about any color imaginable.

Cooper River:
Back in the early 1970's the Cooper River was the original site of the discovery of commercial quantities of C. megalodon teeth on the East Coast.  This murky, tannin stained river has been reduced by the building of dams for the Santee and Moultrie Reservoirs, to a 35 mile stretch (as the crow flies) between Moncks Corner, and Charleston, SC.  There are areas where the river and tidal currents have cut through the Hawthorn Formation and exposed fossil shark teeth.  In the old days the river bed gravel bars were covered with 4, 5 and 6 inch teeth.  Divers only picked up the large, complete teeth leaving the medium and small teeth and the partials.  This river still produces teeth, but in smaller quantities.  These teeth have the characteristic rich reddish brown color and remain some of the favorites of collectors worldwide.

Click here for a general map of the Cooper River from Charleston to Moncks Corner.    Cooper River

Curved:
The mid line of the tooth curves from left to right or right to left as you look at the flat side or the display side. One blade edge may be curved concave and the other curved convex. This generally indicates that the tooth came from the side of the jaw and if pronounced, probably is a Lateral or Posterior. The purpose for this curvature is to inhibit movement away from but allow movement toward the gullet. The prey animal, with movement, can get in deeper but can not as easily get out.

Crinkles:
The blade enamel edge is sinusoidally curved in one or more waves. This is a pathological feature that is rare, but when it does occur, it generally happens near the blade/root junction.

Dentition:
The number, kind and arrangement of teeth in the shark's mouth.

C. megalodon - Anterior,          Click Here to See Photo
C. megalodon - Intermediate,    Click Here to See Photo
C. megalodon - Lateral,            Click Here to See Photo
C. megalodon - Posterior          Click Here to See Photo

Click Here for a full discussion of Dentition and a Drawing of one side of the Shark's Maw.    Dentition

Discontinuity:
An interruption in the normal time-sequence of deposition of rock or soil layers that reflects the geological record.  This could be caused by erosion removing some of the layers or a fault shifting the layers.  Environmental forces such as glaciers, ocean incursions and wind can erode and remove the upper layers.  The gap in time between the exposed layer and later layer deposits is a "discontinuity" or an "unconformity".

Epoch:
A very important division of Geological Time.    See:     MegMawL: Geo-Timeline

Fall Line:
The Fall Line is a geological boundary between a higher upland region and a lower plain.  Rivers in the upland region drop to the plains as falls or rapids.  A fall line is formed in an area where the rivers and ocean have eroded away the soft, sedimentary rocks of a coastal plain more quickly than the older harder, metamorphic or igneous rocks of an upland region.  This line of erosion follows a crooked line along the East Coast of the US.  In the Carolinas, the Fall Line is the boundary between the Piedmont and the Coastal Plain.  In North Carolina it is more properly called the Fall Zone because it is relatively wide in some areas.

Fanged:
Holding the tooth blade edge on, the tooth is curved from back (display side) to front (flat side). This generally occurs only on the Anterior teeth and its etiology and purpose is basically not very well understood. This shape may well enable the "tearing chunks of flesh out of their prey" family of sharks to inflict more of a terrible, fatal wound. This curvature in the "grasping, puncturing, holding, and swallowing whole" family of sharks would be counterproductive.

Feeding Damage:
Worn or broken serrations amid well defined serrations, generally on one edge of the tooth were generally caused by the tooth impacting bone during feeding on a prey animal. Another manifestation of feeding damage is the relatively common tip "nick" and tip "chip". Chips or nicks out of the blade enamel edge are also caused by hitting prey animal bone.

See:    Feeding Damage

Formation:
A FORMATION is a layer of deposited material that could also contain fossils.  This layer has a lower boundary which defines when in time the FORMATION began to form and an upper boundary which defines when the deposition of the FORMATION ended.  The timeframe of the FORMATION is defined by the presence of biostratigraphic, index fossils.  These foraminifera and calcareous nanno fossils such as ostracodes and inoceramid prisms were small organisms which evolved rapidly and were widespread goegraphically, thus their characteristics at a given point in geo-time are well known.

