In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (2024)

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (1)

Ad Feedback

By Ashley Strickland, CNN

3 minute read

Published 12:30 AM EDT, Fri March 13, 2020

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (4)

This artist's illustration shows a young Purussaurus attacking a ground sloth in Amazonia 13 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (5)

This bundle of bones is the torso of another marine reptile inside the stomach of a fossilized ichthyosaur from 240 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (6)

Researchers uncovered the fossilized fragments of 200,000-year-old grass bedding in South Africa's Border Cave.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (7)

Meet Sasha, the preserved and reconstructed remains of a baby woolly rhinoceros named that was discovered in Siberia.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (8)

Stone tools made from limestone have helped researchers to suggest that humans arrived in North America as early as 30,000 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (9)

This image shows both sides of the 1.4 million-year-old bone handaxe made from the femur of a hippopotamus. It was most likely crafted by ancient human ancestors like hom*o erectus.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (10)

This illustration shows Kongonaphon kely, a newly described reptile that was an early ancestor of dinosaurs and pterosaurs. The fossil was found in Madagascar. It lived about 237 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (11)

The Okavango Delta in Botswana showcases a patchy landscape where the ability to plan results in a huge survival payoff.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (12)

This is a clutch of fossilized Protoceratops eggs and embryos, discovered in the Gobi Desert of Mongolia. They provide evidence that dinosaurs laid soft-shell eggs.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (13)

These tools, made from the bones and teeth of monkeys and smaller mammals, were recovered from Fa-Hien Lena cave in Sri Lanka. The sharp tips served as arrow points.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (14)

This labeled map shows the complete ancient Roman city of Falerii Novi as it currently exists underground.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (15)

Fragments of the Dead Sea Scrolls found in the 1950s are seen here.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (16)

This is one of the 408 human footprints preserved at the Engare Sero site in Tanzania. The fossilized footprints reveal a group of 17 people that traveled together, likely including 14 women, two men and one juvenile male.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (17)

Blade-like stone tools and beads found in Bulgaria's Bacho Kiro cave provide the earliest evidence for modern humans in Europe 47,000 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (18)

This artist's illustration shows what an early, small ichthyosaur that lived 248 million years ago may have looked like. It resembled a cross between a tadpole and a seal, grew to be one foot long and had pebble-like teeth that it likely used to eat invertebrates like snails and bivalves.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (19)

This is an artist's illustration of Adalatherium hui, an early mammal that lived on Madagascar 66 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (20)

This is an artist's illustration showing a cross-section of Earth's forming crust approximately 3 to 4 billion years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (21)

Illuminated medieval manuscripts are full of intricate decorations, illustrations and colors, including "endangered colors" that can no longer be recreated today.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (22)

These monkeys can be found in ancient Grecian frescoes. And the details are so accurate that researchers were able to identify them as vervet monkeys and baboons.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (23)

Archeologists have found the oldest string of yarn at a prehistoric site in southern France. This photograph, taken by digital microscopy, shows that of the cord fragment, which is approximately 6.2 mm long and 0.5 mm wide.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (24)

This illustration shows Elessaurus gondwanoccidens, a long-legged reptile that lived in South America during the Early Triassic Period. It's a cousin to other mysterious early reptiles that arose after the Permian mass extinction event 250 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (25)

The skeletal remains of hom*o antecessor are on display in this image. A recent study suggests antecessor is a sister lineage to hom*o erectus, a common ancestor of modern humans, Neanderthals and Denisovans.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (26)

A nearly two-million-year-old hom*o erectus skullcap was found in South Africa. This is the first fossil of erectus to be found in southern Africa, which places it in the area at the same time as other ancient human ancestors.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (27)

This painting shows what Antarctica may have looked like 90 million years ago. It had a temperate swampy rainforest.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (28)

This artist's illustration of Dineobellator notohesperus shows them in an open landscape, across what is now New Mexico, along with Ojoceratops and Alamosaurus in the background.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (29)

Ikaria wariootia was a worm-like creature that lived 555 million years ago. It represents the oldest ancestor on the family tree for most animals.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (30)

