Latest news with #Anatolepis
Yahoo
6 days ago
- Health
- Yahoo
Have Sensitive Teeth? Scientists Say They May Have Evolved to Feel—Not Chew
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Here's what you'll learn when you read this story: A new study from the University of Chicago suggests our sensitive teeth may be an evolutionary leftover that once helped our fishy ancestors sense their surroundings. Researchers studied modern fish with dermal teeth and determined they are innervated, meaning they deliver sensory signals through nerves like our own teeth would. The study supports the 'outside-in' theory which suggests sensitive 'teeth' developed on exoskeletons before they appeared in mouths. Some would say there's nothing better than taking a big ol' bite out of an ice cream cone—but that's not necessarily a popular opinion. If the thought of sinking your pearly whites into a frozen dessert makes you cringe, then you probably have something in common with our earliest fishy ancestors. According to a new study published in Nature, teeth may have originated as sensory organs that helped ancient fish navigate murky waters. 'When you think about an early animal like this, swimming around with armor on it, it needs to sense the world,' senior author of the new study Neil Shubin said in a press release. 'This was a pretty intense predatory environment and being able to sense the properties of the water around them would have been very important. So, here we see that invertebrates with armor like horseshoe crabs need to sense the world too, and it just so happens they hit on the same solution.' Lead researcher on the study Yara Haridy wasn't always looking for ancient smiles—she made the discovery while trying to find the oldest vertebrate in the fossil record. Haridy identified armor bumps called odontodes on samples of the Cambrian fossil Anatolepis. It seemed like there were dentine tubules just beneath the odontodes—a hallmark sign of a vertebrate. Upon further inspection, Haridy realized the tubules were more akin to the sensory organs on crabs' shells called sensilla, although the pockets did contain dentin (A.K.A. the hard tissue that makes up the teeth in your mouth). The discovery sparked a new hypothesis for Haridy and the rest of the team: teeth may be sensory even when they're not in the mouth. 'We've been wondering 'why would we chew with these painful things? Why are they so sensitive in the first place?' Haridy said in a video. 'And it turns out, maybe this is a leftover from one of our most ancient ancestors.' Surprisingly, external teeth aren't uncommon in the animal kingdom today. Sharks, skates, and catfish all have tiny tooth-like structures called denticles lining their skin, making them feel like sandpaper. To better understand whether these external teeth were innervated (connected to nerves), Haridy studied some modern fish with denticles. She determined that the denticles were, in fact, connected to nerves like human teeth would be. Haridy said in the press release that the resemblance between armored fish's denticles and the sensilla of arthropods (like the ones seen in the Anatolepis samples) was striking. 'We think that the earliest vertebrates, these big, armored fish, had very similar structures, at least morphologically.' she said. 'They look the same in ancient and modern arthropods, because they're all making this mineralized layer that caps their soft tissue and helps them sense the environment,' According to Shubin, these early sea creatures would have existed in a 'pretty intense predatory environment,' so the ability to sense the world swimming around them would have been extremely important. The team's findings support what is known as the 'outside-in' hypothesis, or the theory that sensitive structures developed on exoskeletons first and then sensitive teeth followed. This contradicts the 'inside-out' hypothesis that assumes teeth arose first and were later adapted for exoskeletons. 'The more we look at the fossil record, the more we put those fossils in an evolutionary sequence, the more that we see the 'outside-in' hypothesis is likely correct,' Shubin said in the video. 'Our teeth originally evolved as the armor on the outside of the body of the earliest fish.' Moral of the story is: next time an annual cleaning leaves you with a toothache, don't blame the dental hygienist—blame your gilled ancestors! You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Sustainability Times
26-05-2025
- Science
- Sustainability Times
This Prehistoric Armored Fish From 465 Million Years Ago Could Be the Key to Understanding Why Our Teeth Still Hurt
IN A NUTSHELL 🦈 Researchers discovered that ancient armored fish from 465 million years ago had sensory structures similar to human dentine. similar to human dentine. 🔍 The study supports the 'outside-in' hypothesis, suggesting teeth evolved from external sensory mechanisms found in ancient fish. from external sensory mechanisms found in ancient fish. 🦀 Evolutionary convergence was observed as both vertebrates and arthropods independently developed similar sensory organs for environmental detection. for environmental detection. 