Jump to content

Sonic0627

Recommended Posts

I’m pretty sure the white tooth is a fossilized mako and I think the dark is a juvenile Megalodon or great white. Pretty sure it’s a meg what do you guys think?

6B2F18A8-A0FB-4753-AB66-454AE294686A.jpeg

Link to comment
Share on other sites

Yessir, you are right! :)

 

White tooth is from a Carcharodon hastalis and dark is from a Carcharocles megalodon. If it were to be a great white shark tooth, it would look more like the C. hastalis tooth but with serrations.

If you're a fossil nut from Palos Verdes, San Pedro, Redondo Beach, or Torrance, feel free to shoot me a PM!

 

 

Mosasaurus_hoffmannii_skull_schematic.png

Link to comment
Share on other sites

I agree. Carcharodon hastalis and Otodus megalodon. Used to be Carcharocles. 

Bulldozers and dirt Bulldozers and dirt
behind the trailer, my desert
Them red clay piles are heaven on earth
I get my rocks off, bulldozers and dirt

Patterson Hood; Drive-By Truckers

 

image.png.0c956e87cee523facebb6947cb34e842.png May 2016  MOTM.png.61350469b02f439fd4d5d77c2c69da85.png.a47e14d65deb3f8b242019b3a81d8160.png.b42a25e3438348310ba19ce6852f50c1.png May 2012 IPFOTM5.png.fb4f2a268e315c58c5980ed865b39e1f.png.1721b8912c45105152ac70b0ae8303c3.png.2b6263683ee32421d97e7fa481bd418a.pngAug 2013, May 2016, Apr 2020 VFOTM.png.f1b09c78bf88298b009b0da14ef44cf0.png.af5065d0585e85f4accd8b291bf0cc2e.png.72a83362710033c9bdc8510be7454b66.png.9171036128e7f95de57b6a0f03c491da.png Oct 2022

Link to comment
Share on other sites

12 minutes ago, Macrophyseter said:

Yessir, you are right! :)

 

White tooth is from a Carcharodon hastalis and dark is from a Carcharocles megalodon. If it were to be a great white shark tooth, it would look more like the C. hastalis tooth but with serrations.

Wow I’m so glad I got this right. My kiddo will be so excited for both of these and thank you for replying with the scientific names so I can tell him about them! 

Link to comment
Share on other sites

What are our sizes on these "bad boys"?

Always a good practice to include a ruler in pictures so we have an idea of scale.

 

 

Link to comment
Share on other sites

1 hour ago, sixgill pete said:

Used to be Carcharocles. 

Gonna start a fight with that!

 

Its a debate whether it should be Carcharocles or Otodus, I personally lean Otodus but many researchers think otherwise. However, many lean otodus. Just to confuse everyone some even put Megaselachus for some reason. 

“...whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been and are being evolved.” ~ Charles Darwin

Happy hunting,

Mason

Link to comment
Share on other sites

28 minutes ago, caldigger said:

What are our sizes on these "bad boys"?

Always a good practice to include a ruler in pictures so we have an idea of scale.

 

 

1AE71BD0-810F-473C-8179-850C7EAFE530.jpeg

Link to comment
Share on other sites

1 hour ago, WhodamanHD said:

Gonna start a fight with that!

 

Its a debate whether it should be Carcharocles or Otodus, I personally lean Otodus but many researchers think otherwise. However, many lean otodus. Just to confuse everyone some even put Megaselachus for some reason. 

OK, on the count of three...rocks, paper, scissors!

 

Its a nice looking  _?_ hastalis by whatever you want to call it! ;)

 

 

Link to comment
Share on other sites

3 minutes ago, caldigger said:

OK, on the count of three...rocks, paper, scissors!

 

Its a nice looking  _?_ hastalis by whatever you want to call it!

:ighappy:

Link to comment
Share on other sites

1 hour ago, WhodamanHD said:

Gonna start a fight with that!

 

Its a debate whether it should be Carcharocles or Otodus, I personally lean Otodus but many researchers think otherwise. However, many lean otodus. Just to confuse everyone some even put Megaselachus for some reason. 