This is the 3.67-million-year-old 'Little Foot' skull. The view from the bottom (right) shows the original position of the first cervical vertebra, which tells us about her head movements and blood flow to the brain.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (31)

This is an artist's illustration of the world's oldest modern bird, Asteriornis maastrichtensis, in its original environment. Parts of Belgium were covered by a shallow sea, and conditions were similar to modern tropical beaches like The Bahamas 66.7 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (32)

This donkey skull was recovered in a Tang Dynasty noblewoman's tomb. The researchers determined that she played donkey polo and was buried with her donkeys so that she may continue her favorite sport in the afterlife.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (33)

Hundreds of mammoth bones found at a site in Russia were once used by hunter-gatherers to build a massive structure 25,000 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (34)

A fossil of an ancient rudist clam called Torreites sanchezi revealed that Earth's days lasted 23.5 hours 70 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (35)

This is an artist's impression of dinosaurs on prehistoric mudflat in Scotland, based on varied dinosaur footprints recovered on the Isle of Skye.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (36)

A new study suggests that ostrich eggshell beads have been used to cement relationships in Africa for more than 30,000 years.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (37)

This rock lined the seafloor roughly 3.2 billion years ago, providing evidence that Earth may have been a 'waterworld' in its ancient past.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (38)

These stone tools were found at the Dhaba site in India, showing that hom*o sapiens survived a massive volcanic eruption 74,000 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (39)

The remains of 48 people who were buried in a 14th century Black Death mass grave were found in England's Lincolnshire countryside.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (40)

The articulated remains of a Neanderthal have been found in Shanidar Cave, representing the first discovery of its kind in 20 years.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (41)

A rare disease that still affects humans today has been found in the fossilized vertabra of a duck-billed dinosaur that roamed the Earth at least 66 million years ago.

Venezuelan Palaeontologist Rodolfo Sánchez is shown next to a male carapace of the giant turtle Stupendemys geographicus, for scale.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (43)

This artist's illustration shows the newly discovered Tyrannosaurus rex relative, Thanatotheristes degrootorum.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (44)

The newly discovered species Allosaurus jimmadseni represents the earliest Allosaurus known. It was a fearsome predator that lived during the Late Jurassic Period millions of years before Tyrannosaurus rex.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (45)

Remains found in ancient Herculaneum boat houses revealed that people trying to flee the eruption of Mount Vesuvius slowly suffocated as volcanic clouds overtook the town.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (46)

The Wulong bohaiensis fossil found in China's Jehol Province shows some early, intriguing aspects that relate to both birds and dinosaurs.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (47)

Shell tools were recovered from an Italian cave that show Neanderthals combed beaches and dove in the ocean to retrieve a specific type of clam shell to use as tools.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (48)

A closer look at the Heslington brain, which is considered to be Britain's oldest brain and belonged to a man who lived 2,600 years ago. Amazingly, the soft tissue was not artificially preserved.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (49)

Researchers from Russia's RAS Institute of Archeology excavated the burial sites of four women, who were buried with battle equipment in southwestern Russia and believed to be Amazon warrior women. The oldest woman found in the graves bore a unique, rare ceremonial headdress.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (50)

Teen Tyrannosaurus rex were fleet-footed with knife-like teeth, serving as mid-sized carnivores before they grew into giant bone-crushing adults.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (51)

A hom*o erectus skull cap discovered in Central Java, Indonesia reveals how long they lived and when the first human species to walk upright died out.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (52)

This is an artistic reconstruction of Lola, a young girl who lived 5,700 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (53)

Part of the scene depicted in the world's oldest cave art, which shows half-animal, half-human hybrids hunting pigs and buffalo.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (54)

An ancient Egyptian head cone was first found with the remains of a young woman buried in one of Amarna's graves.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (55)

A lice-like insect was trapped in amber crawling and munching on a dinosaur feather.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (56)

Newly discovered penguin species Kupoupou stilwelli lived after the dinosaurs went extinct and acts as a missing link between giant extinct penguins and the modern penguins in Antarctica today.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (57)

This illustration compares the jaws and teeth of two predatory dinosaurs, Allosaurus (left) and Majungasaurus (right).

