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Composition of Whale Teeth


Shellseeker

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I have a focus on whale today because I recently obtained a few. This generally leads me to trying to understand and identify my finds.  This in turn leads to questions.  What is Whale Ivory?  When I can not find answers or at least thoughtful discussion elsewhere, thanks for TFF. :fistbump:

I found a PDF here: https://www.cites.org/sites/default/files/eng/resources/pub/E-Ivory-guide.pdf

CITESwhaleIvorydefinition.JPG.7c78d5012246a0ca1b815f35ef5dc9c0.JPG

 

Nothing in the above definition of Whale Ivory ever uses the word "Ivory".  What exactly is the whale Ivory?

Modern Whale tooth -- Is the slightly yellow tip the enamel?  Is the Cementum covering the Ivory?

5c421400de9c3_375906_VIEW02_02.thumb.JPG.df43855f8f9a792be6e1cea96b8da446.JPG

 

What about Fossil whale teeth like this Scaldicetus: The tip enamel is easily seen. Is the outer covering Cementum or Ivory or both?IMG_0078largewhaletooth.jpg.fd78aca1fcebc259003981709d913d9f.jpg

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16 minutes ago, Al Dente said:

Ivory = dentin.

I believe that you are correct.  It makes sense but it is not well documented.

From above:  The average height is approximately 20 centimeters.  is not correct. Sperm whale teeth range between 10 and 20 centimeters.  An average length would be 15 centimeters.

So, for modern whale teeth (Sperm & Killer),  Ivory/Dentin wraps the enamel, and Cementum wraps the Dentin. I make an assumption that the same holds for Dwarf and Pygmy Sperm Whales.  In most modern cases, the enamel is not visible or is present as yellowish caps on the Sperm & Killer whales.

This (mostly) applies equally to the fossilized teeth of Miocene whales or does it?.

This is Kogiopsis. I can "see" dentin banding just under the thin layer of cementum. I am wondering about enamel.

IMG_2914Whale.JPG.a51e7ca6729639fce94e4ffd67a059a0.JPG

 

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" It is reasoned by analogy that identification of teeth with enamel crowns involves the same set of problems that are posed by enamel-free teeth that have already been explained
above. "  - (see document )

 

" In fact , there exist at least three distinctly different morphotypes of enamel-crowned teeth in the Lee Creek Mine collections. The first of these morphotypes resembles those that were referred by Abel to the genus Scaldicetus (Figure 91 a-e). Menesin  and Tavani (1968) have provided an excellent series of illustrations displaying the wide variety of large, enamel-crowned teeth from Europe, including some of the holotypes of Du Bus. These are exclusively gibbous-rooted forms with prominent crowns that are covered with bold rugosities. Typically the dentinal core in this kind of tooth is a long conical structure that broadens crownward, and is surrounded by a thick coat of cement that gives the root its gibbous form. The shape of the underlying dentinal core is therefore not ordinarily expressed by the external appearance of the root. This type of configuration is also characteristic of teeth of Ontocetus oxymycterus Kellogg, 1925, which is now Scaldicetus  oxymycterus (see Kohno and Ray, this volume, pages 60-61). "

 

" At least four apparently distantly related, mid-size fossil physeteroid species are known to have possessed teeth without enamel. They are Orycterocerus crocodilinus Cope, 1868, of Miocene age from Maryland and Virginia, Aulophyseter morricei Kellogg, 1917, of Middle Miocene age from California, Kogiopsis floridana Kellogg, 1929, of Pliocene age from Florida, and Physeterula dubusii Van Beneden, 1877, of Middle Miocene to Early Pliocene age from Europe. Although these taxa can be easily distinguished from one another by the sizes and shapes of their teeth, striking similarities in dental character of certain of these fossil types overlap with those of species in the two living physeteroid genera, Kogia and Physeter, which also lack enamel. "

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22 minutes ago, Shellseeker said:

So, for modern whale teeth (Sperm & Killer),  Ivory/Dentin wraps the enamel, and Cementum wraps the Dentin. I make an assumption that the same holds for Dwarf and Pygmy Sperm Whales.  In most modern cases, the enamel is not visible or is present as yellowish caps on the Sperm & Killer whales.

