A new analysis of long-lost fossils found that the vampire squid has been lurking in the dark corners of the ocean for 30 million years.
Modern vampire squid (Hell vampire) Can reproduce in hypoxic deep sea water, which is different from many other squids that require shallow habitats on the continental shelf.
However, few fossil ancestors among the vampire squids can survive today, so scientists are not sure when these elusive cephalopods will evolve to survive with little oxygen.
The new fossil analysis helps fill the 1
The co-author of the study, paleontologist Martin Košťák of Charles University in Prague, said that these squids may have evolved adaptability to hypoxic water during the Jurassic period.
Košťák wrote in an email to Live Science: “Life at a stable low oxygen level brings evolutionary advantages-low predation pressure and less competition.
Related: Photos of Hell Vampire Squid
Rediscovered fossils
When Košťák and his colleagues were looking for fossils of cuttlefish ancestors, they found the long-lost fossil in the collection of the Hungarian Museum of Natural History in 2019. The fossil was originally discovered in 1942 by Miklós Kretzoi, a Hungarian paleontologist who identified it as a squid about 30 million years ago and named it squid. Hungarian dead bacteria. However, later researchers believe that this is the ancestor of the squid.
In 1956, during the Hungarian Revolution, the museum was burned down and the fossils were believed to have been destroyed. Rediscovery is a surprise.
When talking about rediscovery, Košťák said: “This is a great moment, seeing something that was previously suggested will definitely be lost.”
fossil. (Košťák and others, “Communication Biology”, 2021)
Košťák and his colleagues studied the fossils using scanning electron microscopes and performed geochemical analyses. They first discovered that Kretzoi’s original identity was correct: the fossil came from squid, not the ancestor of cuttlefish.
The animal’s inner shell, the swordfish that forms the backbone of its body, is about 6 inches (15 cm) long, which indicates that the squid grows to about 13.7 inches (35 cm) (including arms). This is only slightly larger than the modern vampire squid, which is about 11 inches (28 cm) in length.
There are no traces of microfossils that are often found on the seafloor in the sediments surrounding the fossils, indicating that the squid does not live in shallow water. The researchers also analyzed the change levels of carbon in the sediments and found that the sediments may come from anoxic or hypoxic environment.
These conditions are characteristic of the deep seabed. By observing fossils deposited in layers of rock outside of Budapest today, the researchers were also able to prove that squid might not be able to survive in the shallow seas at that time.
The shallow sea sediments show a high content of specific plankton that blooms in a low-salt, high-nutrient environment-conditions that modern vampire squid cannot tolerate.
(Researchers from the Monterey Bay Institute found that when these squids lurked in the deep sea, they did not behave like nightmare predators as their name implies; instead, they waited in a dark habitat for organic debris to be extinguished. Then, They captured the debris with suction cups covered in mucus, MBARI found.)
Adaptation depth
The new research was published in the journal on Thursday (February 18) Communication biology, Suggesting how the ancestors of the vampire squid learned to live where other squids could not.
Koschke said that from the deeper level of the fossil record, the oldest fossils in this group of squid were discovered during the Jurassic period (approximately 201 million to 174 million years ago) and are usually found in hypoxic sediments.
“The main difference is that these hypoxic conditions are determined on the shelf. [a] He said: “This means that the ancestors were residents of shallow water environments, but they have adapted to low oxygen environments.”
Since about 145 million years ago, there have been gaps in the fossil record of the Lower Cretaceous. Košťák said that by this point, the squid may have moved to deeper oceans, mainly due to their experience in Jurassic hypoxic conditions. He added that this deep-water lifestyle may explain why the squid survived the crisis of killing non-avian dinosaurs at the end of the Cretaceous.
Košťák said that the deep squids 30 million years ago helped to link modern history to the abyss. He and his colleagues are now trying to establish a similar connection for cuttlefish, a group of cute, discolored cephalopods whose origins are also dim.
related information:
Cuttlefish beauty: photos of discolored cephalopods
Photo: Vampire squid from hell
10 strange animals washed ashore in 2020
This article was originally published by Live Science. Read the original article here.
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