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (58)

This is an artist's illustration of Najash rionegrina in the dunes of the Kokorkom desert that extended across Northern Patagonia during the Late Cretaceous period. The snake is coiled around with its hindlimbs on top of the remains of a jaw bone from a small charcharodontosaurid dinosaur.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (59)

University of South Carolina archaelogist Christopher Moore (second from right) and colleagues collect core samples from White Pond near Elgin, South Carolina, to look for evidence of an impact from an asteroid or comet that may have caused the extinction of large ice-age animals such as sabre-tooth cats and giant sloths and mastodons.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (60)

Core samples from White Pond near Elgin, South Carolina, show evidence of platinum spikes and soot indicative of an impact from an asteroid or comet.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (61)

The Sosnogorsk lagoon as it likely appeared 372 million years ago just before a deadly storm, according to an artist's rendering. The newly discovered tetrapod can be seen in the left side of the image below the surface.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (62)

Bronze goods recovered from a river in northern Germany indicate an ancient toolkit of a Bronze Age warrior.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (63)

Mold pigs are a newly discovered family, genus and species of microinvertebrates that lived 30 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (64)

Ferrodraco lentoni was a pterosaur, or "flying lizard," that lived among dinosaurs 96 million years ago. The fossil was found in Australia.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (65)

These Late Bronze Age feeding vessels were likely used for infants drinking animal milk.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (66)

This is the first depiction of what mysterious ancient humans called Denisovans, a sister group to Neanderthals, looked like. This image shows a young female Denisovan, reconstructed based on DNA methylation maps. The art was created by Maayan Harel.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (67)

Researchers found a fossil of one of the oldest bird species in New Zealand. While its descendants were giant seafaring birds, this smaller ancestor likely flew over shorter ranges.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (68)

A painting shows the new species of giant salamander called Andrias sligoi, the largest amphibian in the world.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (69)

After her discovery in 2013, Victoria's 66-million-year-old, fossilized skeleton was restored bone by bone. She's the second most complete T. rex fossil on record.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (70)

An artist's illustration shows how different an ancient "short-faced" kangaroo called Simosthenurus occidentalis looked, as opposed to modern kangaroos. Its skull more closely resembles a koala.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (71)

An artist's illustration of Cryodrakon boreas, one of the largest flying animals that ever lived during the Cretaceous period. Although researchers don't know the color of Cryodrakon's plumage, the colors shown here honor Canada, where the fossil was found.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (72)

A graphic thermal image of a T. rex with its dorsotemporal fenestra glowing on the skull.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (73)

A complete skull belong to an early human ancestor has been recovered in Ethiopia. A composite of the 3.8 million-year-old cranium of Australopithecus anamensis is seen here alongside a facial reconstruction.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (74)

The remains inside grave IIIN199, found under Prague Castle in 1928, belong to a man from the 10th century. His identity has been the subject of great debate for years.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (75)

Vertebrae fossils of a previously undiscovered type of stegosaurus were found in Morocco. Researchers say they represent the oldest stegosaurus found.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (76)

The La Chapelle-aux-Saints Neanderthal skull shows signs of external auditory exostoses, known as "surfer's ear" growths, in the left canal.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (77)

The Fincha Habera rock shelter in the Ethiopian Bale Mountains served as a residence for prehistoric hunter-gatherers.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (78)

The world's largest parrot, Heracles inexpectatus, lived 19 million years ago in New Zealand. It was over 3 feet tall and weighed more than 15 pounds.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (79)

Saber-toothed cats, dire wolves and coyotes had different hunting patterns according to a new study of predator fossils found in the La Brea Tar Pits.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (80)

Researchers found 83 tiny glassy spheres inside fossil clams from a Florida quarry. Testing suggests that they are evidence of one or more undocumented meteorite impacts in Florida's distant past.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (81)

This primitive dinosaur had a wide W-shaped jaw and a solid bony crest resembling a humped nose.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (82)

An illustration of a Microraptor as it swallows a lizard whole during the Cretaceous period. The well-preserved fossils of the Microraptor and the lizard were both found, leading to the discovery that the lizard was a previously unknown species.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (83)

