As we go about our daily lives, it's easy to forget that the places we find ourselves weren't always the way they are now. While people driving down Highway 163 in Utah's Monument Valley may be awestruck by the towering red rocks, they may not think about what those rocks signify — the floor of an ancient ocean. In some places, history is simply hidden by the passage of time.
In the summer of 2020, Ranger Naturalist Greg Francek suddenly noticed he was standing in the midst of an entire petrified forest. Looking further, he discovered the fossilized remains of some of its ancient inhabitants. It soon became clear that Francek had come across one of the most important fossil sites ever discovered in California.
To protect the site, its exact location has not been revealed beyond its location nestled somewhere near the base of the Sierra Nevada foothills.
One fossil, the another
Credit: Bureau of Land Management/Flickr
Francek was poking around the Mokelumne River Watershed east of San Francisco. He works for the East Bay Municipal Utility District (EBMUD), which has managed the land around the Pardee and Camanche reservoirs that supply water to 1.4 million people living in San Francisco's East Bay for about a century.
Francek's eye was caught by an anomalous shape in the dirt. Closer examination revealed it was a piece of fossilized wood. "I looked around the area further," he recalled in a statement to EBMUD, "and I found a second tree. And then a third and so on. After finding dozens of trees I realized that what I was looking at was the remains of a petrified forest."
A few weeks later, he says, "I located the first vertebrate fossils. What I didn't comprehend at the time was the amazing fact that I was looking at the bones of great beasts that had roamed this landscape millions of years ago."
Realizing he'd found something significant, Francek reached out to EBMUD, who contacted an environmental consulting firm, who in turn reached out to Chico State's Russell Shapiro, a professor of paleontology and stratigraphy in the Geological and Environmental Sciences Department. Soon, paleontologists and geologists poured into the site, where excavation is ongoing.
Shapiro explains the excitement. "What you hope to find is a tip of a tusk. Not only do we have the tip, but we have the entire thing. And it's just beautiful ivory. It's mind-blowing." He and his students are among those working the site. They describe the process in Chico State Today.
"This new find is highly significant for both the sheer volume and diversity of the fossils," Shapiro told EBMUD. "This was a profound juncture in time when land animals evolved as forestland shifted to grassland."
The great beasts of the petrified forest
Credit: Chico State Today
A wide variety of fossilized remains have been found in the watershed. There are the ancestors of elephants: mastodons and four-tusked gomphotheres. (The last mastodon fossils discovered in California were found in 1947 during construction of a pipeline in Contra Costa County.)
Researchers have also unearthed camel fossils (!) and a massive 400-pound salmon with spiked teeth. Add to the list tapirs, horses, tortoises, and even rhinoceroses. No other site comparable in diversity has ever been found in the Golden State. Shapiro describes the story the fossils tell:
"I can look out and picture a movie reel of the lands changing. Through the trees, I see one group of elephants peek out as another walks by, and then great horses come in."
According to EBMUD, experts hope to find answers to an assortment of intriguing questions as work progresses: "Why are all these fossils in this location? How did they die? What happened and when?"
Unfortunately, we'll have to wait. It will take years to complete the study of the site.
One of the oldest activities carried out by humans has been identified in a cave in South Africa. A team of geologists and archaeologists found evidence that our ancestors were making fire and tools in the Wonderwerk Cave in the country's Kalahari Desert some 1.8 million years ago.
A new study published in the journal Quaternary Science Reviews from researchers at the Hebrew University of Jerusalem and the University of Toronto proposes that Wonderwerk — which means "miracle" in Afrikaans — contains the oldest evidence of human activity discovered.
"We can now say with confidence that our human ancestors were making simple Oldowan stone tools inside the Wonderwerk Cave 1.8 million years ago," shared the study's lead author Professor Ron Shaar from Hebrew University.
Oldowan stone tools are the earliest type of tools that date as far back as 2.6 million years ago. An Oldowan tool, which was useful for chopping, was made by chipping flakes off of one stone by hitting it with another stone.
An Oldowan stone toolCredit: Wikimedia / Public domain
Professor Shaar explained that Wonderwerk is different from other ancient sites where tool shards have been found because it is a cave and not in the open air, where sample origins are harder to pinpoint and contamination is possible.
Studying the cave, the researchers were able to pinpoint the time over one million years ago when a shift from Oldowan tools to the earliest handaxes could be observed. Investigating deeper in the cave, the scientists also established that a purposeful use of fire could be dated to one million years back.
This is significant because examples of early fire use usually come from sites in the open air, where there is the possibility that they resulted from wildfires. The remnants of ancient fires in a cave — including burned bones, ash, and tools — contain clear clues as to their purpose.
To precisely date their discovery, the researchers relied on paleomagnetism and burial dating to measure magnetic signals from the remains hidden within a sedimentary rock layer that was 2.5 meters thick. Prehistoric clay particles that settled on the cave floor exhibit magnetization and can show the direction of the ancient earth's magnetic field. Knowing the dates of magnetic field reversals allowed the scientists to narrow down the date range of the cave layers.