Killer whales are large dolphins and have a dolphin type tooth that doesn’t grow (like most mammals). It has an enamel covering to its teeth but killer whales usually have very worn teeth. Sperm whale teeth grow throughout their lives. They have a small amount of enamel on the tips of their teeth that quickly wears off. Here is a pictue I found on the internet that shows a sperm whale tooth in cross section. I think in modern teeth it is difficult to tell the difference between the dentin and the cementum but it is obvious in fossil teeth.

071465F7-B051-4AAA-85A0-6B732DABE66E.png

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6 hours ago, Al Dente said:

Sperm whale teeth grow throughout their lives. They have a small amount of enamel on the tips of their teeth that quickly wears off.

So I have one modern tooth, which has a yellow tip.  I read somewhere that the yellow tip on some modern sperm whale tooth is enamel. I will try to find that statement, but I am running out of time until Saturday night. On this tooth, I am thinking all I am seeing is cementum and enamel, no dentin/ivory..  Is that correct? Thanks for the info.  
IMG_2481Christmas2015ModernWhaleScrimshaw.jpg.4107027ec3b40b49bfc6fc7fd6d3a477.jpg

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6 hours ago, abyssunder said:

" At least four apparently distantly related, mid-size fossil physeteroid species are known to have possessed teeth without enamel. They are Orycterocerus crocodilinus Cope, 1868, of Miocene age from Maryland and Virginia, Aulophyseter morricei Kellogg, 1917, of Middle Miocene age from California, Kogiopsis floridana Kellogg, 1929, of Pliocene age from Florida, and Physeterula dubusii Van Beneden, 1877, of Middle Miocene to Early Pliocene age from Europe.

It will take me time to read to read and understand the document. I have 30 whale teeth from Bone Valley mines and the Peace River watershed.  I know I have multiple Kogiopsis floridana.  It would seem I should not have the other teeth, but I have a lot of other variations that do not seem to be Kogiopsis...

Is this BV Whale Kogiopsis ? or is that enamel on the tip? I have a lot of reading and thinking to do....and that's good :D:D

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7 hours ago, Shellseeker said:

So I have one modern tooth, which has a yellow tip.  I read somewhere that the yellow tip on some modern sperm whale tooth is enamel. I will try to find that statement, but I am running out of time until Saturday night. On this tooth, I am thinking all I am seeing is cementum and enamel, no dentin/ivory..  Is that correct? Thanks for the info. 

I think most teeth used for scrimshaw have been heavily sanded to smooth out the tooth before carving. I think if there was any enamel on the tooth it would be sanded off because enamel would be difficult to carve, it is much harder than the dentin or cementum.    I replied before that ivory is the same as dentin, I would think for carving purposes the term ivory would also include the cementum since it looks the same on recent teeth and probably carves just the same. The same goes for walrus and elephant ivory which are also constantly growing teeth.

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Hey Jack, cool additions/finds. Interesting stuff!, just wish I ran into them once in awhile...

 

Regards, Chris 

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On 1/18/2019 at 4:09 PM, Al Dente said:

Killer whales are large dolphins and have a dolphin type tooth that doesn’t grow (like most mammals). It has an enamel covering to its teeth but killer whales usually have very worn teeth. Sperm whale teeth grow throughout their lives. They have a small amount of enamel on the tips of their teeth that quickly wears off. Here is a picture I found on the internet that shows a sperm whale tooth in cross section. I think in modern teeth it is difficult to tell the difference between the dentin and the cementum but it is obvious in fossil teeth.

Just searching and collecting links/photos to provide data. In this case on Yellow tips for Sperm whale teeth.. Photo in the jaw, all teeth yellow tips. Did not copy photo here, because Bristolpress trying to sell it

http://www.bristolpress.com/BP-State/328718/connecticut-man-pleads-guilty-to-trafficking-sperm-whale-teeth

Another:

Stranded-sperm-whale-teeth-detailYellow.jpg.373eb0ae775a3e2174f96cd81aa0bfd4.jpg

 

So, sperm whale teeth MAY have yellow tips, but not common in photos on internet. It might be enamel, but also could be dentine.

https://www.whalefacts.org/what-are-a-whales-teeth-made-of/

Quote

..

