Latest news with #Ediacaran
Morocco World
05-08-2025
- Science
- Morocco World
Scientists Discover Rare Fossils from Earth's Earliest Ecosystems in Morocco
Rabat – A team of Moroccan and international scientists has uncovered rare fossils in the Anti-Atlas Mountains. The discovery could help solve one of the biggest mysteries in Earth's history: what happened during the transition from the Ediacaran period to the Cambrian explosion, over 540 million years ago. The discovery was made in the Tabia Member of the Adoudou Formation, near Ez-Zaouia village in the western Anti-Atlas. The research, published in Precambrian Research, describes previously unknown trace fossils, soft-bodied organisms, and mat-related structures (MRS), preserved in ancient rocks from the time when the first complex life began to evolve. This period, known as the Ediacaran-Cambrian transition, marks the end of the Ediacaran biota (soft-bodied life forms that lived in microbial mats) and the rise of more active, complex animals that define modern ecosystems. But how exactly this shift happened has long been debated. Researchers found fossilized signs of both life forms living at the same time, suggesting that this was not a sudden extinction but a gradual evolutionary change, where new animals began to replace the older ones. Among the findings were trace fossils such as Treptichnus bifurcus, Bergaueria, Helminthopsis, and Archaeonassa, which are tracks and burrows left by early moving animals. In addition, soft-bodied fossil discs like Aspidella and Nimbia, believed to be among the last representatives of the Ediacaran organisms, were also discovered. Findings also include mat-related structures, including surface wrinkles and textures formed by microbial life. These fossils show that different types of early life were sharing the same environments just before the Cambrian explosion. 'The Ediacaran–Cambrian transition has long been recognized as an important juncture in Earth's history. However, this boundary remains poorly understood in terms of the tempo and relationships among evolutionary, environmental, and ecological changes,' reads the research paper. The Adoudou Formation is already known among geologists as a key site for studying changes in the Earth's chemical record during this period. However, until now, its fossil content was not well understood. This study puts the Anti-Atlas region on the map as a crucial location for studying early life on Earth. Tags: DiscoveryfossilMorocco
Time of India
03-07-2025
- Science
- Time of India
5 oldest animal fossils ever discovered and who they belonged to
F ossils are like nature's time machines, giving us a peek into life on Earth millions of years ago. The oldest animal fossils tell stories about how complex life began and evolved. Be it simple creatures or bizarre primitive animals, these fossils help scientists understand the origins of life in oceans and beyond. Sometimes, certain fossil discoveries also push back the timeline of when animals first appeared, revealing unexpected shapes and forms. Here are some of the oldest animal fossils ever found! Dickinsonia Dickinsonia is one of the oldest known animal fossils, dating back over 550 million years. This strange, flat, oval-shaped organism lived during the Ediacaran period and resembled a giant pancake or a segmented leaf. Scientists debate whether Dickinsonia was a simple animal, fungus, or something else entirely, but recent research supports it being an early animal. It likely lived on the seafloor, absorbing nutrients. Its discovery helped redefine what we consider the earliest animal life. Kimberella Kimberella lived around 555 million years ago and is considered one of the earliest animals with a definite body plan. This soft-bodied creature had a shell-like covering and might be an early relative of mollusks like snails and clams. Kimberella shows evidence of movement and possibly a feeding structure, making it one of the first animals to graze on microbial mats. Its fossils hint at the beginning of more complex animal life before the famous Cambrian explosion. Spriggina Spriggina is a curious fossil from about 550 million years ago. It had a segmented, worm-like body and is thought to be related to early arthropods, the group that includes insects and crabs today. Its head and body segments suggest it had some level of organization and movement. Spriggina helps us understand the early evolution of animals with segmented bodies, which is a common design in many creatures today. Anomalocaris Anomalocaris lived during the Cambrian period around 520 million years ago and is one of the earliest known apex predators. This strange-looking creature had large compound eyes, a circular mouth with sharp plates, and two large grasping appendages for catching prey. Anomalocaris was a marine hunter, dominating early seas and showing that complex food chains existed even in Earth's ancient oceans. Hallucigenia Hallucigenia is famous for its unusual, almost alien appearance. It lived around 508 million years ago and had a long, soft body with spikes sticking out on top and legs underneath. For years, scientists misinterpreted its anatomy until better fossils revealed its true shape. Hallucigenia is related to velvet worms and helps scientists understand the diversity and experimentation in body forms during the Cambrian explosion. Haikouichthys Haikouichthys lived around 518 million years ago and is one of the earliest animals with a backbone. It looked like a small fish and had important features like a head, gills, and a notochord, which was a simple, early version of a spine. This little creature is super important because it marks a key step in the evolution of vertebrates, showing how animals started to develop more complex bodies and nervous systems that would lead to modern fish and eventually land animals.