📜 Advanced imaging techniques corrected past misinterpretations, revealing that Anatolepis was not an early vertebrate but an ancient arthropod. Recent discoveries in paleontology have shed light on a fascinating connection between ancient armored fish and modern human tooth pain. Fossils from 465 million years ago, specifically of a jawless vertebrate fish, have revealed that the origins of tooth pain might trace back to the sensory capabilities of these early creatures. This study, conducted by researchers at the University of Chicago, uncovers how the sensory mechanisms in these ancient fish might have evolved into the pain-sensitive dentine found in human teeth today. The implications of these findings are profound, offering insights into the evolutionary processes that have shaped the way we experience sensation and pain. The Evolutionary Link Between Fish and Teeth The discovery of sensory structures in ancient fish provides a crucial link in understanding the evolution of teeth. The study identified that the bumps on the armored skin of these fish, known as odontodes, were composed of dentine. This material is a key component of human teeth, responsible for transmitting sensations of pain when exposed to stimuli like cold or pressure. Researchers used advanced 3D scanning techniques to analyze the fossils, confirming that these odontodes were not merely protective armor but also served a sensory function. These findings suggest that long before vertebrates developed internal skeletons and complex dental structures, they had external sensory mechanisms embedded in their skin. This supports the 'outside-in' hypothesis, which posits that teeth evolved from external sensory structures. By tracing the evolutionary lineage of these sensory capabilities, scientists can better understand not only the origin of teeth but also the intricate ways evolution repurposes biological structures for new functions. '8,000 Dinosaur Bones Found': Canada's Fossil Graveyard Reveals One of the Most Terrifying Prehistoric Mass Death Sites Ever Unearthed Convergence of Sensory Structures in Different Species The phenomenon of evolutionary convergence is vividly illustrated in this study. Despite evolving independently, both vertebrates like fish and invertebrates such as arthropods developed similar sensory structures. The research highlights that the sensory organs, or sensilla, found in the shells of arthropods are strikingly similar to the odontodes of ancient fish. This convergence is remarkable, given the vast evolutionary distances separating these groups and their last common ancestor, which likely lacked any hard parts. Dr. Yara Haridy, who led the research, emphasized this point by comparing the sensory structures in fish and arthropods. The study revealed that these features evolved independently but served analogous functions in sensing environmental changes. This discovery not only clarifies previously misunderstood aspects of the fossil record but also underscores the adaptive nature of evolution, where different species arrive at similar solutions to environmental challenges. China Stuns the World by Firing Precision Laser at the Moon in Daylight, Reaching Historic Deep-Space Targeting Milestone Revisiting the Fossil Record: Anatolepis and Misinterpretations The study also revisits and rectifies historical misinterpretations in paleontology. For years, the fossil of Anatolepis, a Cambrian-era organism, was mistaken for an early vertebrate due to its tooth-like surface structures. However, upon closer examination with high-resolution CT scans, researchers determined these structures lacked dentine, identifying them instead as sensilla akin to those found in arthropods. This correction is significant as it shifts the understanding of early vertebrate evolution and highlights the challenges paleontologists face in interpreting fossil evidence. The case of Anatolepis exemplifies how advanced imaging techniques can refine our knowledge of ancient life forms and their evolutionary pathways. By distinguishing between actual vertebrate features and those merely resembling them, scientists continue to build a more accurate picture of the evolutionary timeline. 'Candle on the Moon Detected': This Underground Lab's Mind-Blowing Sensitivity Is Rewriting the Limits of Human Technology The Broader Implications of Sensory Evolution Understanding the sensory capabilities of ancient fish not only illuminates the history of vertebrate evolution but also offers insights into the broader principles guiding the development of sensory systems. The study's findings suggest that the fundamental mechanisms of sensation, such as the interaction between nerves and mineralized structures, have deep evolutionary roots. Moreover, this research has potential implications for modern biology and medicine. By exploring the origins of sensory systems, scientists can gain insights into how these systems function in contemporary organisms, including humans. This knowledge may inform the development of treatments for sensory disorders or inspire biomimetic designs in technology. As researchers continue to uncover the connections between ancient and modern sensory mechanisms, they invite further inquiry into the evolutionary forces shaping life on Earth. The exploration of ancient sensory structures in fish not only enriches our understanding of evolutionary biology but also prompts intriguing questions about the nature of sensation itself. How might future studies further unravel the complex pathways from prehistoric sensory mechanisms to the sophisticated systems present in today's creatures? The answers may lie deep within the fossilized remains of Earth's earliest inhabitants, waiting to illuminate the intricate tapestry of life's history. What other evolutionary secrets remain hidden in the ancient past, waiting to be discovered? Our author used artificial intelligence to enhance this article. Did you like it? 4.6/5 (28)
Observer
24-05-2025
- Science
- Observer
Teeth hurt? It could be because of a 500-million-year-old fish