The Kalahari desert Wonderwerk CaveCredit: Michael Chazan / Hebrew University of Jerusalem
Professor Ari Matmon of Hebrew University used another dating method to solidify their conclusions, focusing on isotopes within quartz particles in the sand that "have a built-in geological clock that starts ticking when they enter a cave." He elaborated that in their lab, the scientists were "able to measure the concentrations of specific isotopes in those particles and deduce how much time had passed since those grains of sand entered the cave."
Finding the exact dates of human activity in the Wonderwerk Cave could lead to a better understanding of human evolution in Africa as well as the way of life of our early ancestors.
As complex as modern humans can get, they still retain some features of the earliest animals on Earth. According to new research, we are not as different as we might think from strange prehistoric organisms that didn't have any heads, arms, legs, or skeletons.
A study from UC Riverside identified 555-million-year-old oceanic creatures that share genes with humans and other contemporary animals.
The paper's co-author, UC Riverside geology professor Mary Droser, thinks the animals of the so-called Ediacaran era, which lasted from 571 million to 539 million years ago, were almost nothing like creatures of today.
"None of them had heads or skeletons. Many of them probably looked like three-dimensional bathmats on the sea floor, round discs that stuck up," said Droser in a press release. "These animals are so weird and so different, it's difficult to assign them to modern categories of living organisms just by looking at them, and it's not like we can extract their DNA — we can't."
Droser and her colleague Scott Evans of the National Museum of Natural History used fossil records to tie ancient ocean dwellers to the genetics of things alive now. They looked specifically at four animals as stand-ins for the 40+ Ediacaran era species scientists have been able to identify so far. Some of the creatures under discussion were as small as a few millimeters while others got almost a meter long. These included multicellular organisms like the sea-floor-scraping Kimberella, flat oval-shaped Dickinsonia, as well as the immobilized bottom-dweller Tribrachidium.
They also studied the Ikaria, animals that were recently discovered (by a team that also featured Evans and Droser). These jelly-bean-like creatures were no bigger than a grain of rice and represented the first bilaterians in the study. As the press release explains, bilaterians are symmetrical "organisms with a front, back, and openings at either end connected by a gut." If you're wondering, humans are bilateral. As are spiders and pigs. The scientists think the Ikaria might have had mouths, but those didn't get survive to be included in the fossil records.
Dickinsonia fossil, an animal from the Ediacaran era.
Credit: Mary Droser/UCR
How did the creatures get around without heads? They probably had the genetic parts that could govern heads as well as the requisite sensory organs. But their genes didn't yet work together in the complex way necessary for the heads and other sophisticated organs humans have to develop.
"The fact that we can say these genes were operating in something that's been extinct for half a billion years is fascinating to me," Evans pointed out.
The team plans to study the evolution of early animals further, investigating muscle development next.
Check out the study published in Proceedings of the Royal Society B.
Paleontologist Scott Evans looking for fossils in the Australian outback.
Credit: Droser Lab/UCR
Despite how many of them you can find at a museum, fossils are comparatively rare. They can only form when a plant or animal dies under certain conditions, and without them the remains are typically lost to time. These limitations mean that fossils depicting ancient creatures doing things (like fighting) are extremely difficult to find and are all the more important when discovered.
A new fossil showing a dinosaur's behavior has recently been discovered in Ganzhou, China giving insights into how the oviraptor tended to its eggs and perhaps even shedding light on its development.
Credit: Zhao Chuang / PNSO
The fossil depicts a large dinosaur sitting on a clutch of at least 24 eggs in a manner not unlike that of a bird. At least seven of the eggs contain fossilized embryos with the skeletons of the unhatched oviraptor. The apparently late level of development of these eggs combined with the lack of sediment between the bones and the eggs suggests that the oviraptor may have been incubating its nest when it died.
"Dinosaurs preserved on their nests are rare, and so are fossil embryos. This is the first time a non-avian dinosaur has been found, sitting on a nest of eggs that preserve embryos, in a single spectacular specimen," explains lead author Dr. Shundong Bi.
Co-author Dr. Matthew Lamanna also commented on how rare and exciting this find is:
"This kind of discovery, in essence fossilized behavior, is the rarest of the rare in dinosaurs. Though a few adult oviraptorids have been found on nests of their eggs before, no embryos have ever been found inside those eggs. In the new specimen, the babies were almost ready to hatch, which tells us beyond a doubt that this oviraptorid had tended its nest for quite a long time. This dinosaur was a caring parent that ultimately gave its life while nurturing its young."
The fossil in question, notice the open sections of the blue green eggs.
Credit: Shundong Bi
While this small pile of bones may not look impressive to you, it is a proverbial goldmine of information for paleontologists, shedding light on dinosaur behavior in ways that other fossils can't come close to.
The parent—it is not currently known if it was male or female—clearly had gastroliths, also called "stomach stones," in its abdominal region. Commonly consumed by animals to help grind foods they cannot fully process with their teeth, this find adds the oviraptor to the list of dinosaurs that used these stones as part of their digestion.