When it comes to the materials that make up a whales teeth the outer layer of the toothed whales teeth composed of cementum cells (a specially calcified substance) which overlay dentine cells.

Assuming the cementum is removed from the whales teeth you would be able to see the layer of enamel underneath the cementum.

 

Chris,

I have purchased the vast majority of Bone valley teeth that I post. In 10+ years, I have found 11 whale teeth in the Peace River or its tributaries. That make them exceedingly rare, but I do admit that I do not know a single other fossil hunter in SW Florida who has found as many...

@Plantguy

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On 1/18/2019 at 4:03 PM, abyssunder said:

" It is reasoned by analogy that identification of teeth with enamel crowns involves the same set of problems that are posed by enamel-free teeth that have already been explained
above. "  - (see document )

 

" In fact , there exist at least three distinctly different morphotypes of enamel-crowned teeth in the Lee Creek Mine collections. The first of these morphotypes resembles those that were referred by Abel to the genus Scaldicetus (Figure 91 a-e). Menesin  and Tavani (1968) have provided an excellent series of illustrations displaying the wide variety of large, enamel-crowned teeth from Europe, including some of the holotypes of Du Bus. These are exclusively gibbous-rooted forms with prominent crowns that are covered with bold rugosities. Typically the dentinal core in this kind of tooth is a long conical structure that broadens crownward, and is surrounded by a thick coat of cement that gives the root its gibbous form. The shape of the underlying dentinal core is therefore not ordinarily expressed by the external appearance of the root. This type of configuration is also characteristic of teeth of Ontocetus oxymycterus Kellogg, 1925, which is now Scaldicetus  oxymycterus (see Kohno and Ray, this volume, pages 60-61). "

 

" At least four apparently distantly related, mid-size fossil physeteroid species are known to have possessed teeth without enamel. They are Orycterocerus crocodilinus Cope, 1868, of Miocene age from Maryland and Virginia, Aulophyseter morricei Kellogg, 1917, of Middle Miocene age from California, Kogiopsis floridana Kellogg, 1929, of Pliocene age from Florida, and Physeterula dubusii Van Beneden, 1877, of Middle Miocene to Early Pliocene age from Europe. Although these taxa can be easily distinguished from one another by the sizes and shapes of their teeth, striking similarities in dental character of certain of these fossil types overlap with those of species in the two living physeteroid genera, Kogia and Physeter, which also lack enamel. "

 

1st of all, THANKS for 5 pages of this document.  I have spent some time trying to comprehend the information it provides. On page 236, it starts with earbones of Kogiinae and I had recently found an earbone I thought was river dolphin, but now realize it could be Kogiopsis. Kogiinae_Periotic.JPG.02acd7c23c7fcd8ffbdba4027f9fc0c3.JPG

On pg 237, the paper discusses those whales without enamel:

Quote

" At least four apparently distantly related, mid-size fossil physeteroid species are known to have possessed teeth without enamel. They are Orycterocerus crocodilinus Cope, 1868, of Miocene age from Maryland and Virginia, Aulophyseter morricei Kellogg, 1917, of Middle Miocene age from California, Kogiopsis floridana Kellogg, 1929, of Pliocene age from Florida, and Physeterula dubusii Van Beneden, 1877, of Middle Miocene to Early Pliocene age from Europe.

In looking at my Florida whale tooth collection,  I naturally have examples (as expected) of Orycterocerus and Kogiopsis, but not Aulophyseter or Physeterulla. My goal is to sort Florida obtained fossil whale teeth based on the best available scientific papers on differentiating characteristics (like enamel or no enamel).

also on page 237:

Quote

Although these taxa can be easily distinguished from one another by the sizes and shapes of their teeth, striking similarities in dental character of certain of these fossil types overlap with those of species in the two living physeteroid genera, Kogia and Physeter, which also lack enamel. "

In the previous post, I quoted internet sites and showed photos indicating Physter indeed does have enamel under the cementum and dentine. I am not positive, but right now , I am on the "lacks enamel" side.  I think the yellow tooth tips are actually dentine.