Ever wondered why our teeth are so sensitive to pain or even just cold drinks? It might be because they first evolved for a very different purpose than chewing half a billion years ago, a study suggested Wednesday. The exact origin of teeth -- and what they were for -- has long proved elusive to scientists. Their evolutionary precursors are thought to be hard structures called odontodes which first appeared not in mouths but on the external armour of the earliest fish around 500 million years ago. Even today, sharks, stingrays and catfish are covered in microscopic teeth that make their skin rough like sandpaper. There are several theories for why these odontodes first appeared, including that they protected against predators, helped with movement through the water or stored minerals. But the new study published in the journal Nature supports the hypothesis that they were originally used as sensory organs which transmitted sensations to nerves. At first, the study's lead author Yara Haridy was not even trying to hunt down the origins of teeth. Instead the postdoctoral researcher at the University of Chicago was probing another major question puzzling the field of palaeontology: what is the oldest fossil of an animal with a backbone? Haridy asked museums across the United States to send her hundreds of vertebrate specimens -- some so small they could fit on the tip of a toothpick -- so she could analyse them using a CT scanner. She began focusing on dentine, the inner layer of teeth that sends sensory information to nerves in the pulp. - Things get fishy - A fossil from the Cambrian period called Anatolepis seemed to be the answer she was looking for. Its exoskeleton has pores underneath the odontodes called tubules that could indicate they once contained dentine. This has previously led paleontologists to believe that Anatolepis was the first known fish in history. But when Haridy compared it to the other specimens she had scanned, she found that the tubules looked much more like sensory organs called sensilla of arthropods, a group of animals that includes crustaceans and insects. The mighty Anatolepis was therefore demoted to the rank of an invertebrate. For modern arthropods such as crabs, scorpions and spiders, sensilla are used to perceive temperature, vibration and even smell. How little these features have changed over time suggests they have been serving these same functions for half a billion years. The researchers said they found "striking" similarities between these features in Anatolepis and vertebrate fish from around 465 million years ago -- as well as some better-known fish. "We performed experiments on modern fish that confirmed the presence of nerves in the outside teeth of catfish, sharks and skates," Haridy told AFP. This shows that "tooth tissues of odontodes outside the mouth can be sensitive -- and perhaps the very first odontodes were as well," she added. "Arthropods and early vertebrates independently evolved similar sensory solutions to the same biological and ecological problem." Senior study author Neil Shubin, also from the University of Chicago, said that these primitive animals evolved in "a pretty intense predatory environment". "Being able to sense the properties of the water around them would have been very important," Shubin said in a statement. Haridy explained that over time, fish evolved jaws and "it became advantageous to have pointy structures" near their mouth. "Little by little some fish with jaws had pointy odontodes at the edge of the mouth and then eventually some were directly in the mouth," she said. "A toothache is actually an ancient sensory feature that may have helped our fishy ancestors survive!" —AFP
Yahoo
22-05-2025
- Science
- Yahoo
Tooth pain's origins traced to 465-million-year-old armored fish with sensors
Ever wonder why teeth hurt? Blame it on a prehistoric armored the outer layer of our teeth is coated in hard enamel, it's the inner layer, called dentine, that feels pain. Dentine carries signals to the nerves when we bite into something hard, or feel the sting of ice cream or sweetness. Scientists have long debated where teeth came from. One idea was that they evolved from small bumps on the tough outer shells of ancient fish. These bumps, known as odontodes, were once a mystery. But now, a new study confirms that these structures in an early vertebrate fish from the Ordovician period, about 465 million years ago, contained dentine. Using 3D scans on fossils of the fish, researchers discovered that these bumps were sensitive and were likely used to sense their environment, like detecting cold water or pressure from nearby objects. While studying the fossils, the team also found that odontodes in ancient fish looked a lot like sensilla — tiny sensory organs found in the shells of animals like crabs and shrimp. Sensilla are also seen in fossils of ancient invertebrates. Surprisingly, these two features evolved in completely different animal groups: fish, which have backbones, and arthropods, which don't. According to Dr. Yara Haridy, who led the study, this is a classic case of evolutionary convergence — when different species develop similar traits on their own. 'These jawless fish and Aglaspidid arthropods (extinct marine arthropods) have an extremely distant shared common ancestor that likely had no hard parts at all,' Haridy said. 