 

Adding to Whodaman,

 

True, as of now as far as I know, three genera are currently used for megalodon- CarcharoclesOtodus, and Megaselachus. At this point, this is a -phyly debate that has been raging since Carcharodon megalodon. As far as I know, Megaselachus was supposed to be a genus for megalodon and chub only to differentiate from other Carcharocles species (true cusps vs no full cusps) for those who disagree with the current popular evolutionary lineage, it's complicated. There are many, many alternative lineages for megalodon. In fact, I'll just pull up a strange proposal by Diedrich (2013):

image.thumb.png.b88e459415d2c13740f068837e2802f1.png

 

As for Carcharocles vs Otodus, this debate has been a thing since decades, but has recently grown in popularity after Shimada (2017)'s paper assessing that Otodus can only become monophyletic if it absorbs the Carcharocles genera. To be exact, popularity on this could be because Shimada's paper became heavily reported on by news.

 

The consensus over whether or not paraphyly within a genera is okay or not is still debated and divided over scientists across all biology. Proponents of anti-paraphyly argue that such degrades consistency by grouping based on phylogeny rather than classification, while "paraphyly is okay" proponents argue that it can be necessary in order to accurately group certain taxons. In the realm of shark-paleontology, the consensus between Carcharocles or Otodus is also divided. Shimada, Cappetta and others use Otodus megalodon while Siverson, Kent and others use Carcharocles megalodonMegaselachus megalodon is also still used by some paleontologists, but it is not well recognized outside the scientific community.

 

I personally side with Carcharocles although it not a popular opinion with paleo-amateurs, but as long as the debate over paraphylys within genera rage on, both Carcharocles and Otodus are still very possible valid taxons and neither should be called "former" or "outdated" until this debate is officially settled.

 

Here is an except of Shimada (2017) regarding Otodus paraphyly:

image.thumb.png.2e8ac8ee93f758888256e2f65b690009.pngimage.thumb.png.37b93e411fb499ebb5a7a173b097db65.png

 

 

 

 

If you're a fossil nut from Palos Verdes, San Pedro, Redondo Beach, or Torrance, feel free to shoot me a PM!

 

 

Mosasaurus_hoffmannii_skull_schematic.png

Link to comment
Share on other sites

13 hours ago, caldigger said:

Its a nice looking  _?_ hastalis by whatever you want to call it! ;)

Cosmopolitodus or Carcharodon. You too can have your own scientific views on things, if you disagree with the current understandings of the taxon, why not propose the scientific name Kalopachymegaloenmegalodonodontmachomaiotoduscarcharoclesdemetisphrontihotibaldeodontkalos hastalis:P (The name is not gibberish, it has a meaning!)

If you're a fossil nut from Palos Verdes, San Pedro, Redondo Beach, or Torrance, feel free to shoot me a PM!

 

 

Mosasaurus_hoffmannii_skull_schematic.png

Link to comment
Share on other sites

10 hours ago, Macrophyseter said:

 

Adding to Whodaman,

 

True, as of now as far as I know, three genera are currently used for megalodon- CarcharoclesOtodus, and Megaselachus. At this point, this is a -phyly debate that has been raging since Carcharodon megalodon. As far as I know, Megaselachus was supposed to be a genus for megalodon and chub only to differentiate from other Carcharocles species (true cusps vs no full cusps) for those who disagree with the current popular evolutionary lineage, it's complicated. There are many, many alternative lineages for megalodon. In fact, I'll just pull up a strange proposal by Diedrich (2013):

image.thumb.png.b88e459415d2c13740f068837e2802f1.png

 

As for Carcharocles vs Otodus, this debate has been a thing since decades, but has recently grown in popularity after Shimada (2017)'s paper assessing that Otodus can only become monophyletic if it absorbs the Carcharocles genera. To be exact, popularity on this could be because Shimada's paper became heavily reported on by news.

 

The consensus over whether or not paraphyly within a genera is okay or not is still debated and divided over scientists across all biology. Proponents of anti-paraphyly argue that such degrades consistency by grouping based on phylogeny rather than classification, while "paraphyly is okay" proponents argue that it can be necessary in order to accurately group certain taxons. In the realm of shark-paleontology, the consensus between Carcharocles or Otodus is also divided. Shimada, Cappetta and others use Otodus megalodon while Siverson, Kent and others use Carcharocles megalodonMegaselachus megalodon is also still used by some paleontologists, but it is not well recognized outside the scientific community.

 

I personally side with Carcharocles although it not a popular opinion with paleo-amateurs, but as long as the debate over paraphylys within genera rage on, both Carcharocles and Otodus are still very possible valid taxons and neither should be called "former" or "outdated" until this debate is officially settled.

