Newly discovered claw-mark fossils suggest reptiles evolved earlier than we thought
When you buy through links on our articles, Future and its syndication partners may earn a commission.
Reptiles as we know them today may have evolved about 30 million years earlier than we initially assumed, new footprints reveal.
According to a study published Wednesday (May 14) in the journal Nature, fossilized tracks found in Australia may have been left by the clawed feet of a small reptile-like creature about 350 million years ago, during the Carboniferous period.
This new discovery would push back the evolution of these animals by roughly 30 million years, as early reptiles were previously thought to have evolved around 320 million years ago.
"Once we identified this, we realised this is the oldest evidence in the world of reptile-like animals walking around on land — and it pushes their evolution back by 35-to-40 million years older than the previous records in the Northern Hemisphere," study co-author John Long, a strategic professor of palaeontology at Flinders University in Australia, said in a statement.
"The implications of this discovery for the early evolution of tetrapods are profound."
Modern reptiles, along with birds and mammals, are part of a group of animals known as amniotes, which are defined as tetrapod vertebrates (four-limbed animals with backbones) that lay eggs equipped with a protective membrane that surrounds the embryo. This so-called amnion allows eggs to be laid on land, freeing early land animals from dependency on water for reproduction. This is in contrast to amphibians, which rely on moist environments to reproduce.
Related: Which animal species has existed the longest?
Amniotes evolved from amphibian-like ancestors, with the earliest amniote body fossils being dated to the late Carboniferous Period, which spanned from approximately 359 to 299 million years ago. These early amniotes, which were small, lizard-like creatures, then diversified into two groups: synapsids and sauropsids, which evolved into the earliest ancestors of mammals and reptiles, respectively.
Based on the fossil record, amniotes were thought to have evolved around 320 million years ago. However, this new discovery of clawed amniote footprints in Australia from 350 million years ago throws these estimations hugely off.
"I'm stunned," study co-author Per Ahlberg, a professor of paleontology at Uppsala University, said in a statement. "A single track-bearing slab, which one person can lift, calls into question everything we thought we knew about when modern tetrapods evolved."
These footprints were discovered on a 20-inch (50cm) rock slab by two amateur palaeontologists in the Snowy Plains Formation in Australia's Victoria, which dates back to 350 million years ago. The footprints appeared to have been made by a creature with clawed feet and long toes, likely an early sauropsid, meaning that reptiles may have been around much earlier than we assumed.
"Claws are present in all early amniotes, but almost never in other groups of tetrapods," Ahlberg said. "The combination of the claw scratches and the shape of the feet suggests that the track maker was a primitive reptile."
These footprints are the earliest clawed prints ever discovered.
"When I saw this specimen for the first time, I was very surprised," study co-author Grzegorz Niedźwiedzki, a researcher at Uppsala University, said in the statement.
RELATED STORIES
—'Exquisitely preserved' ginormous claws from Mongolia reveal strange evolution in dinosaurs
—See the reconstructed home of 'polar dinosaurs' that thrived in the Antarctic 120 million years ago
—Hoatzin: The strange 'stinkbird' born with clawed wings that appears to be an evolutionary 'orphan'
Pushing back the tree of reptilian evolution, the researchers concluded that reptiles may have actually evolved towards the end of the Devonian period, when primitive fish-like creatures like Tiktaalik roamed the land.
"It's all about the relative length of different branches in the tree," Ahlberg said. "In a family tree based on DNA data from living animals, branches will have different lengths reflecting the number of genetic changes along each branch segment. This does not depend on fossils, so it's really helpful for studying phases of evolution with a poor fossil record."
Niedźwiedzki added: "The most interesting discoveries are yet to come and that there is still much to be found in the field. These footprints from Australia are just one example of this."