Sometimes formations are separated by a layer of porous material such as sand.  Often this sand contains water and is called an aquifer.  The formations above and below "contain" the aquifer.  Many communities drill through formations into these aquifers and use the wells as a source of water.

Fossilization:
Processes:
There are 6 different ways that parts of ancient creatures become fossils.

The one that we are most concerned with is called MINERALIZATION. This process produces a Pseudomorph of the original object. The enamel of the megalodon tooth is original; the underlying dentin and root have been replaced by other materials.

For a very intensive discussion of this subject, please click on our WebPage:     FOSSILIZATION

Giant White Sharks:
For some reason, when people hear or read the words "Giant White" they confuse this term with "Great White" or vice versa.  A search on the Internet using the phrase "Giant White" will lead you to many pages where the author meant "Great White".

Many Paleoichthyologists believe that the "Great White" lineage of sharks began with Cretolamna appendiculata down through some of the Isurus (Mako) species and ends with the "Great White" Shark - Carcharodon carcharias.  Cretolamna appendiculata was also the common ancestor to the "Giant White" lineage which led down through the Carcharocles line of sharks to the megalodon.

Group:
A GROUP is two or more FORMATIONS that have common characteristics - either closely grouped in geo-time, location or depositional environment.

Horizons:
Horizons are layers of soil and sediment that form approximately parallel to the surface of the land.  These may include the topsoil, subsoil, sand, bolders, shell beds, fossils and finally the underlying bedrock.

Ice Age:
During the long history of the earth there have been many "Ice Ages".  The most recent started about 5 million years ago.  Many scientists believe that we are still in this ice age, although in one of its "warm cycles".  Ice Ages are long geological times that are characterized by colder than normal earth temperatures. To a fossil shark tooth collector Ice Ages resulted in nothing but grief.  During times of intense cold much of the earth's supply of liquid water was tied up in glaciers and ice caps.  This meant that any fish teeth lost and fossilized were buried in sediments far out to sea that are hundreds of feet under the surface of the present day ocean and can never be found by the average collector.  Another loss is that, at the end of an ice age, the glaciers melted and the ocean waters came surging back, scouring the land of fossil formations and dispersing the fossils far and wide.   Some of these fossils were "reformulated" in place in to new formations but many were scattered inland and out to sea.

For an intense explanation of how the climate affects the coastline and fossil deposition see:

THE EFFECTS OF CLIMATE CHANGES ON THE TOPOLOGY OF THE EAST COAST OF THE UNITED STATES AND DEPOSITION OF MARINE FOSSILS


Light Weight:
Some teeth are noticably lighter in weight than other teeth. Third or fourth row teeth are lighter in weight than a similar sized first row tooth. The underlying dentin was not completely formed. The tooth had a larger central pulp cavity. There was less dentin in this area to swell and many times resulted in a "flat spot" in the blade enamel right below the point of the V in the display side bourrelet. Relatively rare - maybe 1 in 250 to 300 teeth found. (We have several fifth row teeth -- nothing but enamel shell; no root, no pulp, no dentin.)

Man verses Megalodon:
Everybody should know that the old films showing the cavemen fighting a dinosaur were bogus.  Dinosaurs went extinct about 60 million years before man emerged as a species.

