South African shark tooth ID

[britishcanuk]

I just got this interesting white shark tooth, it was found somewhere on the west coast of South Africa. It has beautiful wavy edges, and looks to represent an early example of either escheri or hubbelli/carcharias. Id love to hear some thoughts on what lineage this tooth would be from given its location. Also, what species would you assign it to?

 

cheers!

[Macrophyseter]

Kinda looks like a mako to me.

[britishcanuk]

It is certainly from the hastalis lineage (white shark, not mako), but what I'm wondering is which way its descendants went, escheri or hubbelli, given the South African locale. I think escheri, but was hoping to get some feedback from others.

[ynot]

I would call it a transitional white shark. The serrations are faint and variable which is inconsistent with a great white, which has consistent fine serrations.

[Miocene_Mason]

It gets confusing with these ones, the taxonomy is not completely understood, and intermediate forms exist, making it hard to put an exact label on them.

[Fossil-Hound]

There is an open debate on the transition of Great White Sharks or should I say evolution. Great White's are not direct decedents of Megalodon but rather a transitionary Mako shark. Keep in mind that this topic is grey as the shark existed millions of years ago. There are a lot of gaps and unknowns but what we know is that Mako teeth, or teeth that look like Mako referred to as Isurus Hastalis or Carcharodon Hastalis show up in the fossil record long before Great White Shark teeth as we know them today with very punctuated serrations. Check out this entry from a C. hastalis I recovered a few months ago:

 

Also read up on this entry:

 

Mako and Great Whites are very closely related and most likely came from the same species which would have looked more like a Mako than a Great White but both come from the order of Lamniformes and that's why I. hastalis and C. hastalis may be used interchangeably.

 

Here is a tooth entry of a Great White. Notice the puncuated serrations yet similar structure to a C. hastalis:

 

What you have is definitely a C. hastalis.

[doushantuo]

In paleontology most species are chronospecies,with an unknown biological meaming.

A while back i posted this:

 

 

 

 

[doushantuo]

Variability,Recent,heterodont dentition:

litvinpiscesela!!!N2705.pdf

An examination of more than a hundred tooth rows 

 

[britishcanuk]

I was just wondering if this was an early escheri or early hubbelli. I suspect escheri based on its Atlantic origins, but wanted other opinions.

 

cheers!

[Miocene_Mason]

The whole thing, chronospecies in general, is confusing to me. I took a course on Paleoanthropology (human evolution) once, and it's the same thing, a everchanging lineage without any punctuated equilibrium to speak of (well that's not necessarily true). I want to believe megs are the great white direct antecessor, but I accept that it's probably C. Hastilis. Eventually you learn species are a designation by humans, not a law nature abides by.

[Fossil-Hound]

3 minutes ago, doushantuo said:

In paleontology most species are chronospecies,with an unknown biological meaming.

A while back i posted this:

 

 

 

 

 

Excellent documentation @doushantuo Here's an interesting National Geographic entry:

 

http://phenomena.nationalgeographic.com/2012/11/15/great-white-shark-ancestry-swims-into-focus/

 

On a side note you'll find transitional species such as C. Augunstine. Paleontologists theorize these were the transitional sharks evolving from O. obliquus. Later these became C. chubutensis and possibly C. megalodon though that's not as likely because C. chubutensis and C. megalodon closely coexisted. The emergence of C. megalodon as a super predator and larger than any the ocean has ever seen is a bit of a mystery. What's even more interesting is these super predators seem to have vanished a couple of million years ago whereas the C. carcharias outlasted them. Keep in mind C. carcharias came onto the stage during the end of the reign of the super sharks. Could it be an evolved form of C. chubutensis?

[ynot]

@Al Dente should be able to answer the question.

6 minutes ago, britishcanuk said:

I was just wondering if this was an early escheri or early hubbelli. I suspect escheri based on its Atlantic origins, but wanted other opinions.

 

cheers!

 

 

 

Just to get back on subject.

[Fossil-Hound]

1 minute ago, WhodamanHD said:

The whole thing, chronospecies in general, is confusing to me. I took a course on Paleoanthropology (human evolution) once, and it's the same thing, a everchanging lineage without any punctuated equilibrium to speak of (well that's not necessarily true). I want to believe megs are the great white direct antecessor, but I accept that it's probably C. Hastilis. Eventually you learn species are a designation by humans, not a law nature abides by.

 

Megalodon evolved from O. obliquus or so there seems to be more supporting evidence. See my latest post. This is a very interesting topic because O. obliquus was of the order Lamniformes as well supposedly the great ancestral shark.

[Miocene_Mason]

5 minutes ago, Fossil-Hound said:

 

Excellent documentation @doushantuo Here's an interesting National Geographic entry:

 

http://phenomena.nationalgeographic.com/2012/11/15/great-white-shark-ancestry-swims-into-focus/

 

On a side note you'll find transitional species such as C. Augunstine. Paleontologists theorize these were the transitional sharks evolving from O. obliquus. Later these became C. chubutensis and possibly C. megalodon though that's not as likely because C. chubutensis and C. megalodon closely coexisted. The emergence of C. megalodon as a super predator and larger than any the ocean has ever seen is a bit of a mystery. What's even more interesting is these super predators seem to have vanished a couple of million years ago whereas the C. carcharias outlasted them. Keep in mind C. carcharias came onto the stage during the end of the reign of the super sharks. Could it be an evolved form of C. chubutensis?