 

Here is an except of Shimada (2017) regarding Otodus paraphyly:

image.thumb.png.2e8ac8ee93f758888256e2f65b690009.pngimage.thumb.png.37b93e411fb499ebb5a7a173b097db65.png

 

 

 

 

 

There have been a good number of shark species name controversies and name changes over the years.  That is why I don't label the shark teeth with name labels in my collection.  I got tired of changing name labels.

 

If you haven't picked a side in a name controversy you can use aka (also known as).  As example:  Carcharodon hastalis aka Isurus hastalis or Otodus megalodon aka Carcharocles megalodon.

 

There really aren't universal standards that govern when feature differences are sufficient enough to name a new genus or a new species.  Some researchers are splitters who name a new species on minor feature differences (what I consider minor) and seem to want to describe as many genera and species as possible.   For example, is the appearance of serrations enough of a feature change to change a species name or even a genus name?  Some researchers, who I call combiners, accept a good bit of feature variation before changing a genus or species name.  The name changes that I agree with relate to new and additional data discovered on shark lineage.  That is why I support Carcharodon over Isurus for hastalis.

 

I study extant shark jaws and teeth.  I see a good deal of tooth feature variation within a good number of extant shark species and sometimes even within an individual shark jaw.  So I'm definitely a combiner and not a splitter.

 

Marco Sr.

"Any day that you can fossil hunt is a great day."

My family fossil website     Some Of My Shark, Ray, Fish And Other Micros     My Extant Shark Jaw Collection

image.png.9a941d70fb26446297dbc9dae7bae7ed.png image.png.41c8380882dac648c6131b5bc1377249.png

Link to comment
Share on other sites

5 hours ago, MarcoSr said:

who I call combiners,

AKA lumpers.

 

I like the way it was put by elasmo.com.

“How many slices can you get out of a loaf of bread?”

Natures given you our loaf, scientists bicker on how to slice it. Species ae an artificial construct.

What is a species? 3 ways to answer that, the genetic species concept, the biological species concept, and the Morphological species concept. All three are flawed, but by far the most flawed is the morphological species concept which just so happens to be the one we have to use on fossils. Not to mention, most of the time we are working with isolated teeth. Imagine if you had to classify all hominins based off their teeth alone, you’d start to get into some real problems. We fight even with full skeletons! This means there really is no definite answer, only one that a majority will choose to accept.

“...whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been and are being evolved.” ~ Charles Darwin

Happy hunting,

Mason

Link to comment
Share on other sites

15 hours ago, WhodamanHD said:

AKA lumpers.

 

I like the way it was put by elasmo.com.

“How many slices can you get out of a loaf of bread?”

Natures given you our loaf, scientists bicker on how to slice it. Species ae an artificial construct.

What is a species? 3 ways to answer that, the genetic species concept, the biological species concept, and the Morphological species concept. All three are flawed, but by far the most flawed is the morphological species concept which just so happens to be the one we have to use on fossils. Not to mention, most of the time we are working with isolated teeth. Imagine if you had to classify all hominins based off their teeth alone, you’d start to get into some real problems. We fight even with full skeletons! This means there really is no definite answer, only one that a majority will choose to accept.

 

There are a number of DNA testing projects being conducted on sharks.  Currently it is hard to get data from these projects.  I've only seen a couple of rudimentary papers.  As the results of these projects go mainstream, you will see more naming controversies beginning with extant species.

 

Marco Sr.

"Any day that you can fossil hunt is a great day."

My family fossil website     Some Of My Shark, Ray, Fish And Other Micros     My Extant Shark Jaw Collection

image.png.9a941d70fb26446297dbc9dae7bae7ed.png image.png.41c8380882dac648c6131b5bc1377249.png

Link to comment
Share on other sites

3 hours ago, MarcoSr said:

 

There are a number of DNA testing projects being conducted on sharks.  Currently it is hard to get data from these projects.  I've only seen a couple of rudimentary papers.  As the results of these projects go mainstream, you will see more naming controversies beginning with extant species.

 

Marco Sr.

Yeah, it’s already sent shockwaves through other extant families. Things can look exactly the same but be genetically worlds apart. The gray tree frog and copes gray tree frog for example.

 

Edit: think about the implications of this in the world of paleontology, morphology doesn’t cover these changes.

“...whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been and are being evolved.” ~ Charles Darwin

Happy hunting,

Mason

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...