https://www.sciencealert.com/smallest-known-species-of-human-may-have-had-an-even-small...

"'This very rare specimen confirms our hypothesis that the ancestors of Homo floresiensis were extremely small in body size; however, it is now apparent from the tiny proportions of this limb bone that the early progenitors of the 'Hobbit' were even smaller than we had previously thought," Brumm says.

"Two notably tiny teeth – one from an adult and one from a child – were also found at the Mata Menge site during subsequent excavations in 2015 and 2016. The archeologists think their shape suggests H. floresiensis is descended from a Javan population of Homo erectus, challenging hypotheses suggesting the small human might have split away from a more ancestral African species.

"'The evolutionary history of the Flores hominins is still largely unknown," says Brumm.

"'He says the fossils suggest this species of human "did indeed begin when a group of the early Asian hominins known as Homo erectus somehow became isolated on this remote Indonesian island, perhaps one million years ago, and underwent a dramatic body size reduction over time".

"While modern inhabitants of the Indonesian highlands, the Rampasasa, are also small in size, a 2018 genetic study showed no evidence of a direct relationship to H. floresiensis.
(my bold)

"There may even be benefits favoring small-statured humans in this particular environment similar to those that benefit many island-bound animals of reduced size, leading to the tiny trait evolving multiple times.

Comment: note my bold. If the Rampasasa are H. sapiens what are the Hobbits? Are they so mutated their DNA is really different andv hides a relationship?

https://www.usnews.com/news/news/articles/2024-08-06/fossils-suggest-even-smaller-hobbi...

"WASHINGTON (AP) — Twenty years ago on an Indonesian island, scientists discovered fossils of an early human species that stood at about 3 1/2 feet (1.07 meters) tall — earning them the nickname “hobbits.”

"Now a new study suggests ancestors of the hobbits were even slightly shorter.

“'We did not expect that we would find smaller individuals from such an old site,” study co-author Yousuke Kaifu of the University of Tokyo said in an email.

"The original hobbit fossils date back to between 60,000 and 100,000 years ago. The new fossils were excavated at a site called Mata Menge, about 45 miles from the cave where the first hobbit remains were uncovered.

"In 2016, researchers suspected the earlier relatives could be shorter than the hobbits after studying a jawbone and teeth collected from the new site. Further analysis of a tiny arm bone fragment and teeth suggests the ancestors were a mere 2.4 inches (6 centimeters) shorter and existed 700,000 years ago.

“'They’ve convincingly shown that these were very small individuals,” said Dean Falk, an evolutionary anthropologist at Florida State University who was not involved with the research.

***

"Researchers have debated how the hobbits – named Homo floresiensis after the remote Indonesian island of Flores – evolved to be so small and where they fall in the human evolutionary story. They're thought to be among the last early human species to go extinct.

"Scientists don't yet know whether the hobbits shrank from an earlier, taller human species called Homo erectus that lived in the area, or from an even more primitive human predecessor. More research – and fossils – are needed to pin down the hobbits’ place in human evolution, said Matt Tocheri, an anthropologist at Canada's Lakehead University."

Comment: they are a true mystery. Currently we have pigmy tribes. Maybe they are not so unusual, but they are not as small as the Hobbits

https://en.wikipedia.org/wiki/African_Pygmies

https://www.science.org/content/article/ancient-human-relative-really-bury-dead?utm_sou...

"A little over a year ago, paleoanthropologist Lee Berger and his team made an extraordinary claim about a diminutive hominin, Homo naledi, whose fossils his team discovered a decade ago in the dark and twisting narrows of South Africa’s Rising Star Cave system. The researchers argued that despite having a brain about one-third the size of a modern human’s, H. naledi deliberately buried its dead about 250,000 years ago amid geometric designs carved deep in the cave.

***

"The initial eLife reviews were scathing. Now, a paper published in the peer-reviewed journal PaleoAnthropology late last month concludes there’s no evidence in the cave sediments that H. naledi intentionally buried its dead. “It’s a really exhaustive paper,” says Elizabeth Sawchuk, a bioarchaeologist with the Cleveland Museum of Natural History who studies ancient burials in Africa. “They assess all the evidence, which they find insufficient.”

"Some paleoanthropologists say the Berger team exploited eLife’s approach to raise the profile of unreviewed conclusions. “I don’t think anything has united the paleoanthropological community like this has, in saying, ‘This is not how you should do it,’” says Andy Herries, a paleoanthropologist and geoarchaeologist at La Trobe University who has worked at Rising Star Cave but wasn’t involved in the eLife preprints. “And we are a group of people that generally don’t agree on anything.”

***

"In 2015, deep inside the Dinaledi chamber in Rising Star Cave, Berger and colleagues found fragmented skeletons from multiple individuals partially erupting from the cave floor. The bones of some skeletons were arranged as in life, whereas others were scattered. Limestone walls nearby were etched in crisscrossing patterns that the authors ascribed to H. naledi artists, although critics later suggested the marks could have been made by natural processes or by more recent visitors to the cave.

"...in November 2023, a paper by a group including Herries and María Martinón-Torres of Spain’s National Research Center for Human Evolution (CENIEH), who helped develop the x-ray fluorescence-based technique, argued the Berger team hadn’t ruled out the possibility that the bones might have landed in the cave by natural means, such as washing in with flooding water.

***

"Foecke and colleagues note their criticism doesn’t imply H. naledi couldn’t have buried its dead—just that the evidence provided doesn’t support such a conclusion.

“'It is a very good critique,” Herries says.

***

"Herries fears public perceptions of H. naledi’s symbolic capabilities and behavioral complexity will forever be influenced by the Berger team’s initial publicity push. “It’s very difficult to walk ideas back once they’re out there.'”

Comment: Until the furious argument is settled, my guess is H. naledi did not bury the dead and are simply another early Homo species.

https://www.sciencealert.com/momentous-discovery-shows-neanderthals-could-produce-human...