The back of a skull found in a Grecian cave has been dated to 210,000 years ago. Known as Apidima 1, right, researchers were able to scan and re-create it (middle and left). The rounded shape of Apidima 1 is a unique feature of modern humans and contrasts sharply with Neanderthals and their ancestors.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (84)

A 33,000-year-old human skull shows evidence of being struck with a club-like object. The right side of the man's head has a large depressed fracture.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (85)

The recently discovered fossilized femur of an ancient giant bird revealed that it weighed nearly as much as an adult polar bear and could reach 11½ feet tall. It lived between 1.5 million and 2 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (86)

This jawbone belonged to a Neanderthal girl who lived 120,000 years ago. It was found in Scladina Cave in Belgium.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (87)

This is an artist's illustration of the newly discovered dinosaur species Fostoria dhimbangunmal.

Radiocarbon dating has revealed that this Iron Age wooden shield was made between 395 and 255 BC.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (89)

The incredibly well-preserved fossil of a 3 million-year-old extinct species of field mouse, found in Germany, which was less than 3 inches long, was found to have red pigment in its fur.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (90)

A mass grave dated to 5,000 years ago in Poland contains 15 people who were all from the same extended family.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (91)

This is an artist's impression of the Ambopteryx longibrachium, one of only two dinosaurs known to have membranous wings. The dinosaur's fossilized remains were found in Liaoning, in northeast China, in 2017.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (92)

Reconstruction of a small tyrannosauroid Suskityrannus hazelae from the Late Cretaceous.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (93)

Researchers have been studying Archaeopteryx fossils for 150 years, but new X-ray data reveal that the bird-like dinosaur may have been an "active flyer."

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (94)

A 160,000-year-old Denisovan jawbone found in a cave on the Tibetan Plateau is the first evidence of the presence of this ancient human group outside the Denisova Cave in Siberia.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (95)

An artist's illustration of Simbakubwa kutokaafrika, a gigantic carnivore that lived 23 million years ago. It is known from fossils of most of its jaw, portions of its skull and parts of its skeleton. It was a hyaenodont, a now-extinct group of mammalian carnivores, that was larger than a modern-day polar bear.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (96)

The right upper teeth of the newly discovered species hom*o luzonensis. The teeth are smaller and more simplified than those belonging to other hom*o species.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (97)

The towering and battle-scarred "Scotty" is the world's largest Tyrannosaurus rex and the largest dinosaur skeleton ever found in Canada.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (98)

Researchers discovered unknown species at the Qingjiang fossil site on the bank of the Danshui River, near its junction with the Qingjiang River in Hubei Province, China.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (99)

During a study of the ancient Iberian population, the remains of a man and woman buried together at a Spanish Bronze Age site called Castillejo de Bonete showed that the woman was a local and the man's most recent ancestors had come from central Europe.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (100)

Durrington Walls is a Late Neolithic henge site in Wiltshire. Pig bones recovered at the site revealed that people and livestock traveled hundreds of miles for feasting and celebration.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (101)

An artist's impression of a Galleonosaurus dorisae herd on a riverbank in the Australian-Antarctic rift valley during the Early Cretaceous, 125 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (102)

The remains of 137 children and 200 llamas were found in Peru in an area that was once part of the Chimú state culture, which was at the peak of power during the 15th century. The children and llamas might have been sacrificed due to flooding.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (103)

The tooth of an extinct giant ground sloth that lived in Belize 27,000 years ago revealed that the area was arid, rather than the jungle that it is today.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (104)

An artist's illustration of what the small tyrannosaur Moros intrepidus would have looked like 96 million years ago. These small predators would eventually become Tyrannosaurus rex.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (105)

Examples of tools manufactured from monkey bones and teeth recovered from the Late Pleistocene layers of Fa-Hien Lena Cave in Sri Lanka show that early humans used sophisticated techniques to hunt monkeys and squirrels.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (106)

Footprints thought to belong to Neanderthals have been found in the Catalan Bay Sand Dune.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (107)

Two of the fossil specimens discovered in Korea had reflective eyes, a feature still apparent under light.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (108)

An artist's illustration of Mnyamawamtuka moyowamkia, a long-necked titanosaur from the middle Cretaceous period recently found in Tanzania. Its tail vertebra has a unique heart shape, which contributed to its name. In Swahili, the name translates to "animal of the Mtuka with a heart-shaped tail."

