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Jawless Creature Had the World's Sharpest Teeth

samzenpus posted more than 2 years ago | from the his-bite-is-worse-than-his-bark dept.

Science 53

ananyo writes "An extinct primitive marine vertebrate had the sharpest dental structures ever known — with tips just one-twentieth of the width of a human hair, but able to apply pressures that could compete easily with those from human jaws. The razor-sharp teeth belonged to conodonts, jawless vertebrates that evolved some 500 million years ago in the Precambrian eon and went extinct during the Triassic period, around 200 million years ago. The creatures roamed the planet for longer than any other vertebrate so far–– and despite their lack of jaws, they were the first creatures to evolve teeth (abstract)."

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SOUNDS LIKE A REPUBLICAN TO ME !! (-1, Troll)

Anonymous Coward | more than 2 years ago | (#39359187)

They are all jawless assholes !!

How accurate? (1)

multiben (1916126) | more than 2 years ago | (#39359199)

Is there any compensation that has to be applied to fossils which are over 200 million years old? Such as erosion etc?

Re:How accurate? (5, Informative)

Anonymous Coward | more than 2 years ago | (#39359671)

Not as much as you would think. Conodonts are composed of calcium phosphate -- the same stuff as our teeth. It's fairly durable mineral. They are usually extracted from rocks in almost unaltered state. Conodonts do get broken and worn like any other sediment particle, so sometimes they're a bit beaten up, but often they are nearly intact despite being fairly fragile-looking structures. Sometimes their surfaces even show wear from the time when the animal was alive (i.e. tooth wear). Growth lines and other structures are visible internally.

The rest of the animal -- the body -- is soft tissues, so that part rarely preserves and is flattened even when it is preserved, however, multiple specimens compressed in different orientations reveal the 3D structure. There are also slightly more robust structures around the eye sockets (sclerotic capsules).

Re:How accurate? (1)

Dahamma (304068) | more than 2 years ago | (#39359709)

Is there any compensation that has to be applied to fossils which are over 200 million years old?

No, I think their tooth patents are all expired...

Re:How accurate? (0)

Anonymous Coward | more than 2 years ago | (#39359953)

Pshh no I bet they didn't think of that, good thing you pointed that out they would have never known.

Re:How accurate? (-1, Flamebait)

multiben (1916126) | more than 2 years ago | (#39360415)

I wasn't pointing it out. I was asking because I don't know. Dickhead.

Re:How accurate? (0)

Anonymous Coward | more than 2 years ago | (#39370243)

YEAH, You tell that anonymous person on the internet. I bet he's hurt.

Really?

Dentist insight... (0)

Anonymous Coward | more than 2 years ago | (#39359209)

Well there is a reason they were extinct. Teeth that sharp would 1. Either dull down quickly (depends on how long it lived) 2. Be fragile enough to break after catching prey.

Re:Dentist insight... (0)

Anonymous Coward | more than 2 years ago | (#39359303)

They 'were' extinct? As far as we can tell, they still are extinct. You assume that they 1) didn't replace teeth as they wore out and 2) used their teeth to catch prey. For a dentist, you are amazingly obtuse.

Re:Dentist insight... (1)

flyneye (84093) | more than 2 years ago | (#39362419)

Just a blast of Nitrous in the morning with your coffee...

Re:Dentist insight... (1)

camperdave (969942) | more than 2 years ago | (#39359563)

Well there is a reason they were extinct. Teeth that sharp would 1. Either dull down quickly (depends on how long it lived) 2. Be fragile enough to break after catching prey.

Perhaps they were like rodent's teeth, constantly growing and softer on one side than the other, so that as it ate the tooth would sharpen itself and any breakages would be replaced.

Re:Dentist insight... (1)

Dahamma (304068) | more than 2 years ago | (#39359727)

Another dentist insight: dentists don't like to RTFA...

But super-sharp teeth can cause problems. “If you have sharp teeth they are more likely to break,” says Donoghue. To overcome this, the animals seem to have been able to re-sharpen and repair worn teeth throughout their lives — a quality that other vertebrates have failed to evolve.

Re:Dentist insight... (2)

skegg (666571) | more than 2 years ago | (#39362063)

I don't think you could call their design flawed: they roamed this planet for about 1/3 billion years.
From the summary:

The creatures roamed the planet for longer than any other vertebrate so far.

Re:Dentist insight... (1)

DaveWick79 (939388) | more than 2 years ago | (#39362397)

Because you can tell from a fossil how long they were around. And you can tell that an animal looks like an eel by a set of fossilized teeth.

I don't care how great of a scientist you are, you can't predict what an animal looked like from a set of teeth. Imagine the wild designs they would come up with for humans if all they had to go on was a tooth.

Re:Dentist insight... (1)

flirno (945854) | more than 2 years ago | (#39362911)

No prediction here.