"'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 notion that Neanderthals (Homo neanderthalis) were much more primitive than modern humans (Homo sapiens) is outdated, and in recent years a growing body of evidence demonstrates that they were much more intelligent than we once assumed. They developed technology, crafted tools, created art and held funerals for their dead.

"Whether they actually spoke with each other, however, has remained a mystery. Their complex behaviors seem to suggest that they would have had to be able to communicate, but some scientists have contended that only modern humans have ever had the mental capacity for complex linguistic processes.

***

"They took high-resolution CT scans of the skulls of five Neanderthals to create virtual 3D models of the ear structures. They also modeled the ear structures in Homo sapiens, and a much older fossil - the skull of a Sima de los Huesos hominin, also known as the Sima hominin, the ancestor of Neanderthals, dating back to around 430,000 years ago.

"A model of the hearing capacity of these structures from the field of auditory bioengineering was then employed to understand frequency range to which the ears were most sensitive, also known as the occupied bandwidth. For modern humans, the occupied bandwidth is the human vocal range.

"The team found that Neanderthals had better hearing in the 4 to 5 kilohertz range than the Sima ancestor, and that the Neanderthal occupied bandwidth was closer to that of modern humans than that of the Sima hominin. This optimization strongly suggests that Neanderthals needed to hear each other's voices.

***

"Interestingly, the occupied bandwidth of Neanderthals extended into frequencies above 3 kilohertz that are primarily involved in consonant production. This, the team noted, would distinguish Neanderthal vocalizations from the vowel-based vocalizations of non-human primates and other mammals.

""Most previous studies of Neanderthal speech capacities focused on their ability to produce the main vowels in English spoken language," Quam said.

"'However, we feel this emphasis is misplaced, 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."

"Having the anatomy capable of producing and hearing speech doesn't necessarily mean that Neanderthals had the cognitive ability to do so, the researchers cautioned. But, they point out, we have no evidence that the Sima hominins exhibited the complex symbolic behavior, such as funerals and art, that we've found associated with Neanderthals.

"This difference in behavior parallels the difference in hearing capacity between Neanderthals and Sima hominins, which, the researchers say, suggests a coevolution of complex behaviors and the ability to communicate vocally.

"'Our results," they wrote in their paper, "together with recent discoveries indicating symbolic behaviors in Neanderthals, reinforce the idea that they possessed a type of human language, one that was very different in its complexity and efficiency from any other oral communication system used by non-human organisms on the planet.'"

Comment: human language is thought to have begun between 50-70,000 years ago. Did the older Neanderthal species have language earlier? This is all based on skull/ear studies, which means they are assuming the characteristics of the larynx's function as well as labiodental production of 'f' and 'v' sounds. Friday, November 24, 2023, 16:12

https://www.science.org/content/article/ancient-switch-soft-food-gave-us-overbite-and-a...

"When humans switched to processed foods after the spread of agriculture, they put less wear and tear on their teeth. That changed the growth of their jaws, giving adults the overbites normal in children. Within a few thousand years, those slight overbites made it easy for people in farming cultures to fire off sounds like "f" and "v," opening a world of new words.

"The newly favored consonants, known as labiodentals, helped spur the diversification of languages in Europe and Asia at least 4000 years ago; they led to such changes as the replacement of the Proto-Indo-European patēr to Old English faeder about 1500 years ago, according to linguist and senior author Balthasar Bickel at the University of Zurich in Switzerland. The paper shows "that a cultural shift can change our biology in such a way that it affects our language," says evolutionary morphologist Noreen Von Cramon-Taubadel of the University at Buffalo, part of the State University of New York system, who was not part of the study.

"Postdocs Damián Blasi and Steven Moran in Bickel's lab set out to test an idea proposed by the late American linguist Charles Hockett. He noted in 1985 that the languages of hunter-gatherers lacked labiodentals, and conjectured that their diet was partly responsible: Chewing gritty, fibrous foods puts force on the growing jaw bone and wears down molars. In response, the lower jaw grows larger, and the molars erupt farther and drift forward on the protruding lower jaw, so that the upper and lower teeth align. That edge-to-edge bite makes it harder to push the upper jaw forward to touch the lower lip, which is required to pronounce labiodentals. But other linguists rejected the idea, and Blasi says he, Moran, and their colleagues "expected to prove Hockett wrong."

"First, the six researchers used computer modeling to show that with an overbite, producing labiodentals takes 29% less effort than with an edge-to-edge bite. Then, they scrutinized the world's languages and found that hunter-gatherer languages have only about one-fourth as many labiodentals as languages from farming societies. Finally, they looked at the relationships among languages, and found that labiodentals can spread quickly, so that the sounds could go from being rare to common in the 8000 years since the widespread adoption of agriculture and new food processing methods such as grinding grain into flour.

"Bickel suggests that as more adults developed overbites, they accidentally began to use "f" and "v" more. In ancient India and Rome, labiodentals may have been a mark of status, signaling a softer diet and wealth, he says. Those consonants also spread through other language groups; today, they appear in 76% of Indo-European languages.

***

"The findings also suggest our facility with f-words comes at a cost. As we lost our ancestral edge-to-edge bite, "we got new sounds but maybe it wasn't so great for us," Moran says. "Our lower jaws are shorter, we have impacted wisdom teeth, more crowding—and cavities.'"

Comment: This explains the origin of our overbite and how it relates to producing speech.

https://www.sciencedirect.com/science/article/abs/pii/S0047248423001434

No scientific evidence that Homo naledi buried their dead and produced rock art

***

"Here we will examine the evidence for the alleged burials and the purported rock art presented in the three reviewed pre-prints together with a consideration of the open reviews published alongside them. The peer reviews were unanimous in considering the evidence inadequate in its present form. Despite this, these versions remain available and communicated to the press and social media without yet integrating any of the referee's comments.