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
27 minutes ago
- Yahoo
James Webb telescope unveils largest-ever map of the universe, stretching from present day to the dawn of time
When you buy through links on our articles, Future and its syndication partners may earn a commission. Scientists have unveiled the largest map of the universe ever created. Stretching across a tiny sliver of space and almost all cosmic time, it includes almost 800,000 galaxies imaged across the universe. Some are so far away that they appear as they existed in the infant universe, about 13 billion years ago. The map, released Thursday (June 5) by scientists at the Cosmic Evolution Survey collaboration , covers a 0.54-degree-squared arc of the sky, or about three times as much space as the moon takes up when viewed from Earth. To collect the data for the map, the James Webb Space Telescope (JWST) spent 255 hours observing a region of space nicknamed the COSMOS field. This patch of sky has very few stars, gas clouds or other features blocking our view of the deep universe, so scientists have been surveying it with telescopes across as many wavelengths of light as possible. JWST's observations of the COSMOS field have given us an incredibly detailed view of the universe going back as far as 13.5 billion years. Because the universe has been expanding, visible light that left its source at the other side of the universe gets stretched out, becoming infrared light. This is why JWST was designed to be an extremely sensitive infrared telescope: to detect these faint, stretched-out signals from the beginning of time that we couldn't see with other telescopes. It's already reshaping our understanding of how the universe formed. RELATED STORIES —Catastrophic collision between Milky Way and Andromeda galaxies may not happen after all, new study hints —Universe may revolve once every 500 billion years — and that could solve a problem that threatened to break cosmology —Scientists discover smallest galaxy ever seen: 'It's like having a perfectly functional human being that's the size of a grain of rice' "Since the telescope turned on we've been wondering 'Are these JWST datasets breaking the cosmological model?" Caitlin Casey, a professor of physics at the University of California, Santa Barbara and co-lead for the COSMOS project, said in a statement. "The big surprise is that with JWST, we see roughly 10 times more galaxies than expected at these incredible distances. We're also seeing supermassive black holes that are not even visible with Hubble." The raw data from the COSMOS field observations was made publicly available just after it was collected by JWST, but it wasn't easily accessible. Raw data from telescopes like JWST needs to be processed by people with the right technical knowledge and access to powerful computers. The COSMOS collaboration spent two years creating the map from JWST's raw data to make it more accessible for amateur astronomers, undergraduate researchers and the general public to peer into the heart of the universe. You can see it for yourself using COSMOS' interactive map viewer.
Yahoo
2 hours ago
- Yahoo
The sun: Facts about the bright star at the center of the solar system
When you buy through links on our articles, Future and its syndication partners may earn a commission. Quick facts about the sun How big it is: 865,000 miles (1.392 million kilometers) across How far away it is: 93 million miles (150 million km) What type of star it is: A yellow dwarf star The sun is the star at the center of our solar system. It's the largest, brightest and most massive object in the solar system, and it provides the light and heat that life on Earth depends on. Powered by a process called nuclear fusion, the sun can get hotter than 27 million degrees Fahrenheit (15 million degrees Celsius). The sun has been around for over 4 billion years, but one day, it will run out of fuel. Read on to learn more about what our local star is made of, how it formed and what will happen when it dies. Over 1 million Earths could fit inside the sun. The sun may look yellow from Earth, but it actually releases every color of light, meaning its true color is white. The sun is unique in that it's the only star in our solar system. Up to 85% of stars have at least one companion star. The sun contains over 99% of the mass of our entire solar system. Like Earth, the sun also rotates on its axis. Each rotation takes about 27 Earth days. The sun is a ball of gas and plasma made mostly of hydrogen. The sun uses these vast stores of hydrogen to generate the heat and light that sustain our planet. It does this through a process called nuclear fusion, in which two hydrogen atoms combine to create a different element, helium. The sun is about three-quarters hydrogen and one-quarter helium, with tiny amounts of metals. The larger a star is, the more rapidly it burns through its hydrogen. Some of the largest known stars — such as those with masses 40 times that of the sun — will live just 1 million years. By contrast, the sun will have a lifetime of around 10 billion years. Different parts of the sun reach different temperatures. The sun's core gets as hot as 27 million F (15 million C). The part of the sun we can see from Earth is called the photosphere, which is the "surface" of the huge ball of plasma. The temperature of the photosphere is about 9,900 F (5,500 C). Above the photosphere is the loose outer atmosphere of the sun, known as the corona. We can't see the corona from Earth under ordinary conditions, though it can be photographed during a total solar eclipse. The sun formed around 4.5 billion years ago. At that