 

Page 288 provides discussion of Enamel_capped whale teeth.

Quote

In fact , there exist at least three distinctly different
morphotypes of enamel-crowned teeth in the Lee Creek
Mine collections. The first of these morphotypes resembles
those that were referred by Abel to the genus Scaldicetus
(Figure 91 a-e).

.......

The second morphotype among the teeth with enamel_covered
crowns ( Figure 92 a-c) lacks the rugosities on the
enamel, and possesses a dentinal core that broadens rootward,
with its enveloping coat of cement nearly uniform in thickness.
The external surface of the root therefore has the same
form as the underlying dentinal core. One specimen that was
illustrated by Menesini and Tavani (1968: pI. t 5, fig . 4 a,b)
shows this sort of character.
The third morphotype among the teeth with enamel-covered
crowns is a small, slender, fusiform to conical tooth that
is comparable in shape to those of Orycterocelus crocodili-
nus (USNM 22926), but with a crown that is covered with
smooth enamel (Figure 93 a-c).

I believe that I have Florida based whale teeth that meet the definitions of Morphotypes #1 and #3.

 

Whitmore and Kaltenbach, 2008. Neogene Cetacea of the Lee Creek Mine, North Carolina. pp. 181-269. In: Ray, Bohaska, Koretsky, Ward, and Barnes (eds.), Geology and Palaeontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication 14.

 

Great paper. I will purchase it. I can leverage it to create some great pigeonholes and sort my whale tooth collection to find the ones that do not fit any definition. :D:D

 

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1 hour ago, Shellseeker said:

1st of all, THANKS for 5 pages of this document.  I have spent some time trying to comprehend the information it provides. On page 236, it starts with earbones of Kogiinae and I had recently found an earbone I thought was river dolphin, but now realize it could be Kogiopsis. Kogiinae_Periotic.JPG.02acd7c23c7fcd8ffbdba4027f9fc0c3.JPG

The resemblance may be good. I'm surprised how close they are. :)

 

I can't remember who posted the document on TFF a few years ago, maybe Bobby, but I'm not sure. I'm glad it helps.

 

You made a great work here opening the "Pandora's box", Jack! :dinothumb:

 

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23 minutes ago, abyssunder said:

The resemblance may be good. I'm surprised how close they are.

 

1 hour ago, Shellseeker said:

t now realize it could be Kogiopsis.

Sorry to be a disenter, but they do not match in My opinion.

Also, You need to match them from other angles, not just one view.

Darwin said: " Man sprang from monkeys."

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50 minutes ago, ynot said:

 

Sorry to be a disenter, but they do not match in My opinion.

Also, You need to match them from other angles, not just one view.

Tony,

Here is another view.  It is difficult to line up photos taken from slightly different angles. There are lots of similarities including the size.  What are the differences that you are seeing ? It would seem likely that these 2 periotics are from related species. I am amazed that we are looking at a periotic on the right that is slightly over 4 cm.

Kogiinae_Periotic2.JPG.128bf3e26574f3bf8aaa4dc90868a78c.JPG

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Hey Jack, I think they are similar as well. 

Here's a doc that has some additional photos and for documentation purposes here's the link to the 1929 info you already mentioned...

 

PYGMY SPERM WHALES (ODONTOCETI, KOGIIDAE) FROM THE PLIOCENE OF FLORIDA AND NORTH CAROLINA

JORGE VELEZ-JUARBE,* ,1,2,3 AARON R. WOOD,2,4 and CATALINA PIMIENTO2,5,6

Journal of Vertebrate Paleontology e1135806 (10 pages)

https://repository.si.edu/bitstream/handle/10088/28338/2016 Pimiento JVertPaleo.pdf?sequence=1&isAllowed=y

 

AMERICAN MUSEUM NOVITATES Published by Number 389 AmeRICANMUSEUM OF NATURAL HISToRY Dec. 5, 1929 56.9, 53K (1183: 75.9) A NEW FOSSIL TOOTHED WHALE FROM FLORIDA BY REMINGTON KELLOGG

http://digitallibrary.amnh.org/bitstream/handle/2246/3135/N0389.pdf;jsessionid=C42D3A2D88251C516492704CA42C70CE?sequence=1

Regards, Chris 

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13 minutes ago, Shellseeker said:

What are the differences that you are seeing ? I

Tried to circle the areas in red. Some may be different from angle viewed.