"Here we argue that the evidence presented so far is not compelling enough to support the deliberate burial of the dead by H. naledi nor that they made the purported engravings. Substantial additional documentation and scientific analyses are needed before we can rule out that natural agents and post-depositional processes are responsible for the accumulation of bodies/body parts and to prove the intentional excavation and filling of pits by H. naledi. Moreover, detailed analyses are needed to demonstrate that the so-called ‘engravings’ are indeed human-made marks and that, like the purported evidence of fire use, they can be securely linked to H. naledi. Our commentary also offers a brief insight on the state of the field regarding the importance of responsible social communication and the challenges brought by new models of scientific publication.

***

"There is no convincing scientific evidence to indicate that H. naledi buried their dead and produced rock art in the Rising Star Cave system based on the information thus far presented. As explained here, the investigators have not employed the wide range of scientific methods (e.g., chronology, taphonomy, sedimentology, micromorphology, geochemistry) designed to answer the questions posed nor applied the basic principles of archeothanatology to identify a deliberate burial."

Commentary from Evolution News: https://evolutionnews.org/2023/11/journal-rejects-claims-that-homo-naledi-buried-dead-m...

"The paper argues against intentional burial of the dead on the basis that burials usually involve articulated skeletons, but in this case “the hominin bones are not articulated but scattered.” They note that there is some limited articulation of some body parts but this can also occur in a natural death scenario. The “almost vertical position” of some of the skeletal remains is also very unlike what would be expected if someone was digging a grave for a body.

"Berger and his team had claimed that a stone tool was encased in rock near a skeleton, showing Homo naledi used tools. The paper argues that “it is not possible to rule out the strong likelihood that this stone object is a geofact” — that is, a natural rock feature (as opposed to an artifact, which is a stone carved by an intelligent agent). They point out that it’s made of “the same material as the cave walls,” and the faces would represent “natural fractures” or “erosion.” Because the rock remains encased in sediment, they argue no one can presently perform the kind of study needed to make a proper determination, and thus the Homo naledi team’s claims can’t be verified.

***

"They make clear that the evidence for fire use isn’t there:

"More importantly, no scientific evidence (e.g., Fourier-transform infrared spectroscopy, micromorphology, archaeomagnetism) has been presented to indicate the occurrence of in situ burnt material, let alone hearths. Previously acquired radiocarbon dates obtained by the site investigators on one of the apparent hearths resulted in very young dates (Lee Berger, unpublished data), questioning its association to H. naledi. Moreover, the occurrence of charcoal is also common in caves, including in South African landscapes, where there are frequent wildfires, so finding burned material in a cave setting does not automatically indicate anthropogenic activity.

"Many critics acknowledged that wall markings in the cave look like art, but they were uncertain about evidence linking the scrawls to Homo naledi. That is because the marks have not been dated. The markings might have been made much more recently, perhaps even by a human in very recent historic times. This paper affirms the criticism, but it also expresses a deeper skepticism about whether the markings are artificial at all. They write:

"[N]umerous examples of shallow cross hatched and patterned natural erosional lines can be found throughout the Malmani dolomite, the geological formation that hosts Rising Star Cave and all the other Plio-Pleistocene hominin fossils in the region.

***

"IFL science is a heavily pro-evolution outlet, so when they accuse Homo naledi’s promoters and the Netflix documentary of pushing “hype” and “Homo naledi-mania,” that is really saying something."

Comment: this shows how science solidifies its findings with critical reviews. I reported the original articles here when they were published and accepted the findings at that time. The rejection now must await further work by critics.

https://www.scientificamerican.com/article/this-small-brained-human-species-may-have-bu...

"Researchers working in the Rising Star cave system near Johannesburg, South Africa, report that they have found evidence that the small-brained fossil human species Homo naledi engaged in several sophisticated behaviors that were previously associated exclusively with large-brained hominins. Describing their findings in three preprint papers that were posted on the server bioRxiv on June 5 and will be published in the journal eLife, they contend that H. naledi, whose brain was around a third of the size of our own, used fire as a light source, went to great lengths to bury its dead and engraved designs that were probably symbolic in the rock walls of the cave system. The findings are preliminary, but if future research bears them out, scientists may need to rethink how we became human.

***

"The fossils revealed a hominin with an unexpected combination of old and new traits. It walked fully upright like modern humans do, and its hands were dexterous like ours. But its shoulders were built for climbing, and its teeth were shaped like those of earlier hominins in the genus Australopithecus, explains team member John Hawks of the University of Wisconsin–Madison. Most striking of all, H. naledi had a brain size of just 450 to 600 cubic centimeters. For comparison, H. sapiens brain size averages around 1,400 cubic centimeters. Berger and his team announced the discovery as a species new to science in 2015. Two years later they were able to establish the age of the fossils, dating them to between 335,000 and 236,000 years ago—surprisingly recent for a species with such a small brain and other primitive traits.

***

Berger and his collaborators argued, was that H. naledi individuals entered this subterranean cave system deliberately to deposit their dead. If that were the case, they must have used a light source—namely fire—to navigate Rising Star’s dark and treacherous tunnels, chutes and chambers. But mortuary behavior and control of fire have long been considered the exclusive purview of larger-brained hominins. Without any direct evidence of fire or deliberate interment of the bodies, the suggestion that H. naledi might have been surprisingly sophisticated, given its small brain size remained firmly in the realm of speculation.

"Subsequent work in the cave has materially strengthened that case. Berger and his colleagues report evidence for burials in two locations in Rising Star, the Dinaledi Chamber and the Hill Antechamber. H. naledi corpses were intentionally placed in pits that had been dug in the ground, and the bodies were then covered with dirt.

***

"Berger finally ventured into the heart of Rising Star. And that’s when he noticed soot on the ceiling and charcoal and bits of burned bone on the floor, which indicated that fire had been used in the cave. At the same time, team member Keneiloe Molopyane of the University of the Witwatersrand, who was excavating another part of the cave system known as the Dragon’s Back, found a hearth. “Almost every space within these burial chambers, adjacent chambers and even the hallways ... has evidence of fire,” Berger says.