time, the area of the Milky Way galaxy that would become the solar system was a dense cloud of gas — the leftovers of an earlier generation of stars. The densest region of this cloud collapsed and created a seed, called a protostar, that would become the sun. As this young protostar grew, planets, moons and asteroids formed from the remaining raw material, and then began circling around the growing sun as they were sucked into orbit by the star's powerful gravity. At the heart of the sun, this same force sparked nuclear fusion. The heat and light from this nuclear reaction allowed life on Earth to evolve and prosper. However, this reaction will eventually lead to the sun's death when it runs out of nuclear fuel. The sun is around halfway through its lifetime. Our star is locked in a constant battle as outward pressure from nuclear fusion fights the inward pull of gravity. When the sun runs out of hydrogen in about 5 billion years, the inward force of gravity will win. The center of the sun will collapse, compressing into a dense core. Helium will start fusing into even denser elements, like carbon, nitrogen and oxygen. While this happens, the heat generated by the fusing of these elements will push the sun's outer shell to swell. This will be bad news for the inner planets of the solar system — including Earth. As the sun becomes a type of star called a red giant, its outer shell will expand to the orbit of Mars, gobbling up Mercury, Venus, Earth and Mars. But the red-giant phase is not when the sun will die. The outer layers that swell during the red-giant phase will become a shell of gas called a surrounding planetary nebula. This shell will be shed after approximately 1 billion years. This will expose the star's smoldering core, which, by this point, will be a dense ball called a white dwarf. As a white dwarf, the sun will dim. The material from the planetary nebula will spread out into the galaxy and form the building blocks of the next generation of stars and planets. Image 1 of 5 Space agencies have launched many spacecraft that help us observe and gather data about the sun. Pictured here is an artist's concept of the sun being observed by NASA's Parker Solar Probe. Image 2 of 5 The red giant star Camelopardalis. The sun will eventually become a red giant, and as it expands, it will engulf its nearest planets, including Earth. Image 3 of 5 Sunspots are darker, cooler areas that temporarily appear on the sun. They're caused by changes in the sun's magnetic field. Image 4 of 5 Solar storms happen when the sun releases flares of energy and particles. Image 5 of 5 Auroras on Earth happen when charged particles from the sun interact with our planet's atmosphere. Is Earth getting closer to the sun, or farther away? Where on Earth does the sun rise first? What color is the sun?
Yahoo
2 hours ago
- Yahoo
Catch Jupiter and Mercury side by side in the evening sky this week
When you buy through links on our articles, Future and its syndication partners may earn a commission. The nights surrounding June 7 will see Jupiter and Mercury crowd together close to the horizon in the northwestern sky. Stargazers in the U.S. will need a clear horizon to spot the planetary duo hanging less than 10 degrees (about a fist's width at arm's length) above the western horizon when the sun sets on June 6, with Jupiter positioned to the upper left of Mercury. The planets will only be visible for around 45 minutes after sunset, at which time they will follow our star below the horizon. The following evenings will see fleet-footed Mercury draw level with Jupiter, before rising above and away from the gas giant in the night sky as a result of the smaller world's tight orbit around the sun. On June 7, the planets will pass a little over two degrees from each other - close enough to fit comfortably inside the field of view of a pair of 10x50 binoculars. Ensure that the sun has set entirely below the horizon before you point any binoculars or telescopic gear in its direction. Side by side in the night sky, the two points of light appear similar in nature, belying the extreme differences of the solar system bodies they represent. Jupiter is a gas giant and the largest planet in our solar system, capable of fitting the smallest planet - rocky Mercury - within its expanse many thousands of times over. Want to find the planets of our solar system for yourself? The Celestron NexStar 4SE is ideal for beginners wanting quality, reliable and quick views of celestial objects. For a more in-depth look at our Celestron NexStar 4SE review. Their orbits are similarly divergent. It takes Jupiter 12 Earth years to complete a single lap of our star while travelling at an average orbital distance of 484 million miles (778 million kilometers). Counterintuitively, the gas giant has the shortest day of any planet in the solar system, taking a mere 9.9 hours to spin on its axis, according to NASA. Mercury, on the other hand, is separated on average by 29 million miles (47 million kilometers) from our star and completes a circuit of the sun every 88 Earth days — much shorter than the 176 Earth days that it takes for the tortured world to complete a full day-night cycle. Night sky enthusiasts hoping to explore the planets of our solar system for themselves should check out our guides to the best binocular and telescope deals. Those new to the night sky should also read our guide detailing the top smartphone stargazing apps available in 2025. Editor's Note: If you capture a picture of Jupiter and Mercury and want to share it with readers, then please send it along with your comments, name and the location of the shoot to spacephotos@