'We know that vertebrates and arthropods evolved hard parts independently and amazingly they evolved similar sensory mechanisms integrated into their hard skeleton independently.' The findings also help explain a long-standing mix-up in the fossil record. For decades, a Cambrian-era fossil called Anatolepis was thought to be one of the earliest vertebrates, thanks to tooth-like bumps on its surface. But when the researchers closely examined the fossil using high-resolution CT scans, they realized those bumps didn't contain dentine after all. Instead, they looked just like the sensory structures — sensilla — seen in arthropods. That meant Anatolepis wasn't a vertebrate fish, but likely an ancient arthropod. The confusion, it turns out, is understandable. Sensory armor evolved in both vertebrates and invertebrates, and it often looks strikingly similar under the microscope. That's because both groups developed ways to sense their environment using nerve-connected structures embedded in hard outer coverings — whether it was fish skin or crab shell. To compare these features more broadly, the team scanned fossils and modern specimens ranging from snails and barnacles to sharks and catfish. One discovery stood out: suckermouth catfish raised in Haridy's own lab had small tooth-like scales on their skin — called denticles — that were directly connected to nerves. These denticles, like the ancient odontodes and arthropod sensilla, weren't just armor — they were sensory tools. 'We think that the earliest vertebrates, these big, armored fish, had very similar structures,' Haridy said. 'They look the same in ancient and modern arthropods because they're all making this mineralized layer that caps their soft tissue and helps them sense the environment.' This research also adds weight to a key theory in evolutionary biology. Called the "outside-in" hypothesis, the theory suggests that teeth evolved from external sensory structures like these. In other words, long before animals had mouths full of teeth, they had sensitive armor that helped them survive. While they didn't pin down the earliest vertebrate fish, Neil Shubin, the senior author of the study, said this discovery was more than worth the effort. 'For some of these fossils that were putative early vertebrates, we showed that they're not. But that was a bit of misdirection,' he said. 'We didn't find the earliest one, but in some ways, we found something way cooler.' The study has been published in the journal Nature.
NDTV
21-05-2025
- Science
- NDTV
Teeth Hurt? It Could Be Because Of A 500-Million-Year-Old Fish
Ever wondered why our teeth are so sensitive to pain or even just cold drinks? It might be because they first evolved for a very different purpose than chewing half a billion years ago, a study suggested Wednesday. The exact origin of teeth -- and what they were for -- has long proved elusive to scientists. Their evolutionary precursors are thought to be hard structures called odontodes which first appeared not in mouths but on the external armour of the earliest fish around 500 million years ago. Even today, sharks, stingrays and catfish are covered in microscopic teeth that make their skin rough like sandpaper. There are several theories for why these odontodes first appeared, including that they protected against predators, helped with movement through the water or stored minerals. But the new study published in the journal Nature supports the hypothesis that they were originally used as sensory organs which transmitted sensations to nerves. At first, the study's lead author Yara Haridy was not even trying to hunt down the origins of teeth. Instead the postdoctoral researcher at the University of Chicago was probing another major question puzzling the field of palaeontology: what is the oldest fossil of an animal with a backbone? Haridy asked museums across the United States to send her hundreds of vertebrate specimens -- some so small they could fit on the tip of a toothpick -- so she could analyse them using a CT scanner. She began focusing on dentine, the inner layer of teeth that sends sensory information to nerves in the pulp. THINGS GET FISHY A fossil from the Cambrian period called Anatolepis seemed to be the answer she was looking for. Its exoskeleton has pores underneath the odontodes called tubules that could indicate they once contained dentine. This has previously led paleontologists to believe that Anatolepis was the first known fish in history. But when Haridy compared it to the other specimens she had scanned, she found that the tubules looked much more like sensory organs called sensilla of arthropods, a group of animals that includes crustaceans and insects. The mighty Anatolepis was therefore demoted to the rank of an invertebrate. For modern arthropods such as crabs, scorpions and spiders, sensilla are used to perceive temperature, vibration and even smell. How little these features have changed over time suggests they have been serving these same functions for half a billion years. The researchers said they found "striking" similarities between these features in Anatolepis and vertebrate fish from around 465 million years ago -- as well as some better-known fish. "We performed experiments on modern fish that confirmed the presence of nerves in the outside teeth of catfish, sharks and skates," Haridy told AFP. This shows that "tooth tissues of odontodes outside the mouth can be sensitive -- and perhaps the very first odontodes were as well," she added. "Arthropods and early vertebrates independently evolved similar sensory solutions to the same biological and ecological problem." Senior study author Neil Shubin, also from the University of Chicago, said that these primitive animals evolved in "a pretty intense predatory environment". "Being able to sense the properties of the water around them would have been very important," Shubin said in a statement. Haridy explained that over time, fish evolved jaws and "it became advantageous to have pointy structures" near their mouth. "Little by little some fish with jaws had pointy odontodes at the edge of the mouth and then eventually some were directly in the mouth," she said. "A toothache is actually an ancient sensory feature that may have helped our fishy ancestors survive!"