"Berger also made another, arguably more astonishing discovery that day in Rising Star: designs carved in the cave walls. The engravings consist of isolated lines and geometric motifs, including crosses, squares, triangles, X’s, hash marks and scalariform, or ladderlike, shapes. The markings were deeply incised into dolomite rock in locations close to the burials in the Dinaledi Chamber and Hill Antechamber. Dolomite is a particularly hard rock that measures around 4.7 on the Mohs scale of mineral hardness—“about halfway to a diamond,” Berger says. That means the engravers would have had to put considerable effort into making these marks. The engraved surfaces also appear to have been smoothed with hammerstones and polished with dirt or sand, according to the researchers. And some engraved areas gleam with a residue that may be the result of the rock being repeatedly touched.

"If H. naledi, with its small brain, was burying its dead, using fire as a light source and creating engravings, then scientists may need to rethink the connection between brain size and behavior. We need to step back and try to understand “the social and community emotional dynamics that allow this kind of complex behavior without having this big, complex brain,” says team member Agustín Fuentes of Princeton University. Taking this perspective makes us think about human evolution in a new way, he adds, and reminds us that “we know a lot less than we thought we did.” (my bold)

Comment: the findings are so surprising there is much criticism I have not presented since time and research will sort it all out. My bold is a key issue. How many neurons re needed to act like a human? Think of what bird brains can do.

https://www.sciencealert.com/the-oldest-known-burial-site-in-the-world-was-not-made-by-...

"Led by renowned palaeoanthropologist Lee Berger, researchers said they discovered several specimens of Homo naledi – a tree-climbing, Stone Age hominid – buried about 30 meters (100 feet) underground in a cave system within the Cradle of Humankind, a UNESCO world heritage site near Johannesburg.​

"'These are the most ancient interments yet recorded in the hominin record, earlier than evidence of Homo sapiens interments by at least 100,000 years," the scientists wrote in a series of yet to be peer-reviewed.

"The findings challenge the current understanding of human evolution, as it is normally held that the development of bigger brains allowed for the performing of complex, "meaning-making" activities such as burying the dead.​

"The oldest burials previously unearthed, found in the Middle East and Africa, contained the remains of Homo sapiens – and were around 100,000 years old.​

"Those found in South Africa by Berger, whose previous announcements have been controversial, and his fellow researchers, date back to at least 200,000 BC.

"​Critically, they also belong to Homo naledi, a primitive species at the crossroads between apes and modern humans, which had brains about the size of oranges and stood about 1.5 meters (five feet) tall.

"With curved fingers and toes, tool-wielding hands and feet made for walking, the species discovered by Berger had already upended the notion that our evolutionary path was a straight line.

"The oval-shaped interments at the centre of the new studies were also found there during excavations started in 2018.​

"The holes, which researchers say evidence suggests were deliberately dug and then filled in to cover the bodies, contain at least five individuals.

"'These discoveries show that mortuary practices were not limited to H. sapiens or other hominins with large brain sizes," the researchers said.

"The burial site is not the only sign that Homo naledi was capable of complex emotional and cognitive behavior, they added.

"Engravings forming geometrical shapes, including a "rough hashtag figure", were also found on the apparently purposely smoothed surfaces of a cave pillar nearby.​

"'That would mean not only are humans not unique in the development of symbolic practices, but may not have even invented such behaviors," Berger told AFP in an interview."

Comment: An isolated group of pre-humans in South Africa. Part of a picture of Homo types sprouting up everywhere.

https://www.the-scientist.com/news-opinion/ancient-viral-dna-plays-a-role-in-human-dise...

"Remnants of ancient viral pandemics in the form of viral DNA sequences embedded in our genomes are still active in healthy people, according to new research my colleagues and I recently published.

*HERVs, or human endogenous retroviruses, make up around 8% of the human genome, left behind as a result of infections that humanity’s primate ancestors suffered millions of years ago. They became part of the human genome due to how they replicate.

***

"Viruses insert their genomes into their hosts in the form of a provirus. There are around 30 different kinds of human endogenous retroviruses in people today, amounting to over 60,000 proviruses in the human genome. They demonstrate the long history of the many pandemics humanity has been subjected to over the course of evolution. Scientists think these viruses once widely infected the population, since they have become fixed in not only the human genome but also in chimpanzee, gorilla and other primate genomes.

"Research from our lab and others has demonstrated that HERV genes are active in diseased tissue, such as tumors, as well as during human embryonic development. But how active HERV genes are in healthy tissue was still largely unknown.

"To answer this question, our lab decided to focus on one group of HERVs known as HML-2. This group is the most recently active of the HERVs, having gone extinct less than 5 million years ago. Even now, some of its proviruses within the human genome still retain the ability to make viral proteins.

***

"Whether the genetic remnants of human endogenous retroviruses can cause disease in people is still under study. Researchers have spotted viruslike particles from HML-2 in cancer cells, and the presence of HERV genetic material in diseased tissue has been associated with conditions such as Lou Gehrig’s disease, or amyotrophic lateral sclerosis, as well as multiple sclerosis and even schizophrenia.

***

"...our research also suggests that HERVs could even be beneficial to people. The most famous HERV embedded in human and animal genomes, syncytin, is a gene derived from an ancient retrovirus that plays an important role in the formation of the placenta. Pregnancy in all mammals is dependent on the virus-derived protein coded in this gene.

"Similarly, mice, cats and sheep also found a way to use endogenous retroviruses to protect themselves against the original ancient virus that created them. While these embedded viral genes are unable to use their host’s machinery to create a full virus, enough of their damaged pieces circulate in the body to interfere with the replication cycle of their ancestral virus if the host encounters it. Scientists theorize that one HERV may have played this protective role in people millions of years ago. Our study highlights a few more HERVs that could have been claimed or co-opted by the human body much more recently for this same purpose.