Time of India
22-05-2025
- Science
- Time of India
Ikaria Wariootia: The earliest known animal ancestor on the planet has been discovered from South Australia
Scientists have identified Ikaria wariootia , a tiny, wormlike creature that lived over 555 million years ago, as the earliest known bilaterian — an animal with a front, back, and symmetrical sides. Detailed in the journal Proceedings of the National Academy of Sciences , this discovery from South Australia provides crucial evidence for a major evolutionary leap during the Ediacaran period: the origin of bilateral body structure, a key feature of nearly all animals today, including humans. Ikaria Wariootia: A peek into the first bilaterian animals Bilaterians are animals that exhibit bilateral symmetry, meaning their bodies have two symmetrical halves, each mirroring the other. This structure includes distinct head, tail, back, and belly, facilitating controlled movement and internal complexity. Scientists had long hypothesized that the earliest bilaterians would be simple, small, and possess basic sensory organs, but no fossil evidence had confirmed this—until the discovery of Ikaria wariootia . Measuring just 2 to 7 millimeters, this creature is about the size of a grain of rice. Dr. Scott Evans from the University of California, Riverside, explained, 'While we believed such animals existed during this time, we didn't expect them to be easy to identify. When we saw the 3D scans, we knew we had found something significant.' Using advanced 3D laser scanning, the team uncovered the fossil's cylindrical body, clear bilateral symmetry, and signs of musculature, marking a pivotal discovery in understanding early bilaterian life. Insights into ediacaran lie and the evolution of animals This discovery also changes how scientists perceive other Ediacaran organisms. While large, iconic species like Dickinsonia were previously considered evolutionary dead ends without any living descendants, smaller and simpler creatures like Ikaria may represent the earliest ancestors of bilaterians, the group that gave rise to most modern animals. "While Dickinsonia and similar large creatures were likely evolutionary dead ends, we also had many smaller organisms and suspected they might be the early bilaterians we were searching for," said Professor Droser. The identification of Ikaria wariootia bridges the gap between genetic theories and fossil records, confirming that early bilaterians had the body structure and abilities necessary for complex behaviors like directed movement and burrowing. Fossilized burrows provide evidence of purposeful movement in Ikaria Wariootia The discovery is linked to fossilized burrows known as Helminthoidichnites , found in the same geological layers in Nilpena, South Australia. For over 15 years, paleontologists speculated these burrows were created by bilaterians, but the exact organism remained unclear. The size and shape of Ikaria wariootia match these burrows, reinforcing the idea that the creature actively burrowed into oxygen-rich ocean-floor sand in search of organic matter. "Burrows of Ikaria wariootia are found deeper than any other, making it the oldest fossil with this level of complexity," said Professor Mary Droser. The fossil also shows V-shaped ridges in the burrows, indicating that Ikaria used peristaltic locomotion, contracting its muscles like modern worms. This type of movement suggests an advanced level of coordination and sensory input previously unknown in such early animals. Significance of this discovery by Proceedings of the National Academy of Sciences The discovery of Ikaria wariootia significantly reshapes our understanding of early animal evolution. Dating back 555 million years to the Ediacaran period, it is the earliest known bilaterian fossil, showing bilateral symmetry, a key feature of most modern animals. This discovery bridges the gap between genetic predictions and fossil evidence, supporting the idea that early bilaterians were small, simple creatures with complex capabilities, such as purposeful movement and burrowing. The fossil's association with Helminthoidichnites burrows suggests that Ikaria actively tunneled through oxygenated ocean-floor sand, indicating coordination and sensory input. This finding challenges prior assumptions about the pace of evolution, demonstrating that complex behaviors and body plans could have evolved much earlier than previously thought. Ikaria wariootia provides a crucial insight into the origins of animal complexity, marking a significant milestone in our understanding of the pre-Cambrian evolution of life on Earth. Fossil characteristics of Ikaria Wariootia The Ikaria wariootia fossil exhibits several key characteristics that make it a groundbreaking discovery in the study of early animal evolution. These characteristics are: Bilateral Symmetry The fossil shows clear evidence of bilateral symmetry, meaning it has a defined left and right side that mirror each other. This symmetry is a key trait of bilaterians, the group from which most modern animals, including humans, evolved. Small Size Ikaria wariootia measures just 2 to 7 millimeters long, roughly the size of a grain of rice. Its small size is consistent with its position as an early, simple bilaterian. Cylindrical Body Shape The fossil's cylindrical body, observed through 3D scanning, suggests a simple yet functional body plan, capable of basic