Is this also true for the megalodon?  Could an ancient ancestor of ours ever have been eaten by a meg?  The answer to this question depends on when you believe man emerged on the earth's Tree of Life.  The last fossil records of the megalodon before it went extinct were teeth found near Ishikawa, Japan, from the late Pliocene Epoch - about 2 million years ago.  Modern man (homo sapiens) has only been around for about 1 million years.  Many scientists believe that Homo habilis was the first "human".  This guy lived sometime between 1.9 to 1.6 million years ago.  Other finds seem to show that "Australopithecus garhi" who lived about 2.5 million years ago was the first toolmaker.  Most of us have heard about "Lucy" - "Australopithecus afarensis" who lived 3.6 to 2.9 million years ago.  Another human ancestor aged 5.8 to 5.2 million years - "Ardipithecus ramidus kadabba" - hominid fossil remains were found at Middle Awash, Ethiopia.  Recently anthropologists have discovered a new species in Chad, Africa, about 1500 miles to the east of the other discoveries.  This creature named "Sahelanthropus tchadensis" seems to show more human than chimpanzee characteristics and lived almost 7 million years ago.

If you frame your beliefs in just the right way, there are plenty of reasons to justify a senario wherein man could have struggled with megalodon.  There is little doubt as to who would have come out the winner.

Megalodon Size:
 Some paleontologists believe that the size of a megalodon can be approximated from the size of one of the front teeth.  Demon, Gottfried et. al.(1);  leading experts on the megalodon, in 1996, developed a formula and a graph that can be used to calculate the length and weight of the beast if the height of the First Anterior (AI) tooth is known. This is simply an estimate based on a derived linear relationship between tooth size and body length and weight.

The length formula is:

TL = [(0.96 X AI-SH) minus 0.22]

Total Length of the megalodon [in meters] = ((0.96) times (AI Slant Height [in cm]) minus 0.22)

MegMawL converted this to more commonly used measurements and we use a simplified and only slightly less accurate version of this formula:

TL = 8 X AI-SH

Total Length [in feet] = 8 times (AI Slant Height [in inches])

If we apply this formula to the largest tooth we have - 7 5/8" (19.37 cm), and we assume that it was an AI and restored correctly, the length of this animal would have been 61 feet. The more complicated formula yields 60.27 feet.

The graph for the weight shows that it would have weighed 96,338 lbs (48.67 tons).

(1.)
Gottfried, Michael D., Compagno,
Leonard J. V., and Bowman, S. Curtis.
1996. Chapter 7. Size and skeletal
anatomy of the Giant "Megatooth" shark
Carcharodon megalodon. pp. 55- 66.
In: Klimley, A. Peter, and Ainley,
David G. (editors). Great White Sharks
the Biology of Carcharodon carcharias
ISBN: 0124150314
Academic Press. San Diego, Cal.

Member:
A MEMBER is a smaller unit of a FORMATION, usually a geographically distinct portion of the FORMATION deposited in the same timeframe.

Mottling:
Coloration that is distinctively different from the base color. Mottling can occur in the Blade Enamel, the Root and less commonly in the Bourrelet. Mottling can be gradual changes in color or very well defined lines or areas.

Nutrient Holes:
 Generally C. megalodon shark teeth have one or more small holes around the center of the display side root.  This holes were where the arteries and veins entered and left the tooth carrying nutrients to the "live" part of the interior.  Fully developed teeth had no nerve tissue as we humans do.  This animal did not have to worry about a broken tooth hurting.  Do not confuse these holes with the larger holes which the Borer Clam made and used as home until he outgrew them.  Some teeth have Nutrient Grooves instead of holes.

Ocean Regression:
 A seaward migration of the shoreline caused primarily by general global cooling and the subsequent capture and removal of water in the form of glaciers and polar ice caps.  In other words, less seawater - more exposed land mass.

Ocean Transgression:
 A inland migration of the shoreline caused primarily by general global warming and the subsequent release of water from glaciers and polar ice caps.  In other words, more seawater - less exposed land mass.

Overlies:
OVERLIES means that one FORMATION lies over another and is therefore younger.

Pathological Features:
Physiologic or anatomic deviations from the norm, i.e., structural abnormalities.

So much happened in the mouth of the shark when it bit into the prey animal that there was a good chance that some of the blood in the water belonged to the predator. Broken bits of prey animal bone, broken and whole shark teeth in the chunks of flesh could easily have damaged the "Tooth Generating Gland" or the "bud" of a new tooth. If that source was damaged, it might have produced a deformed teeth.