"Our research reveals a level of HERV activity in the human body that was previously unknown, raising as many questions as it answered.

"There is still much to learn about the ancient viruses that linger in the human genome, including whether their presence is beneficial and what mechanism drives their activity. Seeing if any of these genes are actually made into proteins will also be important.

"Answering these questions could reveal previously unknown functions for these ancient viral genes and better help researchers understand how the human body reacts to evolution alongside these vestiges of ancient pandemics.The Conversation."

Comment: obviously an early research discovery. We keep finding DNA is filled with mysterious activity, and the fact that HERV's still are active means they must be useful.

https://www.science.org/content/article/mysterious-ancient-humans-may-have-given-people...

"Researchers have known for a decade that living people in Papua New Guinea and other parts of Melanesia, a subregion of the southwest Pacific Ocean, inherited up to 5% of their DNA from Denisovans, ancient humans closely related to Neanderthals who arrived in Asia about 200,000 years ago. Scientists assume those variants benefited people in the past—perhaps by helping the modern humans better ward off local diseases—but they have wondered how that DNA might still be altering how people look, act, and feel today. It’s been difficult to detect the function of Neanderthal and Denisovan DNA in Melanesians, however, because scientists have analyzed so little genetic data from living humans in Papua New Guinea and other parts of Melanesia.

"The new study overcomes that problem by using genetic data from 56 individuals from Papua New Guinea that were recently analyzed for another paper, part of the Indonesian Genome Diversity Project. The researchers, mostly from Australia and New Guinea, compared those genomes with those of Denisovans from Denisova Cave in Siberia, as well as Neanderthals. They found the Papuans had inherited unusually high frequencies of 82,000 genetic variants known as single nucleotide polymorphisms, which arise from differences of a single base or letter in the genetic code—from Denisovans.

***

"In Papuans, the scientists found many Denisovan variants that were located near genes known to impact human immune responses to viruses and other pathogens, such as the flu and chikungunya. Next, they tested the function of eight Denisovan gene variants associated with the expression of proteins produced by two genes in particular, OAS2 and OAS3, “lymphoblastoid”—cell lines of B cells, a type of white blood cell that makes antibodies critical to the body’s immune response. Those cell lines were collected from Papuans by study co-author Christopher Kinipi, a Papuan physician and health services director at the University of Papua New Guinea.

"Two of the Denisovan genetic variants found in those Papuan cell lines lowered the transcription or production of proteins that regulate cytokines, part of the immune system’s defense against infections, reducing inflammation. This subdued inflammatory response could have helped Papuans weather a rash of new infections they would have encountered in the region.

***

"These findings dovetail with earlier work on the role of Neanderthal variants in living Europeans. Studies of both Neanderthal and Denisovan DNA in different populations are showing how mating with archaic humans—long-adapted to their regions—provided a rapid way for incoming modern humans to pick up beneficial genes, says computational biologist Janet Kelso of the Max Planck Institute for Evolutionary Anthropology. The study shows this sort of gene swap was “an important mechanism for how humans adapted quickly [to new challenges], specifically pathogens,” says human geneticist Luis Barreiro of the University of Chicago."

Comment: dhw has asked why so many pre-sapiens were evolved. Helping with immunity indicates one good reason. This fits my theory of a God who does not have, or need, full control over all circumstances. Rather than specifically infecting groups of people, letting them become infected at random still results in good immunity levels, especially if effective genes can be passed around in advance.

https://www.sciencedaily.com/releases/2021/02/210216144328.htm

"Last year, researchers showed that a major genetic risk factor for severe COVID-19 is inherited from Neandertals. Now the same researchers show that Neandertals also contributed a protective variant. Half of all people outside Africa carry a Neandertal gene variant that reduces the risk of needing intensive care for COVID-19 by 20 percent.

***

"A major genetic risk factor is located on chromosome 3 and dramatically increases the risk of respiratory failure and even death. Hugo Zeberg and Svante Pääbo at Karolinska Institutet and the Max Planck Institute for Evolutionary Anthropology discovered last year that this risk variant is inherited from Neandertals.

"Now the research duo shows that the Neandertals also contributed a protective variant to present-day people. They find that a region on chromosome 12 that reduces the risk of needing intensive care upon infection with the virus by 20 percent is inherited from Neandertals. The genes in this region are called OAS and regulate the activity of an enzyme that breaks down viral genomes, and the Neandertal variant of the enzyme seems to do this more efficiently.

***

"The study also shows that the protective variant from Neandertals has increased in frequency since the last Ice Age so that it is now carried by about half of all people outside Africa.

"'It is striking that this Neandertal gene variant has become so common in many parts of the world. This suggests that it has been favourable in the past," says Svante Pääbo, director at the Max Planck Institute for Evolutionary Anthropology. "It is also striking that two genetic variants inherited from Neandertals influence COVID-19 outcomes in opposite directions. Their immune system obviously influences us in both positive and negative ways today.'"

Comment: A little interbreeding helped us sapiens folks. This has been discussed before when it was found that Neanderthal genes help our general immunity. This is a more specific case. dhw asked in the past why God would produce so many varieties of hominin/homo types and this result offers a reason.

https://www.newscientist.com/article/2264793-worlds-oldest-painting-of-animals-discover...

"Stunning cave paintings discovered in Indonesia include what might be the oldest known depictions of animals on the planet, dating back at least 45,000 years.

"The paintings of three pigs, alongside several hand stencils, were discovered in the limestone cave of Leang Tedongnge on the Indonesian island of Sulawesi. Even local people were unaware of the cave sites’ existence until their discovery in 2017 by Adam Brumm at Griffith University, Australia, and his team.

“'I was struck dumb,” says Brumm. “It’s one of the most spectacular and well-preserved figurative animal paintings known from the whole region and it just immediately blew me away.”