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (109)

The oldest evidence of mobility is 2.1 billion years old and was found in Gabon. The tubes, discovered in black shale, are filled with pyrite crystals generated by the transformation of biological tissue by bacteria, found in layers of clay minerals.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (110)

Researchers recently studied climate change in Greenland as it happened during the time of the Vikings. By using lake sediment cores, they discovered it was actually warmer than previously believed. They studied at several sites, including a 21st-century reproduction of Thjodhild's church on Erik the Red's estate, known as Brattahlíð, in present day Qassiarsuk, Greenland.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (111)

This is an artist's illustration of Antarctica, 250 million years ago. The newly discovered fossil of a dinosaur relative, Antarctanax shackletoni, revealed that reptiles lived among the diverse wildlife in Antarctica after the mass extinction.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (112)

Bone points and pierced teeth found in Denisova Cave were dated to the early Upper Paleolithic. A new study establishes the timeline of the cave, and it sheltered the first known humans as early as 300,000 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (113)

This artist's illustration shows a marine reptile similar to a platypus hunting at dusk. This duckbilled animal was the first reptile to have unusually small eyes that most likely required it to use other senses, such as the tactile sense of its duckbill, to hunt for prey.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (114)

Although it's hard to spot, researchers found flecks of lapis lazuli pigment, called ultramarine, in the dental plaque on the lower jaw of a medieval woman.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (115)

A Neanderthal fossil, left, and a modern human skeleton. Neanderthals have commonly be considered to show high incidences of trauma compared with modern humans, but a new study reveals that head trauma was consistent for both.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (116)

The world's oldest figurative artwork from Borneo has been dated to 40,000 years ago, when humans were living on what's now known as Earth's third-largest island.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (117)

A 250,000-year-old Neanderthal child's tooth contains an unprecedented record of the seasons of birth, nursing, illness and lead exposures over the first three years of its life.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (118)

An artist's illustration shows giant nocturnal elephant birds foraging in the ancient forests of Madagascar at night. A new study suggests that the now-extinct birds were nocturnal and blind.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (119)

Kebara 2 is the most complete Neanderthal fossil recovered to date. It was uncovered in Israel's Kebara Cave, where other Neanderthal remains have been found.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (120)

The world's oldest intact shipwreck was found by a research team in the Black Sea. It's a Greek trading vessel that was dated to 400 BC. The ship was surveyed and digitally mapped by two remote underwater vehicles.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (121)

This fossil represents a new piranha-like fish from the Jurassic period with sharp, pointed teeth. It probably fed on the fins of other fishes.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (122)

The fossil skull of the young Diplodocus known as Andrew, held by Cary Woodruff, director of paleontology at the Great Plains Dinosaur Museum.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (123)

Two small bones from the Ciemna Cave in Poland are the oldest human remains found in the country. The condition of the bones also suggests that the child was eaten by a large bird.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (124)

This artist's illustration shows the newly discovered dinosaur species Ledumahadi mafube foraging in the Early Jurassic of South Africa. Heterodontosaurus,another South African dinosaur, can also be seen in the foreground.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (125)

A 73,000-year-old red cross-hatch pattern was drawn on a flake of silicrete, which forms when sand and gravel cement together, and found in a cave in South Africa.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (126)

A suite of Middle Neolithic pottery including typical Danilo ware, figulina and rhyta that was used to hold meat, milk, cheese and yogurt.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (127)

These four dinosaurs showcase the evolution of alvarezsaurs. From left, Haplocheirus, Xiyunykus, Bannykus and Shuvuuia reveal the lengthening of the jaws, reduction of teeth and changes in the hand and arm.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (128)

Eorhynchochelys sinensis is an early turtle that lived 228 million years ago. It had a toothless beak, but no shell.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (129)