SOME DEFORMITIES:

1. Crinkles in the Blade Enamel edge, generally at the
     junction of the Enamel and Bourrelet.

2. Abnormal Curvature or Fang.

3. Nibs on one or both Root Lobes.

4. Malformation of the Root or Root Lobes, Tip, Blade Enamel.

5. Abnormally thick or thin.

6. Multi-tip.

7. Teeth grown together.

Placoid Scales:
 Placoid scales or "dermal denticles" are small, hard, tooth-like structures in the skin of a shark or ray that corresponds to the scales of other fish. They are more pronounced in some sharks than others (ex. Bramble Shark). They have the same structure as a tooth - an outer layer of enamel, dentin and a central pulp cavity.

Shark teeth are actually modified placoid scales as are the "barbs" and "mouth plates" of a stingray.

Pyrite Inclusions:
 Rarely, some megalodon teeth have IRON PYRITE (Fool's Gold, ferrous sulfide or iron disulfide [FeS2]) inclusions that formed in the underlying dentin during the 15,000 year long fossilization process. The only way to expose these beautiful crystals scattered in the dentin is to polish off the overlaying enamel and cementum.

"Reformulated" Formation:
 A fossil formation that has been created mainly out of fossils washed out of other, earlier formations.  This redeposition can be done by the action of ocean wave or river currents.

For a very comprehensive discussion of this topic along with drawings, click on:     Fossil Formations

Restoration:
 Some dealers, in order to improve the appearance of fossilized teeth, add epoxy and coloration to missing areas of the teeth. These teeth are easily spotted by the shine on the enamel or the consistency of the appearance of a section of the root or enamel.

In buying restored teeth you can generally get a better looking specimen, but serious collectors shy away from restored teeth.

Get a statement from the seller that his teeth are not restored, varnished, painted, glued or preserved in any manner. The value of teeth treated in this manner is greatly diminished and they are HARD TO RESELL IF THE POTENTIAL BUYER KNOWS THAT THEY HAVE BEEN ALTERED.

For more information click on:    Restoration

Shine:
 Many of the fossilized megalodon teeth in North America are found as result of eroded matrix. This erosion occurs in rivers and ocean beach "washes". This erosion also causes deterioration in the shine of the blade enamel. This is caused by the "sandblasting" effect of the sediment (mostly sand) carried in the current dulling the finish of the enamel. Most of the Moroccan teeth, for example, do not go through this type of erosion and the blade enamel is quite shiny. Some few land-found, East Coast megalodon teeth escape this type of deterioration and the enamel is judged as having an excellent "shine". Some of our teeth from the St. Mary's River are very shiny because our divers pull them directly out of the matrix formation before the current can tumble them downstream. The land-found teeth from Summerville, Lee Creek, Nazca (Peru) and some areas in Maryland and Virginia have also escaped this dulling process.

In order to show the base color and mottling of the enamel, the individual photographs were carefully taken to avoid reflecting light. The beautiful shine on some of these teeth can not easily be appreciated by looking at the photographs.

Stage (European):
A very important division of Geological Time.    See:     MegMawL: Geo-Timeline

Taxa, Taxon:
The Linnaean system comprises seven major categories, called taxa (singular: taxon, meaning "rank"). Arranged from the broadest, most inclusive category, to the narrowest, most exclusive category, these taxa are:

KINGDOM
PHYLUM
    subphylum
CLASS
    subclass
  superorder
ORDER
FAMILY
    subfamily
GENUS
SPECIES

According to Linnaeus' system, each species is given a unique, two-part name called a binomen. Each binomen consists of a genus and species epithet. The species is the basic unit of classification and the only 'natural' one. All other taxa are arbitrary, and therefore subject to changes due to new data or interpretations.