"Sulawesi is known to contain some of the world’s oldest cave art, but the new paintings may predate all other examples so far discovered on the island.

***

“'It adds to the evidence that the first modern human cave art traditions did not arise in ice age Europe, as long assumed, but at an earlier point in the human journey,” says Brumm.

"Each of the three pigs is more than a metre long. The images were all painted using a red ochre pigment. They appear to be Sulawesi warty pigs (Sus celebensis), a short-legged wild boar that is endemic to the island and is characterised by its distinctive facial warts. “This species was of great importance to early hunter-gatherers in Sulawesi,” says Brumm.

***

"Paul Pettitt at Durham University, UK, agrees that the discovery adds to evidence of human presence in the islands of south-east Asia. Early humans presumably crossed these islands to reach Australia – perhaps as early as 65,000 years ago – after migrating out of Africa.

"But Pettitt says: “Given the insufficient amount of human fossils in the region at this time, we cannot, of course, rule out authorship by another human species, like the Neanderthals [that] were producing non-figurative art in Europe.'”

Comment: Look at the art. It is impressive.

QUOTE: "Indeed, the Denisovans lived for hundreds of thousands of years in territories where modern humans are today, and they survived for longer than our own species has existed. They were numerous and geographically diffuse enough to birth what is likely an entirely new species of human, and they and our ancestors managed to live in close proximity to each other for tens of thousands of years."

DAVID: After surviving so long, there should be fossils to help us understand.

dhw: There are, and new ones are being discovered all the time. And each new discovery adds further mystification to the hypothesis that your God’s purpose from the very beginning was to specially design H. sapiens.

Well, the one thing that is certainly true is that we are the only ones here with bits and pieces of their DNA which added to our prospects for healthier living. Not so silly after all. Everything we discover adds to knowledge of God's purposeful activities, but only if one has an open mind.

DAVID: After surviving so long, there should be fossils to help us understand.

There are, and new ones are being discovered all the time. And each new discovery adds further mystification to the hypothesis that your God’s purpose from the very beginning was to specially design H. sapiens.

http://blogs.discovermagazine.com/d-brief/2019/04/11/denisovan-indonesia-humans-new-spe...

"a new study using genetic data is offering an intriguing new look into the history of the Denisovans, revealing them as a people of far greater diversity, and reach, than ever before.
The now-extinct people that we call Denisovans actually consisted of three distinct groups of humans spread throughout Eurasia, the researchers say. And one of those groups might well even be considered its own species.

"recent work, including the sequencing of their genome, has begun to peel back the layers of mystery. The Denisovans, along with the Neanderthals, were part of a branch of humans that diverged from our own lineage somewhere between 500,000 and 700,000 years ago. They inhabited Eurasia for hundreds of thousands of years, reaching from Siberia far into tropical Indonesia, and they interbred with both Neanderthals and modern humans.

***

"Previous studies have shown that Southeast Asians — and Pacific Islanders in particular — have a greater proportion of Denisovan DNA than the rest of us. These researchers confirmed that finding, but the breadth of their data also allowed them to go a step further. Pairing their evidence with geographic and demographic data, they used the modern-day fragments of Denisovan DNA to reconstruct what those ancient populations actually looked like.

"The result is a trove of data on the ancient hominins, one that substantially deepens our understanding of their lives writ large. But the find is no lucky break — Denisovan DNA has been lurking in the genomes of Indonesians and others in Southeast Asia all along. Up until now, though, Western scientists hadn’t thought to look.

***

"In some modern Indonesians, scientists found not one, but two distinct Denisovan genomic signatures. What’s more, these two groups also looked different from the Denisovans previously found in Siberia, which they researchers say was another group altogether. For those of you keeping count, that adds up to three different kinds of Denisovans spread from Siberia to across the disparate islands of Indonesia.

"It’s a substantial expansion of Denisovans’ range. Whereas scientists published evidence proving they lived in just one small cave in 2010, we now know that Denisovans ranged across thousands of miles during their time on Earth. Being spread across so wide and area for so long probably played a role in the Denisovans’ eventual diversification.

"The three groups were bounded by two large geographical impediments: the Himalayas in the east, and the oceanic gaps between the islands that make up Indonesia today. As the researchers see it, one group of Denisovans would have lived in or around present day Siberia, Kazakhstan and in China just north of the Himalayas. And the remains from members of this group are likely what researchers found in 2010. But a different group of Denisovans lived in Southeast Asia, around present day Thailand and Vietnam. The third group called the islands of Indonesia home. Those two southern groups diverged from the Siberian Denisovans over 250,000 years ago. That’s before anatomically-modern humans even appeared.

***

"One of the groups that showed up in the Papuan’s genomes actually looked so genetically distinct that Cox says they should likely be considered an entirely new species. While the researchers cannot name a new species without actual fossil evidence, Cox says that, genetically, the group living in south-east Asia looked as different from the Denisovans in Siberia as it did from Neanderthals.

“'If we’re going to call Neanderthals and Denisovans by a unique name, which we do, then we should probably call this other group by another name,” he says.

"The concept of “species” among ancient hominins is a bit difficult to define — after all, they could often produce fertile offspring with each other, violating a common definition of a species. But, by the current nomenclature, these Denisovans would have been as distinct as other groups of hominins that we call species. If so, it would add yet another branch to the still-growing evolutionary tree of ancient humans.

"Finding the Denisovans spread across so much territory, and inhabiting such different environments, should also notch up our regard for Denisovans’ abilities, Cox says.
“They must have been able to do water crossings, so they must have had some sort of rafts or canoes. We know that they lived across a wide range of environments, from up in Siberia where it freezes during the winter all the way down to tropical rainforests,” he says. “So they must have been incredibly adaptive.”

"Indeed, the Denisovans lived for hundreds of thousands of years in territories where modern humans are today, and they survived for longer than our own species has existed. They were numerous and geographically diffuse enough to birth what is likely an entirely new species of human, and they and our ancestors managed to live in close proximity to each other for tens of thousands of years."