movement and burrowing. Musculature Evidence The fossil displays signs of musculature, which support the idea that Ikaria could move in a coordinated manner, likely using peristaltic locomotion similar to modern worms. Burrow Association The fossil is linked to Helminthoidichnites burrows, which are V-shaped and indicative of active tunneling behavior. These burrows suggest that Ikaria moved purposefully through oxygenated ocean-floor sand, searching for organic matter. Complex Locomotion The presence of V-shaped ridges in the burrows indicates Ikaria used a form of peristaltic movement, contracting muscles across its body, highlighting an early form of coordinated, complex movement. Importance of discovery of Ikara wariootia The discovery of Ikaria wariootia provides valuable insights into early animal behavior, particularly in terms of its locomotion and environmental interactions. Here are some key behavioral implications: Purposeful Movement The presence of Ikaria wariootia in association with Helminthoidichnites burrows suggests that it actively tunneled through the ocean-floor sand. This implies that Ikaria was capable of purposeful movement, likely searching for organic matter. Such behavior indicates a level of coordination and sensory input, much like modern worms, which use their muscles to move in a controlled manner. Peristaltic Locomotion The V-shaped ridges observed in the burrows suggest that Ikaria used peristaltic movement—contracting muscles along its body to propel itself forward. This form of locomotion is still seen in modern worms and other simple animals, demonstrating that early bilaterians had complex movement abilities, likely enabling them to explore their environment more effectively. Environmental Interaction The burrowing behavior highlights Ikaria's interaction with its environment, particularly its use of oxygenated sand for shelter and feeding. This shows that early bilaterians were capable of modifying their surroundings, a trait that would evolve in later species to allow more complex forms of behavior, such as constructing shelters or hunting. Sensory and Nervous System Development The ability to move purposefully and burrow suggests that Ikaria had a developed nervous system that allowed it to respond to its environment and carry out coordinated actions. The presence of muscles, coupled with coordinated movement, implies the evolution of basic sensory input and motor control, essential for more complex behaviors in future animals. Adaptation to the Environment Ikaria's ability to move through oxygenated sand in search of food suggests early adaptations for survival, allowing it to exploit available resources efficiently. This reflects a fundamental aspect of animal behavior—the need to adapt to and interact with the environment to find food, shelter, and mates. Impact of Ikara wariootia on study of early life The discovery of Ikaria wariootia provides valuable insights into early animal behavior, particularly in terms of its locomotion and environmental interactions. Here are some key behavioral implications: Purposeful Movement The presence of Ikaria wariootia in association with Helminthoidichnites burrows suggests that it actively tunneled through the ocean-floor sand. This implies that Ikaria was capable of purposeful movement, likely searching for organic matter. Such behavior indicates a level of coordination and sensory input, much like modern worms, which use their muscles to move in a controlled manner. Peristaltic Locomotion The V-shaped ridges observed in the burrows suggest that Ikaria used peristaltic movement—contracting muscles along its body to propel itself forward. This form of locomotion is still seen in modern worms and other simple animals, demonstrating that early bilaterians had complex movement abilities, likely enabling them to explore their environment more effectively. Environmental Interaction The burrowing behavior highlights Ikaria's interaction with its environment, particularly its use of oxygenated sand for shelter and feeding. This shows that early bilaterians were capable of modifying their surroundings, a trait that would evolve in later species to allow more complex forms of behavior, such as constructing shelters or hunting. Sensory and Nervous System Development The ability to move purposefully and burrow suggests that Ikaria had a developed nervous system that allowed it to respond to its environment and carry out coordinated actions. The presence of muscles, coupled with coordinated movement, implies the evolution of basic sensory input and motor control, essential for more complex behaviors in future animals. Adaptation to the Environment Ikaria's ability to move through oxygenated sand in search of food suggests early adaptations for survival, allowing it to exploit available resources efficiently. This reflects a fundamental aspect of animal behavior—the need to adapt to and interact with the environment to find food, shelter, and mates. Also read: James Webb Space Telescope identified Milky Way's cosmic twin from the universe's first billion years
Forbes
14-04-2025
- Science
- Forbes
In 2018, Dickinsonia Was Classified As The Oldest Known Animal — A Biologist Explains