The leg bones of a 7-year-old, recovered from an ancient Roman cemetery, show bending and deformities associated with rickets.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (130)

The famed Easter Island statues, called moai, were originally full-body figures that have been partially covered over the passage of time. They represent important Rapa Nui ancestors and were carved after a population was established on the island 900 years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (131)

Researchers stand at the excavation site of Aubrey Hole 7, where cremated human remains were recovered at Stonehenge to be studied. New research suggests that 40% of 25 individuals buried at Stonehenge weren't from there -- but they possibly transported stones from west Wales and helped build it.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (132)

The fossil of the newly discovered armored dinosaur Akainacephalus johnsoni was found in southern Utah.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (133)

The foot is one part of a partial skeleton of a 3.32 million-year-old skeleton of an Australopithecus afarensis child dubbed Selam.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (134)

The asteroid impact that caused dinosaurs to go extinct also destroyed global forests, according to a new study. This illustration shows one of the few ground-dwelling birds that survived the toxic environment and mass extinction.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (135)

The remains of a butchered rhinoceros are helping researchers to date when early humans reached the Philippines. They found a 75% complete skeleton of a rhinoceros that was clearly butchered, with 13 of its bones displaying cut marks and areas where bone was struck to release marrow, at the Kalinga archaeological site on the island of Luzon.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (136)

This is just one of 26 individuals found at the site of a fifth-century massacre on the Swedish island of Öland. This adolescent was found lying on his side, which suggests a slower death. Other skeletons found in the homes and streets of the ringfort at Sandby borg show signs of sudden death by blows to the head.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (137)

The skeleton of a young woman and her fetus were found in a brick coffin dated to medieval Italy. Her skull shows an example of neurosurgery, and her child was extruded after death in a rare "coffin birth."

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (138)

This portion of a whale skull was found at the Calaveras Dam construction site in California, along with at least 19 others. Some of the pieces measure 3 feet long.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (139)

A Stone Age cow skull shows trepanation, a hole in the cranium that was created by humans as as surgical intervention or experiment.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (140)

On the left is a fossilized skull of our hominin ancestor hom*o heidelbergensis, who lived 200,000 to 600,000 years ago. On the right is a modern human skull. Hominins had pronounced brow ridges, but modern humans evolved mobile eyebrows as their face shape became smaller.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (141)

On the left is a 13,000-year-old footprint as found in the sediment on Calvert Island, off the Canadian Pacific coast. On the right is a digitally enhanced image, showing details of the footprint.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (142)

A central platform at Star Carr in North Yorkshire, England, was excavated by a research team studying past climate change events at the Middle Stone Age site. The Star Carr site is home to the oldest evidence of carpentry in Europe and of built structures in Britain.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (143)

This wall with paintings is in the La Pasiega Cave in Spain. The ladder shape of red horizontal and vertical lines is more than 64,000 years old and was made by Neanderthals.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (144)

These perforated shells were found in Spain's Cueva de los Aviones sea cave and date to between 115,000 and 120,000 years ago. Researchers believe these served as body ornamentation for Neanderthals.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (145)

The earliest modern human fossil ever found outside of Africa has been recovered in Israel. This suggests that modern humans left Africa at least 50,000 years earlier than previously believed. The upper jawbone, including several teeth, was recovered in a prehistoric cave site.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (146)

This is an excavated structure at the northern edge of the Grand Plaza at Teposcolula-Yucundaa in Oaxaca, Mexico. Researchers investigated a "pestilence" cemetery associated with a devastating 1545-1550 epidemic. New analysis suggests that salmonella caused a typhoid fever epidemic.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (147)

Standing about 4 feet tall, early human ancestor Paranthropus boisei had a small brain and a wide, dish-like face. It is most well-known for having big teeth and hefty chewing muscles.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (148)

A grand grave of a great Viking warrior excavated during the 1880s has been found to be that of a woman. She was also buried with a gaming board and pieces, hierarchically associated with officers to use for battle strategy and tactics. The drawing is a reconstruction of how the grave with the woman originally may have looked.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (149)

An illustration shows the dodo on Mauritius near the Mare aux Songes, where many dodo skeletons have been recovered.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (150)