Comment: After surviving so long, there should be fossils to help us understand.

https://cosmosmagazine.com/palaeontology/new-fossil-human-relative-found-in-the-philipp...

"A handful of teeth and limestone-encrusted hand, foot and leg bones dug out of a cave in the Philippines have been given their own branch on the human family tree.

"The new species – Homo luzonensis – is described this week in the journal Nature, and is believed to have lived more than 50,000 years ago on Luzon, the largest island in the Philippines.

"The discovery marks the second time that a species of early human has been found on islands in Southeast Asia that are separated from both the Asian and Australian continental shelves by deep-water straights.

"The diminutive Homo floresiensis, discovered in 2004 on the Indonesian island of Flores, was the first.

"H. luzonensis is also a mix of old and new, packaged in what was probably a small body.

***

"Together, the features set H. luzonensis apart from anatomically modern humans, as well as other early human lineages including Homo erectus, which made it all the way to Java, on the edge of the Asian continental shelf.

“'This is a very important discovery,” says palaeoanthropologist Darren Curnoe from the University of New South Wales, in Australia, who was not involved in the study.

***

"The ancient features of both H. floresiensis and H. luzonensis suggest that hominids may have dispersed out of Africa more than two million years ago.

"Once they reached the islands of south-east Asia, they could have evolved into separate species on different islands, much as occurred with tortoises and other animals on the Galapagos Islands.

“'You could have hominin species on all the different large islands in the Philippines,” says Piper. “It's absolutely incredible to think about."

"However, Curnoe is not sure the find constitutes a new species. At least, not yet.
“Whilst I'm convinced that the material they've found is very unusual, I'm not convinced at the moment that there's enough evidence to warrant a new species,” he says.

"The team is now working on dating some of the animal bones found in the same layer as the hominin remains, to get a better idea of when these archaic people lived. "

Comment: All i can say ism herec we go again.

http://blogs.discovermagazine.com/crux/2019/01/28/human-skin-color-explained-vitamind-f...

"Human skin color reflects an evolutionary balancing act tens of thousands of years in the making. There’s a convincing explanation for why human skin tone varies as a global gradient, with the darkest populations around the equator and the lightest ones near the poles. Put simply, dark complexion is advantageous in sunnier places, whereas fair skin fairs better in regions with less sun.

"That may seem obvious, considering the suffering that ensues when pale folks visit the beach. But actually, humanity’s color gradient probably has little to do with sunburn, or even skin cancer. Instead, complexion has been shaped by conflicting demands from two essential vitamins: folate and vitamin D. Folate is destroyed by the sun’s ultraviolent (UV) radiation. Whereas the skin kickstarts production of vitamin D after being exposed to those same rays.

"Hence, the balancing act: People must protect folate and produce vitamin D. So humans need a happy medium dosage of sun that satisfies both. While the intensity of UV rays is dictated by geography, the amount actually penetrating your skin depends on your degree of pigmentation, or skin color.

***

"Several million years ago, our ancestors’ skin tone would not have been obvious. That’s because early hominins were almost certainly cloaked in dark fur. But beneath the body hair, they probably had pale skin based on the fact that our evolutionary cousins, chimpanzees and gorillas, have light skin under dark fur today.

"Our ancestors eventually lost this fur and gained pigment in their skin. Although the exact timing and causes are debated, many researchers agree that when humans lost their fur, it helped us stay cool while foraging as upright-walking bipeds in the sunny, open habitats of equatorial Africa. The tradeoff, however, was bare skin that was exposed to intense, year-round UV rays. In this context — roughly 1 to 2 million years ago — darker skin was likely better to protect folate stores.

"Why is folate so important? The nutrient plays a role in DNA activities, but its major impact is on evolutionary fitness — one’s ability to survive and reproduce — through fetal development.

***

"Experiments have shown that sunlight breaks down folate, as an isolated molecule, in blood plasma and in skin biopsies. It’s thought that dark skin impedes this because it contains higher amounts of melanin, a dark-brown pigment that absorbs UV rays and chemically disarms their harmful by-products.

***

"But the human lineage did not remain exclusively in equatorial Africa. At different times, people ventured both north and south, to higher latitudes with less sunlight.

That’s when vitamin D became a problem. Like folate, this vitamin is important for evolutionary fitness. It facilitates absorption of calcium, necessary for healthy bones and immunity. Vitamin D can be made in the skin, but only when the process is initiated by certain wavelengths of UV rays.

***

"In studies comparing dark and light-skinned residents of northern cities, paler people had higher vitamin D levels throughout the year. Their less pigmented skin let in more rays.

***

"A range of skin colors evolved at different times, in different populations, as human spread across the globe. In addition to these genetic biological changes, groups have also developed cultural adaptations to deal with variable sunlight. For instance, we can consume diets rich in folate and vitamin D. We can also build shelters, wear clothing and slather sunscreen to block UV rays."

Comment: These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation.

https://medicalxpress.com/news/2019-01-intestinal-immune-cells-key-role.html

"The team's study focused on a protein called integrin β7, which is known to direct immune cells to the gut but not previously to have any influence over metabolism. The MGH team initially found that mice lacking the gene for integrin β7 and fed a normal diet gained equal amounts of weight as did a group of control animals, even though the β7-negative animals ate more food and were equally as active. Metabolic testing indicated that the β7-negative mice converted more food into energy, suggesting they had a higher basal metabolism. They also burned more glucose in brown fat, were more glucose tolerant, had lower triglyceride levels and better fat tolerance than did control mice.

"To investigate whether these benefits persisted under nutritional conditions known to induce the metabolic syndrome—a group of symptoms associated with type 2 diabetes and cardiovascular disease—they fed both β7-negative mice and control mice a diet high in fat, sugar and sodium. The β7-negative mice remained lean, glucose tolerant, and did not develop hypertension or other typical results of a high-fat diet. The control mice did become obese, with elevated blood pressure and reduced glucose tolerance.