Here's why Dickinsonia challenges our previously held beliefs and changes how we view evolutionary ... More history. For the longest time, it was believed all complex animal life could be traced to the Cambrian explosion that occurred over 500 million years ago. However, the discovery of Dickinsonia, a now-iconic member of the Ediacaran biota and possibly the oldest macroscopic animal fossil recorded to date, challenges these notions and our understanding of evolution on Earth. Living approximately 558 million years ago — well before the rapid diversification of animal body plans in the Cambrian — Dickinsonia raised fundamental questions about growth, movement and the evolution of early developmental strategies. Its fossilized imprints challenged conventional narratives on the origin of complex life and provided direct clues about early animal physiology and ecology. Furthermore, the 2018 discovery of distinctive molecular signatures in fossils, particularly cholesterol derivatives, has transformed our view of these soft-bodied organisms and provided strong evidence for their classification as some of the earliest animals in evolutionary history. Dickinsonia was first discovered in the late 1940s in South Australia's Flinders Ranges. Paleontologist Reg Sprigg initially identified its distinctive quilted pattern and named it in honor of Ben Dickinson, a government official with the South Australian Mines Department. The Flinders Ranges are renowned for preserving some of the world's oldest known complex life forms. Over the ensuing decades, fossils of Dickinsonia were reported from several continents, including sites in Russia and Ukraine, suggesting a cosmopolitan distribution during the Ediacaran period. These organisms were preserved only as impressions or casts in quartz sandstones — typical of soft-bodied organisms that left little by way of hard skeletal parts. The unique traits of Dickinsonia include its bilaterally symmetric, oval shape with a pronounced anterior–posterior axis. Repeating modules or isomeres run along its length, arranged in an alternating fashion that some researchers interpret as a form of glide reflection symmetry rather than strict bilateral segmentation. Studies on Dickinsonia have thus steadily shifted its classification due to how difficult it has been for scientists to peg it to a particular species. Once hypothesized as a jellyfish, fungus or even a giant protist, science now favors an animal interpretation. For decades, Dickinsonia's placement in the Tree of Life was hotly debated. Early interpretations ranged from it being a member of the Cnidaria, a group including jellyfish and sea anemones, to suggestions that it was a fungus or even a giant single-celled protist. Morphological features alone proved insufficient to resolve its systematic position since Dickinsonia exhibits few structures similar to modern animals. However, with the emergence of innovative geochemical techniques, researchers began to look at the molecules trapped within the fossil tissues, moving beyond mere morphology. The discovery of animal-specific cholesterol derivatives in Dickinsonia fundamentally altered its classification and strongly argued against non-metazoan alternatives. This is because cholesterol and its degradation product cholestane are found exclusively in animal cell membranes, thus providing molecular evidence of an animal affinity. Researchers suspect it likely lived on shallow marine substrates where it 'crawled' slowly, feeding on microbial mats by external digestion — a behavior somewhat analogous to modern placozoans, the phylum of free-living, non-parasitic marine invertebrates. The current consensus, therefore, leans toward classifying Dickinsonia as an animal. More specifically, it may have been an early relative of simple animals like placozoans or part of a completely new branch of early animals that later gave rise to creatures with bilateral symmetry. Studies of its growth patterns have shown consistent evidence for a regulated developmental program, a signature trait of animal life. These findings have not only provided the positive evidence needed to affirm Dickinsonia's animal status but have also reshaped our understanding of the Precambrian evolutionary landscape. The discovery and classification of Dickinsonia have had profound implications for our understanding of the Cambrian explosion. This rapid burst of evolutionary innovation, beginning around 500 million years ago, gave rise to nearly all the modern animal phyla. Dickinsonia and other Ediacaran organisms were once viewed as evolutionary dead ends — enigmatic forms with no descendants. However, the mounting evidence that Dickinsonia was an animal forces us to reframe these early organisms not as isolated experiments but as integral steps in the progression toward more complex body plans. Recent research has demonstrated that Dickinsonia's biological features — their regulated modular growth, evidence of animal-specific biomolecules and locomotive trace fossils — establish them as a credible evolutionary bridge between simple, soft-bodied organisms and the complex hard-bodied animals that dominate the Cambrian fossil record. In this light, the Ediacaran biota, far from representing failed experiments, appears to have set the stage for the diversification of animal life as we know it today. Does reading about how all life on Earth possibly traces back half a billion years fill you with appreciation for nature's guiding hand? Take the Connectedness To Nature Scale and find out how deep your connection is with the natural world.