A 5,000-year-old dog skull found in Germany underwent whole genome sequencing. It was found to be very similar to the genome of modern dogs, suggesting that all modern dogs are direct ancestors of the domesticated dogs that lived in the world's earliest farming communities in Europe.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (151)

Razanandrongobe sakalavae, or "Razana," was one of the top predators of the Jurassic period in Madagascar 170 million years ago. Although it looks different from modern-day crocodiles and had teeth similar to a T. rex's, Razana was not a dinosaur but a crocodile relative with a deep skull.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (152)

An artist's reconstruction shows Macrauchenia patachonica, which roamed South America thousands of years ago. Combining a range of odd characteristics from llamas and camels to rhinos and antelopes, Macrauchenia defied clarification until now and has been added to the tree of life. It belongs to a sister group of Perissodactyla, which includes horses, rhinos and tapirs.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (153)

This prosthetic device was made for a priest's daughter who had to have her right big toe amputated 3,000 years ago. This surprisingly lifelike toe was made to look natural by a skilled artisan who wanted to maintain the aesthetic as well as mobility during the Early Iron Age. It was designed to be worn with sandals, the footwear of choice at the time.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (154)

The oldest fossil remains of hom*o sapiens, dating back 300,000 years, were found at a site in Jebel Irhoud, Morocco. This is 100,000 years older than previously discovered fossils of hom*o sapiens that have been securely dated. The fossils, including a partial skull and a lower jaw, belong to five different individuals including three young adults, an adolescent and a child estimated to be 8 years old.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (155)

Nodosaurs were herbivores who walked on four legs and were covered in tank-like armor and dotted with spikes for protection. But this recently unveiled 110 million-year-old fossil is the most well-preserved of the armored dinosaurs ever unearthed.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (156)

Microfossils found in China have revealed what could be our earliest known ancestor on the tree of life. Saccorhytus was a tiny, bag-like sea creature that lived 540 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (157)

In 2016, researchers discovered ancient collagen and protein remains preserved in the ribs of a dinosaur that walked the Earth 195 million years ago.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (158)

By studying the skeleton of this medieval pilgrim, researchers have been able to genotype leprosy. They also discovered that leprosy-causing bacteria have changed little over hundreds of years, possibly explaining the decline in the disease after it peaked in medieval Europe as humans developed resistance.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (159)

The discovery of a species that lived 6.6 million years ago in southwestern China suggests that ancient otters had "wolf-like" proportions, and weighed roughly 100 Ibs. The creature -- whose skull was excavated in Yunnan province -- would have been twice the size of today's otters.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (160)

The tail of a 99-million-year-old dinosaur was found entombed in amber in 2016, an unprecedented discovery that has blown away scientists. The amber adds to fossil evidence that many dinosaurs sported feathers rather than scales.

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (161)

For the first time, researchers discovered genomic evidence of malaria in 2,000-year-old human remains from the Roman Empire. The discovery was made in 2016.

Ancient finds

CNN

When dinosaurs walked the Earth, days on our planet were a little bit shorter than the full 24 hours we know today.

Earth turned more quickly, meaning that a day lasted about 23.5 hours and a year equated to 372 days, according to a new study.

Researchers discovered this fact from a surprising resource: ancient shells, dated to the Late Cretaceous period 70 million years ago.

International Gemini Observatory image of 2020 CD3 (center, point source) obtained with the 8-meter Gemini North telescope on Hawaii's Maunakea. The image combines three images each obtained using different filters to produce this color composite. 2020 CD3 remains stationary in the image since it was being tracked by the telescope as it appears to move relative to the background stars, which appear trailed due to the object's motion.Credit: The international Gemini Observatory/NSF's National Optical-Infrared Astronomy Research Laboratory/AURA/G. Fedorets The international Gemini Observatory/NSF's National Optical-Infrared Astronomy Research Laboratory Related article Earth has a new mini-moon -- but it's only temporary

The fossilized mollusk shell belonged to a group called rudist clams, which grew quickly and recorded their lives in daily growth rings visible in the shells. These specific clams were known as Torreites sanchezi and rudist means that they have two shells, with a hinge connecting them.