Kogiinae_Periotic.JPG.02acd7c23c7fcd8ffbdba4027f9fc0c3.JPG.35145776a73f62ede0bdb784b740a338.JPGKogiinae_Periotic2.JPG.128bf3e26574f3bf8aaa4dc90868a78c.JPG.728ab893a958d7a6680681fcf404684c.JPG

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Darwin said: " Man sprang from monkeys."

Will Rogers said: " Some of them didn't spring far enough."

 

My Fossil collection - My Mineral collection

My favorite thread on TFF.

 

 

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12 hours ago, Shellseeker said:

On page 236, it starts with earbones of Kogiinae and I had recently found an earbone I thought was river dolphin, but now realize it could be Kogiopsis.

I'm no expert on petrosals but I have attempted to identify the ones in my collection (I've found over 100). I agree that yours is in the Family Kogiidae. The Lee Creek vol. 4 identifies these petrosals as Kogiinae, incertae sedis. I think these are the easiest to identify, at least for me. The two main characteristics listed in vol. 4 are the flattened, spatulate posterior process and the anterior process that terminate in two points. Your petrosal displays these two features. Other petrosals in my collection don't have as large of a posterior process as the Kogiinae petrosal have. Here are some of my Kogiinae petrosals. Note that C and F are rotated more than the others, making the posterior process look smaller than they really are. The red arrows point to the two points on the anterior process. Petrosal G comes from Greens Mill Run, the rest are Lee Creek.

otoflashLABELED.JPG

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11 hours ago, Plantguy said:

Hey Jack, I think they are similar as well. 

Here's a doc that has some additional photos and for documentation purposes here's the link to the 1929 info you already mentioned...

:fistbump::fistbump:

Thanks Chris,  I love scientific PDFs,  especially on fossils that I might or might not have.

NICE picture of Kogio periotics in the 1st PDF, Jack

NEW, Chris. I was about to reply to Al Dente, and this was sitting from last night in my submit buffer.  :headscratch::headscratch:

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3 hours ago, Al Dente said:

I'm no expert on petrosals but I have attempted to identify the ones in my collection (I've found over 100). I agree that yours is in the Family Kogiidae. The Lee Creek vol. 4 identifies these petrosals as Kogiinae, incertae sedis. I think these are the easiest to identify, at least for me. The two main characteristics listed in vol. 4 are the flattened, spatulate posterior process and the anterior process that terminate in two points. Your petrosal displays these two features. Other petrosals in my collection don't have as large of a posterior process as the Kogiinae petrosal have. Here are some of my Kogiinae petrosals. Note that C and F are rotated more the others, making the posterior process look smaller than they really are. The red arrows point to the two points on the anterior process. Petrosal G comes from Greens Mill Run, the rest are Lee Creek.

Al Dente,

Thank you. I had found this petrosal as a land find a couple of months back and thought it strange that the only teeth I had found were likely Kogiopsis, but had this river dolphin earbone. I note that yours and mine BOTH seem small for what should be 15-20 foot whales.  I took a few more photos.  The land find on the left is 37 mm, a Peace River find on the right 33 mm. It is almost impossible to get River petrosals at this level of detail ..mostly they are severely worn.

5c4740c8772e8_IMG_4614cr(3).thumb.jpg.01ac9f39388bf378886ff3eba22edacf.jpg5c4740c7309ff_IMG_4614cr(1).thumb.jpg.6028e925d5dc2401673007dab65c297e.jpg

I was eliminating these as "whale" due to size.  About a year ago, I found a Peace River Bulla in great shape and stuck it into my "dolphin" earbone collection at 37 x 22 mm.

Do you happen to have a collection of Lee Creek Kogiinae Bulla earbones?

BullaMerge.thumb.jpg.0cbeca598769f0efcb254e83cf50803a.jpg

Finally, I have not seen @Harry Pristis   comment and I value his expertise and knowledge.  Jack

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30 minutes ago, Shellseeker said:

note that yours and mine BOTH seem small for what should be 15-20 foot whales.  I took a few more photos.  The land find on the left is 37 mm, a Peace River find on the right 33 mm.