***

"Experiments with a mouse model genetically programmed to develop elevated cholesterol found that blocking β7 expression in the bone marrow, where immune cells are generated, maintained normal lipid levels in the animals, in spite of their being fed a high-cholesterol diet. Mice with β7-negative marrow excreted more cholesterol, had improved glucose tolerance and were less likely to develop arterial plaques and other cardiovascular risk factors than were animals with normal bone marrow expression of β7.

"A search for the cells responsible for β7's metabolic impact revealed that the protein's expression was highest in a group of T cells present in the lining of the small intestine. While β7 guides several types of immune cells to the intestines, only these β7-expressing intraepithelial T cells appear to regulate systemic metabolism. Swirski's team showed they do so by reducing levels of a protein called GLP-1, which normally increases metabolism by stimulating insulin secretion and glucose uptake.

"Swirski explained that the metabolism-suppressing role of β7-positive intraepithelial T cells might have developed to prevent starvation under conditions of nutrient scarcity. "At times when the availability of food is uncertain, it would be advantageous to have a system that converts some of the energy ingested with food into fat. But during times of over-nutrition, such a system can backfire and lead to the cardiovascular disease that is so prevalent today," he says."

Comment: This is just the first insight into how the body controls its metabolic rate.

https://phys.org/news/2019-01-reveal-deep-history-archaic-humans.html

"Situated in the foothills of Siberia's Altai Mountains, it is the only site in the world known to have been occupied by both archaic human groups (hominins) at various times.

***

"The new studies show that the cave was occupied by Denisovans from at least 200,000 years ago, with stone tools in the deepest deposits suggesting human occupation may have begun as early as 300,000 years ago. Neanderthals visited the site between 200,000 and 100,000 years ago, with "Denny", the girl of mixed ancestry, revealing that the two groups of hominins met and interbred around 100,000 years ago.

"Most of the evidence for Neanderthals at Denisova Cave falls within the last interglacial period around 120,000 years ago, when the climate was relatively warm, whereas Denisovans survived through much colder periods, too, before disappearing around 50,000 years ago.

"Modern humans were present in other parts of Asia by this time, but the nature of any encounters between them and Denisovans remains open to speculation in the absence of any fossil or genetic traces of modern humans at the site.

"The Oxford team also identified the earliest evidence thus far in northern Eurasia for the appearance of bone points and pendants made of animal teeth that are usually associated with modern humans and signal the start of the Upper Palaeolithic. These date to between 43,000 and 49,000 years ago.

"So, 'while these new studies have lifted the veil on some of the mysteries of Denisova Cave, other intriguing questions remain to be answered by further research and future discoveries' said Professor Richard 'Bert' Roberts, a co-author on the two papers.

"Professor Higham commented that 'it is an open question as to whether Denisovans or modern humans made these personal ornaments found in the cave. We hoping that in due course the application of sediment DNA analysis might enable us to identify the makers of these items, which are often associated with symbolic and more complex behaviour in the archaeological record'."

Comment: All of this new Homo species is because genetic analysis tells us they are a separate group. Were they a very small group? Time and discoveries will tell.

https://www.quantamagazine.org/genetics-spills-secrets-from-neanderthals-lost-history-2...

"Approximately 750,000 years ago, according to Rogers, the forerunners of Neanderthals and Denisovans left the ancestors of modern humans behind in Africa to make their way across Eurasia’s expansive territory. Once on their own, something nearly wiped them out entirely; the genetic data shows the population passed through a severe bottleneck, never observed in previous studies. But whatever caused that brush with disaster, the archaic humans bounced back from it, and just a few thousand years later — by 744,000 years ago — they separated into two separate lineages, the Neanderthals and the Denisovans. The former then split further into the smaller regional groups that so fascinated Rogers.

"The dating of that schism between the Neanderthals and the Denisovans is surprising because previous research had pegged it as much more recent: a 2016 study, for instance, set it at only 450,000 years ago. An earlier separation means we should expect to find many more fossils of both eventually. It also changes the interpretation of some fossils that have been found. Take the large-brained hominid bones belonging to a species called Homo heidelbergensis, which lived in Europe and Asia around 600,000 years ago.

"Paleoanthropologists have disagreed about how they relate to other human groups, some positing they were ancestors of both modern humans and Neanderthals, others that they were a nonancestral species replaced by the Neanderthals, who spread across Europe.
Rogers’ findings imply that the H. heidelbergensis had to have been an early Neanderthal. “The separation time we estimate is so early that a European hominid from 600,000 years ago pretty much has to be a Neanderthal,” he said, “at least genetically, even if they didn’t look entirely like Neanderthals yet.”

"Coincidentally or otherwise, this new reconstruction of the Neanderthals’ complicated early history closely resembles what we learned about the populations of anatomically modern people who first spread into Europe and Asia. Nearly 50,000 years ago, Eurasians separated from Africans, experienced a bottleneck period during which their population was very low, and then splintered into regional populations throughout Eurasia — the so-called out-of-Africa theory of human migration. “It looks like the same thing happened 600,000 or 700,000 years ago” with the Neanderthals and Denisovans, Rogers said. “There was another out-of-Africa diaspora that no one had previously suspected.”

"It’s no secret that the Neanderthals struggled: The glacial periods they endured and the fragmentation of their population left them unable to support robust social or technological growth. “But the one misconception people have is that we represent progress, that modern humans are the best and Neanderthals beneath us,” Hawks said. “When it comes to being hunters, being reliant on high-energy food resources in marginal environments, Neanderthals were the extreme.” He added, “They solved problems we don’t face today. How did they live at such low population densities for hundreds of thousands of years? That’s something we never managed.”

Comment: The point that Neanderthals had to deal with glaciation and survived them indicates they were quite capable folks. It is obvious we are still learning about our antecedents.