The species name is NEVER capitalzed; all other tax names are capitalized.

GENUS - Carcharocles;     Species - megalodon

Tooth Size:
 One of the most frequent questions we receive is, "What size shark did my tooth come from?". Others are "Was my tooth from an adult or juvenile?" and "Was it from a male or female?". Another question to complicate the discussion would be "Where in the mouth did this tooth come from?". These are easy questions if we are talking about a 6 7/8 inch tooth. They are extremely hard questions to answer for many of the smaller teeth for these reasons:

We think that the megalodon evolved over a 20 million year period. At the end of this time, megalodon had evolved into the largest it had ever been. Then for whatever reason, the species became extinct. A 6 7/8 inch tooth would have come from one of these animals who lived about 2 million years ago. The shark would have been a mature female, 60 to 70 feet long and weighed 80,000 pounds. It most likely would have been an upper Anterior tooth.

Let's suppose that the species started out 22 million years ago as a descendant of Carcharocles chubutensis. Let's also suppose that a mature adult of that time reached a length of 25 feet. The largest tooth in her maw would only have been about 2 3/4 inches in slant height.

How do we describe the animal that a 3 inch tooth came from? Was it from a mature shark that lived 20 million years ago or a juvenile that lived 6 million years ago? Further complications come from changes due to ontogenetic stages in the development of an individual shark and species variation due to relative geographical isolation.

One of the ways we could be relatively comfortable with an intelligent speculation would be to date the strata that the tooth came from. Most of the river teeth and all of the teeth from "REFORMULATED" formations can not be dated in this manner because of the absence of "index fossils" or the mix of "INDEX" fossils that originated in the original layers that were "reformulated".

********
A word or two about "Carbon Dating". You can't date material that has no radioactive material in it.  In archaeological "digs" they often depend on things containing CARBON that are in the same geological layer to DATE the artifacts they find there.  An example would be the charcoal remains of the "campfires" in the same strata of the bones they are trying to date. If the bones are not too old, they still have some organic compounds (material containing carbon-14) present and dating is possible.

Radiocarbon Dating can not be used to date megalodon teeth because the "half-life" of carbon-14 is 5,568 years and after 55,000 years, most of it has disintegrated into nitrogen-14.    (Carbon-12 is the "common", non-radioactive form of carbon that we are most familiar with - like pencil leads.   C13 and C14 are isotopes.)

Radiometric Dating can utilize other elements like potassium and argon to date older layers, but these are generally associated with volcanic ash.  If there were no nearby volcanos during the time the fossil layer was being deposited this method can not be used.
********

In summary, there are no easy answers to these questions. Sadly, what we know about this magnificent beast is greatly outweighed by what we do not.

Unconformity:
An interruption in the normal time-sequence of deposition of rock or soil layers that reflects the geological record.  This could be caused by erosion removing some of the layers or a fault shifting the layers.  Environmental forces such as glaciers, ocean incursions and wind can erode and remove the upper layers.  The gap in time between the exposed layer and later layer deposits is a "discontinuity" or an "unconformity".

Underlies:
UNDERLIES means that one FORMATION lies under another and is therefore older.

Velvet Enamel:
The blade enamel instead of being shiny is more like suede leather or velvet material.  This is very unusual and occurs in only a few locations like the teeth from some sections of the St. Mary's River.  This characteristic is thought to be caused by microscopic cracks in the enamel surface in addition to the large swelling cracks.

Zone:
The term ZONE refers to the fundamental unit of biostratigraphy and also to a notation used by scientists to define a time period of a FORMATION.  The timeframe of the ZONE is defined by the presence of characterized, Index or Guide Fossils.  Nannofossils such as foraminifera, ostracodes, and inoceramid prisms are used to define certain zones.  These were small organisms which evolved rapidly, thus their characteristics at a given point in geo-time are well known.

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Copyright  Meg MawL © 1997 - 2003.  All rights reserved.