The different development levels seen in the fossilized embryos imply that the eggs might not all have hatched at the same time. This is a known occurrence for some birds, but before now, it was thought that this evolutionary development occurred too late for any dinosaur nest to feature it.
The researchers also examined oxygen isotopes in the remains and discovered that the eggs must have been kept at high temperatures typical of the incubation process. This further suggests that the parent was incubating the eggs as a bird does and keeping them at a necessary temperature rather than merely protecting them from an external threat, as a crocodile does.
While finding a dinosaur sitting on some eggs might not be the most exciting example of an activity-depicting fossil there is, the information that scientists can gather from it on the birth, life, and potentially the death of these animals will make this find an important one for years to come.
Neanderthals' image has undergone quite an upgrade in recent years. Where we once we thought of them as knuckle-dragging just-slightly-more-evolved apes, we now know that they were not so very unlike us. Evolutionarily more primitive, yes, but not by that much. They buried their dead, painted cave art, developed wooden tools, and even made string. We also know that their genetic traces remain in many modern humans. A new study from researchers at the University of Binghamton in New York State and Universidad de Alcalá in Spain pretty conclusively demonstrates they had the physical apparatus required for speaking and for understanding speech.
"This is one of the most important studies I have been involved in during my career," says co-author Ralph Quam. "The results are solid and clearly show the Neanderthals had the capacity to perceive and produce human speech. This is one of the very few current, ongoing research lines relying on fossil evidence to study the evolution of language, a notoriously tricky subject in anthropology."
The study is published in the journal Nature Ecology & Evolution.
Long-standing questions
Neanderthal reconstruction (right), 2014
Credit: Cesar Manso/Getty Images
"For decades, one of the central questions in human evolutionary studies has been whether the human form of communication, spoken language, was also present in any other species of human ancestor, especially the Neanderthals," says co-author Juan Luis Arsuaga.
The key to answering these questions, say the researchers, has to do first with Neanderthals' physical ability to hear in the frequency ranges typically involved in speech. In addition, while it's known that these ancient people had the physiological capacity for producing vowel sounds, the new research adds consonants to the Neanderthal repertoire, greatly expanding the possibilities for conveying a wide variety of meaning through the production of more types of sounds.
Neanderthal hearing
The authors made high-resolution CT scans of fossilized Neanderthal skulls—and skulls from some of their ancestors—found at UNESCO's archaeological site in northern Spain's Atapuerca Mountains. These scans served as the basis for virtual 3D models of the fossils' ear structures. Similar models of modern human ear structures were also created for comparison purposes.
Auditory bioengineering software assessed the hearing capabilities of the models. The software is capable of identifying sensitivity to frequencies up to 5 kHz, the midrange and low-midrange frequencies at which homo sapien speech primarily occurs. (We can hear much higher and lower frequencies, but that's where speech lies.)
Of particular importance is the "occupied bandwidth," the frequency region of greatest sensitivity, and therefore the spectrum most capable of accommodating enough different audio signals to represent a multitude of meanings. The occupied bandwidth is considered a critical requirement for speech since being able to produce and hear many different sounds—and understand their many different meanings—is the cornerstone of efficient communication.
Compared to their ancestors, the Neanderthal models turned out to have better hearing in the 4-5 kHz range, making their hearing more comparable to our own. In addition, the Neanderthals were found to have a wider occupied bandwidth than their predecessors, again more closely resembling modern humans.
Lead author of the study Mercedes Conde-Valverde says, "This really is the key. The presence of similar hearing abilities, particularly the bandwidth, demonstrates that the Neanderthals possessed a communication system that was as complex and efficient as modern human speech."
Consonants
Credit: sakura/Adobe Stock/Big Think
The study also suggests that Neanderthal vocalization were more advanced than previously thought. Says Quam: "Most previous studies of Neanderthal speech capacities focused on their ability to produce the main vowels in English spoken language."
However, he says, "One of the other interesting results from the study was the suggestion that Neanderthal speech likely included an increased use of consonants."
This is important, since "the use of consonants is a way to include more information in the vocal signal and it also separates human speech and language from the communication patterns in nearly all other primates. The fact that our study picked up on this is a really interesting aspect of the research and is a novel suggestion regarding the linguistic capacities in our fossil ancestors."
Bottom line
The study concludes that Neanderthals had the physiological hardware to produce a complex range of vocalizations, and the ability to understand them through ear structures not very unlike our own. This fits neatly with other recent insights as to the sophistication of the Neanderthals, a people who now seem to have been developing an expansive set of advanced capabilities simultaneously.
The authors of the study have been investigating the Neanderthals for almost 20 years, and others have been at it even longer. The work continues, and the study's publication marks a significant milestone in the much longer journey.
"These results are particularly gratifying," says co-author Ignacio Martinez. "We believe, after more than a century of research into this question, that we have provided a conclusive answer to the question of Neanderthal speech capacities."
