Announcement

Collapse

Natural Science 301 Guidelines

This is an open forum area for all members for discussions on all issues of science and origins. This area will and does get volatile at times, but we ask that it be kept to a dull roar, and moderators will intervene to keep the peace if necessary. This means obvious trolling and flaming that becomes a problem will be dealt with, and you might find yourself in the doghouse.

As usual, Tweb rules apply. If you haven't read them now would be a good time.

Forum Rules: Here
See more
See less

Fossil of 'squid' eating a crustacean with the former having just been bit by a shark

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Fossil of 'squid' eating a crustacean with the former having just been bit by a shark

    I love these sort of fossils.

    An amateur collector discovered the 180 million year old (Early Jurassic) remains in a quarry near Stuttgart in southwestern Germany back in 1970, which only recently have been analyzed. What they found was a squid-like cephalopod known as a belemnite (Passaloteuthis laevigata) was in the process of devouring a crustacean of the genus Proeryon (it had a broad and flat lobster-like body and long, gracile claws), when it was interrupted by another marine beast, likely a shark, that bit into the belemnite's squishy side, tearing out a large portion and killing it. This creating the "fish-eat-belemnite-eat-crustacean world" captured in the fossil.

    Whatever it was that took a bite out of the belemnite, the predator didn't stay around to finish its meal, probably because they have tough rostra -- beaks that are hard, pointed and difficult to digest. In fact, according to the researchers, it's possible that it purposefully targeted the belemnite's "soft parts, which were poorly protected" having learned to avoid the pointy hard tip.

    The belemnite specimen was remarkably well preserved condition, whereas the crustacean was in much poorer condition with the researchers concluding that it was in the process of molting.


    Source: Fantastical Jurassic Fossil Shows Crustacean Eaten by Squid Eaten by Shark


    Sometime in the early Jurassic, an ancient squid-like creature speared a yummy lobster-like crustacean with its many hooked tentacles. Just as it began to dig into its meal, the eater became the eaten.

    A much larger predator swooped in, tore a chunk out of the squid's soft middle and dashed off, leaving the leftovers of this three-way feeding fest sinking slowly to the bottom.

    Roughly 180 million years later, the fossilized scene has been discovered in a quarry in Germany, and after close analysis, paleontologists now think they've figured out who was at the top of the food chain.

    According to experts, the extinct squid-like cephalopod, known as a belemnite, was most probably killed by an ancient crocodile, shark, or other large predatory fish.

    Whatever it was, the predator didn't stick around to finish its meal, likely because cephalopods have tough rostra - beaks that are hard, pointed and difficult to digest.

    This means the hunter probably wasn't an ichthyosaur, even though fossils of these extinct marine reptiles suggest they were particularly skilled at picking around the hard areas of belemnites. Their stomach contents only show the mega-hooks found on belemnite tentacles and no other hard structures.

    Fossilized stomachs of marine crocodiles and predatory fish, on the other hand, suggest these creatures gobbled everything down, swallowing both the mega-hooks and the hard beaks of squid.

    Yet eating the whole squid isn't necessarily a good thing. A fossilized shark, also found in Germany from the Jurassic, was found with a whole pile of belemnite beaks in its stomach, and experts say these hard structures likely caused the shark's death. The diagram below shows the extreme blockage they created in the creature's stomach.

    7417cfe1-e79e-42ac-8ee0-aa12e1a038a9.jpg
    The Early Jurassic shark, Hybodus haufanus, with its stomach clogged by belemnite rostra.



    After some uncomfortable experiences, the authors suggest ancient sharks and crocs in the Jurassic learned to go after only the soft parts of their squid prey, choosing to drop the fins, rostrum, and mantle.

    In the current fossil, for example, the belemnite has retained its rostrum and arms, but everything soft in between is gone.

    fossil-found-of-ancien-1-2.jpg
    Preserved arm crown of belemnite and remains of its prey.


    "Remarkably, most of the belemnite soft parts between the arm crown and the calcitic rostrum are missing," the authors note.

    "We suggest that this represents remains of a meal of a vertebrate predator, possibly of the Early Jurassic shark Hybodus hauffianus. This is remarkable, because it informs about the behavior of a cephalopod and a vertebrate predator."

    A possible scenario explaining the fossilized remains has been illustrated below, showing a squid-like creature chewing on a crustacean while, in turn, a shark chews on it.




    The team have classified their discovery as a 'leftover fall', which is sort of like a whale fall, except this one is caused by an ocean predator dropping all or part of its meal.

    Once the uneaten prey sinks to the bottom, fewer scavengers and weaker currents make fossilization more likely.

    The result is a 'pabulite', a term which the authors of the new study have coined to describe a fossilized leftover fall. It's a combination of the Latin word for food, pabulum, and the Greek word for stone, lithos.

    Pabulites have been discovered numerous times over the years, and while solitary heads, fins and tails of ancient creatures might seem less valuable then a complete fossil, these incomplete remains can help us form a unique picture of the Jurassic food web.


    Source

    © Copyright Original Source



    The entire paper, Fossilized leftover falls as sources of palaeoecological data: a ‘pabulite’ comprising a crustacean, a belemnite and a vertebrate from the Early Jurassic Posidonia Shale can be found at the hyperlink provided, although here is the abstract from it:

    Abstract

    Especially in Lagerstätten with exceptionally preserved fossils, we can sometimes recognize fossilized remains of meals of animals. We suggest the term leftover fall for the event and the term pabulite for the fossilized meal when it never entered the digestive tract (difference to regurgitalites). Usually, pabulites are incomplete organismal remains and show traces of the predation. Pabulites have a great potential to inform about predation as well as anatomical detail, which is invisible otherwise. Here, we document a pabulite comprising the belemnite Passaloteuthis laevigata from the Toarcian of the Holzmaden region. Most of its soft parts are missing while the arm crown is one of the best preserved that is known. Its arms embrace an exuvia of a crustacean. We suggest that the belemnite represents the remnant of the food of a predatory fish such as the shark Hybodus.



    I'm always still in trouble again

    "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
    "Of course, human life begins at fertilization that’s not the argument." --Tassman

Related Threads

Collapse

Topics Statistics Last Post
Started by rogue06, 06-17-2021, 06:47 PM
2 responses
18 views
0 likes
Last Post rogue06
by rogue06
 
Started by rogue06, 06-17-2021, 08:37 AM
21 responses
80 views
1 like
Last Post rogue06
by rogue06
 
Started by lee_merrill, 06-16-2021, 05:09 PM
17 responses
75 views
0 likes
Last Post lee_merrill  
Started by rogue06, 06-16-2021, 07:53 AM
7 responses
34 views
0 likes
Last Post rogue06
by rogue06
 
Started by shunyadragon, 06-15-2021, 08:37 PM
1 response
20 views
1 like
Last Post rogue06
by rogue06
 
Working...
X