What are believed to be conodonts have been found in legerstatte deposit which can preserve impressions of softer tissues.

https://en.wikipedia.org/wiki/Lagerst%C3%A4tte [wikipedia.org]

Re:Dentist insight... (1)

fiannaFailMan (702447) | more than 2 years ago | (#39367983)

Well there is a reason they were extinct. Teeth that sharp would 1. Either dull down quickly (depends on how long it lived) 2. Be fragile enough to break after catching prey.

Some species developed an ability to re-grow tooth material. Quoth TFA:

To overcome this, the animals seem to have been able to re-sharpen and repair worn teeth throughout their lives — a quality that other vertebrates have failed to evolve.

Sounds like this creature... (-1, Offtopic)

GmExtremacy (2579091) | more than 2 years ago | (#39359215)

Sounds like this creature... should have used Gamemaker!

Re:Sounds like this creature... (0)

Anonymous Coward | more than 2 years ago | (#39360899)

I don't get it

Re:Sounds like this creature... (1)

GmExtremacy (2579091) | more than 2 years ago | (#39360943)

Because you don't even understand life itself! Life itself is completely unknown to one such as you.

Wow! There are dark rumors about you circulating all over the grapevine. They were started by... Komen Bryce himself!

The rumor's text? "Anonymous Coward is misign a few gigabit on his puter... bai2u... >_>"

I know, I know. Your very soul has been shattered. You are a mere shell of what you once were. You're nothing. You can just turn to dust and die now!

Re:Sounds like this creature... (0)

Anonymous Coward | more than 2 years ago | (#39361353)

I still don't get it...

Here is the wikipedia article (4, Informative)

buchner.johannes (1139593) | more than 2 years ago | (#39359243)

of this eel-like creature [wikipedia.org] ... looks like we don't know much about them aside from their teeth?

Meteorites suck. I mean blow.

Re:Here is the wikipedia article (0)

Anonymous Coward | more than 2 years ago | (#39359285)

Awww man there's no artist's conception of it on the page, I have to read and use my imagination now. I'm so depressed now...

Re:Here is the wikipedia article (0)

Anonymous Coward | more than 2 years ago | (#39359949)

Meteorites suck. I mean blow.

And with the chompers these things had I'll bet they didn't do either.

Re:Here is the wikipedia article (2)

Randle_Revar (229304) | more than 2 years ago | (#39360001)

There is no particular reason to think the Triassic-Jurassic extinction was caused by an impact event.

Re:Here is the wikipedia article (0)

Anonymous Coward | more than 2 years ago | (#39365451)

There is no particular reason to think the Triassic-Jurassic extinction was caused by an impact event.

I guess that depends on your definition of particular, but there are reason to suspect (aka think) it happened. There's little evidence to support it, just as there's little evidence to support any alternative theory. It's quite an annoying little mystery, but calling people unreasonable for thinking about a theory isn't very nice.

Re:Here is the wikipedia article (1)

Randle_Revar (229304) | more than 2 years ago | (#39375883)

>There's little evidence to support it, just as there's little evidence to support any alternative theory

Exactly.

And I didn't say that OP was unreasonable.

Freaky Beasties (5, Interesting)

Sponge Bath (413667) | more than 2 years ago | (#39359259)

Here [le.ac.uk] are some speculative drawings of the creatures. Getting caught in a swarm of thrashing sharp dental structures would make a good horror film.

Re:Freaky Beasties (2)

ColdWetDog (752185) | more than 2 years ago | (#39359481)

"Heterochrony in cavusgnathid conodonts"

I love titles that I cannot begin to pronounce, much less understand.

Re:Freaky Beasties (0)

Anonymous Coward | more than 2 years ago | (#39359569)

Here [le.ac.uk] are some speculative drawings of the creatures. Getting caught in a swarm of thrashing sharp dental structures would make a good horror film.

Yeah, but "Jawless" doesn't make for the most intimidating title.

Re:Freaky Beasties (2)

wiedzmin (1269816) | more than 2 years ago | (#39359829)

I disagree. I would watch a movie that said Jawless in red bloody letters and had one of those things on the poster.

Re:Freaky Beasties (0)

Anonymous Coward | more than 2 years ago | (#39359767)

Thankfully reconstructions of conodonts suggest most of them were only 10 or 20cm long. So, it would be a bit like being attacked by tiny, eel-like toothy leeches.

But, hey, scale them up to a few metres long and they'd be damn scary.

Re:Freaky Beasties (1)

TheLink (130905) | more than 2 years ago | (#39361391)

Being attacked by a hundred 20cm long leeches with very sharp teeth would be scary. Horror movie material even.

Re:Freaky Beasties (1)

Sneeka2 (782894) | more than 2 years ago | (#39361457)

Getting caught in a swarm of thrashing sharp dental structures would make a good horror film.

Yup, coming to a theater near you April 19 [imdb.com] .

Re:Freaky Beasties (0)

Anonymous Coward | more than 2 years ago | (#39367383)

Some close modern analogues for your viewing pleasure:
Sea Lampreys [youtube.com]
Hagfish [youtube.com]

They still exist today (1)

retroworks (652802) | more than 2 years ago | (#39359333)

Having evolved to chew through solid rock... They bored into the earth, and have evolved to make sustainable life energy in the heat below the earth's mantle... What's that noise?... Come closer to the campfire.