Im still as typical off subject. C. Carcharius is a good deal smaller than megalodon and chubutensis, the big ones died out I'm guessing because off a cooler climate, which not only limited its range but shrunk the amount of marine mammals (many sirenians and cetaceans died out and they were probably their main food source) all three (angustidens, chubutensis, megaladon( coexisted at one time btw.

 

3 minutes ago, Fossil-Hound said:

 

Megalodon evolved from O. obliquus or so there seems to be more supporting evidence. See my latest post. This is a very interesting topic because O. obliquus was of the order Lamniformes as well supposedly the great ancestral shark.

Great, now otodus is in the mix I gotta change my family tree now! now I gotta carry the one and add the 3.......

Forgot to add, great white lived because it needed less food to survive.

[Fossil-Hound]

7 minutes ago, WhodamanHD said:

Im still as typical off subject. C. Carcharius is a good deal smaller than megalodon and chubutensis, the big ones died out I'm guessing because off a cooler climate, which not only limited its range but shrunk the amount of marine mammals (many sirenians and cetaceans died out and they were probably their main food source) all three (angustidens, chubutensis, megaladon( coexisted at one time btw.

 

Great, now otodus is in the mix I gotta change my family tree now! now I gotta carry the one and add the 3.......

Forgot to add, great white lived because it needed less food to survive.

 

On the contrary Great White sharks need a lot of food and all these species evolved over time. I'm also aware of C. angustidens, C. chubutensis, and C. megalodon coexisting however there is some theories on how C. chubutensis evolved through the line of O. obliquus and C. angustidens. This topic, just like the waters in which they swam in is a bit murky however it is very interesting. A colleague of mine claimed that these sharks were all warm blooded and whales evolved fled to the polar caps to avoid these mega predators thus avoiding predation and starving them out. That's an interesting claim with little supporting evidence but could be valid.

[doushantuo]

cionerns_vol10-2_175-184.pdf

Can't post an outtake: but the PDF is Cione on Carcharadon biogeography,past & present(with a slight emphasis on South America)

[Miocene_Mason]

10 minutes ago, Fossil-Hound said:

 

On the contrary Great White sharks need a lot of food and all these species evolved over time. I'm also aware of C. angustidens, C. chubutensis, and C. megalodon coexisting however there is some theories on how C. chubutensis evolved through the line of O. obliquus and C. angustidens. This topic, just like the waters in which they swam in is a bit murky however it is very interesting. A colleague of mine claimed that these sharks were all warm blooded and whales evolved fled to the polar caps to avoid these mega predators thus avoiding predation and starving them out. That's an interesting claim with little supporting evidence but could be valid.

I dare say a sixty foot megalodon may require a bit more food than a great white, small in comparison. The ice cap idea is interesting, I guess only statistical analysis of amounts of finds as you progress northwards would be evidence to prove it though.

[Fossil-Hound]

3 minutes ago, WhodamanHD said:

I dare say a sixty foot megalodon may require a bit more food than a great white, small in comparison. The ice cap idea is interesting, I guess only statistical analysis of amounts of finds as you progress northwards would be evidence to prove it though.

 

Great Whites need a lot of food. They are warm blooded and use the food to warm their blood allowing them to dive considerable depths. They must eat a lot to sustain their body weight and functions especially in cooler waters. I can't imagine how much food a fully grown C. megalodon must have ate. Another friend of mine said a fully grown Megalodon wouldn't pose as a threat to humans because we would appear to be minnows to them.

[doushantuo]

i can recommend this one:

Can't post it,it's 57 Mb

[Fossil-Hound]

Some more interesting theories on C. megalodon, albeit off topic the O. obliquus was of the order Laminformes the same that the Great White yields from (I don't completely agree with these theories but they are interesting):

 

 

 

 

[doushantuo]

diedr

[Al Dente]

4 hours ago, britishcanuk said:

I was just wondering if this was an early escheri or early hubbelli. I suspect escheri based on its Atlantic origins, but wanted other opinions.

 

cheers!

I agree with britishcanuk. I would guess it is most likely escheri. Too bad we don't know the age.

[doushantuo]

agreed

 

[SailingAlongToo]

7 hours ago, Fossil-Hound said:

 

Great Whites need a lot of food. They are warm blooded and use the food to warm their blood allowing them to dive considerable depths. They must eat a lot to sustain their body weight and functions especially in cooler waters. I can't imagine how much food a fully grown C. megalodon must have ate. Another friend of mine said a fully grown Megalodon wouldn't pose as a threat to humans because we would appear to be minnows to them.

 

Sardines appear to be minnows to me but I sure eat them. Especially with some hot sauce or spicy mustard. Just saying......... 

[Shellseeker]

2 hours ago, SailingAlongToo said:

 

Sardines appear to be minnows to me but I sure eat them. Especially with some hot sauce or spicy mustard. Just saying......... 

Yes,

We have had a week of heavy rains which have created backyard ponds, shortly thereafter filled with tree frogs,  offspring and various water bugs..  Today 50 dinosaur descendants *herons, ibis, egrets* have arrived to gobble up these appetizers that are 50-100 times smaller.

Were I a human swimming with Megs, I would likely lack confidence depending on their preference for larger prey to keep me in 1 piece.