Laser sampling produced slices of the shells, allowing the researchers to get an accurate count of the rings. That let them know how many days there were in a year, allowing for the breakdown of how long a day would be.

The study published this week in the journal Paleooceanography and Paleoclimatology, which is published by the America Geophysical Union.

“We have about four to five data points per day, and this is something that you almost never get in geological history. We can basically look at a day 70 million years ago. It’s pretty amazing,” said Niels de Winter, lead study author and analytical geochemist at Vrije Universiteit Brussel.

We’ve long known that an Earth day lasts 24 hours, and that remains constant because Earth’s trip around the sun doesn’t vary.

Dr. David A. Kring/Center for Lunar Science and Exploration Related article Earth's oldest rock was found by Apollo 14 astronauts -- on the moon

However, the number of days that make an Earth year have shifted and shortened because days have grown longer. That is thanks to the moon’s gravity, which draws on ocean’s tides and slows Earth’s rate of rotation.

Meanwhile, as the moon tugs on Earth, our natural satellite distances itself about 1.5 inches per year from Earth.

The ancient shell also contained information about the environment the clams lived in. Shell data revealed that oceans during the Late Cretaceous 70 million years ago were much warmer than they are now, reaching 104 degrees Fahrenheit in the summer and above 86 degrees Fahrenheit in the winter.

The maximum temperature would have about reached the limit for mollusks like clams, the researchers said.

The Apollo program included 12 manned missions that launched in the late 1960s and early 70s. Three missions orbited the Earth: Apollo 7, 9 and Apollo-Soyuz. Two missions orbited the moon: Apollo 8 and 10. One made a lunar swingby: Apollo 13 -- a malfunction forced NASA to cancel the landing. Six missions landed on the moon: Apollo 11, 12, 14, 15, 16, and 17. NASA Related article Asteroid impacts on the Earth and moon have increased since the dinosaurs lived

But these clams enjoyed temperatures that were warmer than today’s oceans.

The particular clam they studied lived for more than nine years, situated in a shallow tropical seabed. Today, this is dry land in Oman. Rudist clams are unique looking, described in a release by AGU as resembling “tall pint glasses with lids shaped like bear claw pastries.”

Like oysters, the clams thrived in reef environments. And in their day, they acted like coral, building and growing together.

“Rudists are quite special bivalves. There’s nothing like it living today,” de Winter said. “In the Late Cretaceous especially, worldwide most of the reef builders are these bivalves. So they really took on the ecosystem building role that the corals have nowadays.”

The crescent Earth rises over the moon's horizon in this photograph taken from the Apollo 17 spacecraft in December 1972. NASA Related article New clues about how Earth got its moon

And they loved sunlight.

Their shells grew faster during the day in response to sunlight. The researchers believe this means that like modern giant clams, which are covered in algae, these clams were similarly supporting a symbiotic species.

But the clams were wiped out 66 million years ago, just like the dinosaurs.

The data collected from the shell helped the researchers piece together parts of Earth’s past, as well as the evolution of clams. In the future, the researchers hope to study older fossils and learn more about a day in the life of Earth’s distant past.

Ad Feedback

Ad Feedback

Ad Feedback

Ad Feedback

Ad Feedback

Ad Feedback

In Earth’s early history, a day was 23.5 hours and a year lasted 372 days | CNN (2024)
Top Articles
Latest Posts
Article information

Author: Dr. Pierre Goyette

Last Updated:

Views: 6052

Rating: 5 / 5 (50 voted)

Reviews: 81% of readers found this page helpful

Author information

Name: Dr. Pierre Goyette

Birthday: 1998-01-29

Address: Apt. 611 3357 Yong Plain, West Audra, IL 70053

Phone: +5819954278378

Job: Construction Director

Hobby: Embroidery, Creative writing, Shopping, Driving, Stand-up comedy, Coffee roasting, Scrapbooking

Introduction: My name is Dr. Pierre Goyette, I am a enchanting, powerful, jolly, rich, graceful, colorful, zany person who loves writing and wants to share my knowledge and understanding with you.