Jack-

our petrosals are actually large compared with modern Pygmy Sperm Whales (Kogia breviceps) which have petrosals between 26.2 and 38.5 millimeters, and with modern Dwarf Sperm Whales (Kogia Simus) which have petrosals between 24.2 and 27.5 millimeters. From what I’ve been told by several knowledgeable people is petrosals don’t grow much after the whale or dolphin is born. The only part that grows is the posterior process.

 

The range in size for Lee Creek Kogiinae petrosals is 29 to 46 millimeters, a large range which suggest more than one species. I have a lot of bullas from Lee Creek but have never tried to identify them. Most of my bullas are damaged due to their fragile nature.

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3 hours ago, Al Dente said:

The range in size for Lee Creek Kogiinae petrosals is 29 to 46 millimeters, a large range which suggest more than one species. I have a lot of bullas from Lee Creek but have never tried to identify them. Most of my bullas are damaged due to their fragile nature.

Thanks for the additional info on size.

Since the UofF Pomatodelphis inaequalis Bulla below was found within 5 miles of the Peace River example I showed above, and they look this similar:

5c477e27d9449_PomatodelphisinaequalisBullaSbyS2.thumb.jpg.dc60381f54a1d44560daf5fd4e69f68e.jpg

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9 hours ago, Shellseeker said:

:fistbump::fistbump:

Thanks Chris,  I love scientific PDFs,  especially on fossils that I might or might not have.

NICE picture of Kogio periotics in the 1st PDF, Jack

NEW, Chris. I was about to reply to Al Dente, and this was sitting from last night in my submit buffer.  :headscratch::headscratch:

 

5c47c07bab340_Floridakogiopsisteethinjaw.jpg.5988f445d8da93b403573482ad62fb29.jpg

Yep there are some good ones in there. In the other document I thought I'd see a nice orderly set of teeth for Kogiopsis floridana, but I guess not!! Still cool! 

Regards, Chris 

 

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Previously in this thread, I asked the question of whether Modern Sperm Whales have enamel. As my knowledge grows, I will keep this thread updated. Here is an answer:

Quote

 jstage.jst.go.jp
Comparative histology of tooth enamel in several toothed whales
Because of the existence of only a few papers on the histological observation of tooth enamel in whales, the enamel structures have not been well elucidated. The tooth enamel in seven species of toothed whales were, therefore, studied by scanning electron microscopy, polarizing microscopy and contact microradiography, and the structural characteristics among them were compared.
Enamel structure in each family was different from all the others. Physeter catodon (sperm whale) possessed tiny cap enamel at the tip of the maxillary teeth. The enamel was about 200μm in thickness and aprismatic. In Berardius bairdi (Baird's beaked whale) very thin and aprismatic enamel covered the tip of the mandibular teeth. The thickness of enamel was 3-5 μm corresponding to the thickness of ophidian or coelacanthine enamel. Stenella frontalis (bridled dolphin), Globicephala macrorhyncha (pilot whale) and Pontoporia blainvillei (La Plata River dolphin) possessed prismatic enamel, and prism pattern of enamel in these species revealed various types. The enamel of Neophocaena phocaenoides (finless black porpoise) was indistinct in prismatic structure of the whole layer.The enamel of Phocoenoides dalli (Dall's porpoise) was aprismatic and tubular and showed a low degree of mineralization by contact microradiography.
The results obtained in this study indicate that the thickness of enamel does not appear to be a factor differentiating it into prismatic or aprismatic enamel. Most probably a correlation exists between body size and degree of enamel development; the small sized species (dolphin and porpoise) possess well developed enamel while, the large sized species (sperm whale and beaked whale) possess poorly developed enamel.

I also discussed What is Ivory as it relates to Whales.  Here is a hint. I am beginning to believe that Ivory == Enamel and there are minimal amounts of either in extant whale teeth.

ProsqualodonEnamel.JPG.b3ec5d1b9c3ddd052f1539a0fa16aabf.JPG

 

Comments /views definitely appreciated,  Jack

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