Re:They still exist today (1)

BenJCarter (902199) | more than 2 years ago | (#39360935)

Having evolved to chew through solid rock... They bored into the earth, and have evolved to make sustainable life energy in the heat below the earth's mantle... What's that noise?... Come closer to the campfire.

If they are smart, they will evolve into goa'uld [wikipedia.org] , and be preserved forever on Netflix [netflix.com] ...

evolved some 500 million...extinct 200 million yea (0)

Anonymous Coward | more than 2 years ago | (#39359379)

You know, 300 million years is a pretty good run. *golf clap*

Just when you thought... (4, Funny)

PCM2 (4486) | more than 2 years ago | (#39359523)

Just when you thought it was safe to go back in the water ... JAWLESS!

Jawless: Correlation or Causation? (0)

Anonymous Coward | more than 2 years ago | (#39359545)

Can one of the /. editors ask Ebert if his teeth have gotten any sharper?

Hagfish (2)

pauljlucas (529435) | more than 2 years ago | (#39359681)

Aren't these [wikipedia.org] living creatures related?

Re:Hagfish (3, Interesting)

Randle_Revar (229304) | more than 2 years ago | (#39360127)

Everything is related, it is a question of how closely. Seems some taxonomies put them near the hagfish class and the lamprey class, however a 2010 paper argues they are not Vertebrata at all, or even Craniata.

Re:Hagfish (1)

vtcodger (957785) | more than 2 years ago | (#39362865)

Aren't hagfish (technically Agnatha) related? Yes, but probably not too closely? They are about as old. But the fossil information on early vertebrates and similar critters is very sparse. It's hard to tell all that much about them. For example, there is a phylum of critters called Chaetognaths whose fossils somewhat resemble both fish and conodonts. They have eyes, fins, teeth. But unlike the conodonts, they survived until the present allowing biologists to determine that internally, the chaetognats don't look even remotely like fish. For example Chaetognaths have neither a respiratory system nor a circulatory system. Based only on fossils, the Chatognatha would probably incorrectly be thought to be closely related to fish and conodont.s The hypothecated resemblence of conodonts to fish may be equally imaginary.

Re:Hagfish (1)

oldmac31310 (1845668) | more than 2 years ago | (#39366101)

Fascinating. Thanks for that link.

Author doesn't understand pressure... (0)

Karganeth (1017580) | more than 2 years ago | (#39360279)

with tips just one-twentieth of the width of a human hair, but able to apply pressures that could compete easily with those from human jaws

The size of the surface area has no bearing on the amount of pressure that can be applied because pressure is force per unit area.

Re:Author doesn't understand pressure... (1)

priceslasher (2102064) | more than 2 years ago | (#39360809)

if pressure is force per unit area then it sounds like area and pressure are related - the smaller area for the same force will have higher pressure because force divided by a smaller value will continue to increase, right?

Re:Author doesn't understand pressure... (1)

voidphoenix (710468) | more than 2 years ago | (#39361921)

The size of the surface area has no bearing on the amount of pressure that can be applied because pressure is force per unit area.

Try again. Try harder.

And yet ... (0)

Anonymous Coward | more than 2 years ago | (#39360717)

""An extinct primitive marine vertebrate had the sharpest dental structures ever known "

It still couldn't chew my wife's meat loaf.

Useful fossils for biostratigraphic dating (0)

Anonymous Coward | more than 2 years ago | (#39361299)

Conodonts are very usefull for dating rocks, i use to work for the Maquarie University Center of Ecostratigraphy and Palaeobiology where we would dissolve tons (literally) of limestone with acetic acid to study these and other fossils.

Re:Useful fossils for biostratigraphic dating (1)

flirno (945854) | more than 2 years ago | (#39362931)

Yep. The oil industry use them all the time.

Article = fail? (0)

Anonymous Coward | more than 2 years ago | (#39363677)

Seriously, the article has some major fuck-ups:
"finite-element analysis — a method commonly applied to model the effects of physical forces on aeroplanes" ... and about everytwhere else FEA/FEM is the standard method for simulating anything where you have a mesh :D
"To overcome this, the animals seem to have been able to re-sharpen and repair worn teeth throughout their lives — a quality that other vertebrates have failed to evolve" ... rodents do exactly the same, the way their teeth close makes them grind against each other, creating a continuously sharp edge (sorry if I described that badly, EN is not my native language)

Roger Ebert (1)

chinton (151403) | more than 2 years ago | (#39364059)

Is jawless and has pretty sharp (figurative) teeth.

Obvious (1)

robi5 (1261542) | more than 2 years ago | (#39364583)

Given that it had no jawbone, it only makes sense that the teeth be sharp to still "get thru the point".

Chicken or .... (0)

Anonymous Coward | more than 2 years ago | (#39387071)

Guess we now know the answer to question of what came first, the teeth or the mouth?

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