Forbes
06-04-2025
- Science
- Forbes
New Study Pinpoints Emergence Of First Animals
Tribrachidium heraldicum, one of the most enigmatic critters from the Ediacara-fauna. The Ediacaran, a geological period spanning from 635 to 538 million years ago, saw the emergence of the first complex multicellular animals after Earth was ruled for almost 3 billion years by microorganisms. First described from the Ediacara Hills in Australia, Ediacara-type fossils have been found in Newfoundland, England's Charnwood Forest, Namibia, Russia and China. The Ediacara fossils includes many weird organisms of unknown affinity, like Dickinsonia, an egg-shaped, segmented hybrid between a worm and a jellyfish, Charnia, a segmented and branched organism resembling superficially modern sea pens, or Tribrachidium, showing a threefold rotational symmetry not found in any modern creature. The beginning of the Ediacaran is marked by the Marinoan glaciation, a worldwide glaciation lasting from 654 to 632 million years ago. Its possible role in the emergence of the Ediacaran fauna has long been debated, with some researchers suggesting that the melting ice released nutrients into the sea, providing a fertile ground for complex life to evolve. In a new study, Chinese researchers used cyclostratigraphy to exactly date the aftermath of the Marinoan glaciation and the emergence of the Ediacara fauna, suggesting that oxygen pulses played a mayor role. Cyclostratigraphy analyzes astronomically-forced cycles preserved in sedimentary rocks. When integrated with radioisotope geochronology, a technology that uses the radioactive decay of elements to date rocks and minerals, it can produce a continuous, high-resolution geological time scale. Approximately 580 million years ago, South China was part of the northern coastline of the supercontinent Rodinia and positioned near the equator. The erosion of the still barren land produced a succession of black mudstone and white limestone layers. By studying this succession, the researchers discovered cycles lasting from 2.4 million years to 103,000 years, likely a result of orbital changes and shifting climate patterns. According to the new analysis, the Marinoan ice age was followed by a rapid sea-level rise, leading to the deposition of a thick layer of cap carbonate in just one to 10 million years. This marks a dramatic shift from a frozen world to a hot, high-carbon dioxide environment. The emergence of the earliest Ediacara-type fossils was dated to 619 to 587 million years, with species becoming progressively more complex over time. The rapid deglaciation influenced oceanic currents, leading to periodic pulses of oxygen reaching the deep sea. The emergence of new species, so the study's conclusions, coincides with these oxygenation events. The flattened body of many Ediacaran fossils suggests they adsorbed oxygen and nutrients directly from the water through their body surface. But this adaption made them vulnerable to low oxygen levels. A combination of volcanic eruptions, tectonic plate motion, maybe even an asteroid impact, at the end of the Ediacaran caused a drop in global oxygen levels, leading to the first mass extinction around 539 to 500 million years ago This extinction may have helped pave the way for the evolution of animals as we know them today. The study, "Astronomically calibrating early Ediacaran evolution," was published in the journal nature communications.
