Human Evolution

[Jo Bowyer]

A new hominid species has been found in a Philippine cave, fossils suggest

https://www.sciencenews.org/article/...test_Headlines

[Jo Bowyer]

A Neanderthal tooth discovered in Serbia reveals human migration history

https://theconversation.com/a-neande...tion%20history

The Neanderthals were a group of ancient humans who lived in western Eurasia during the Pleistocene epoch. Their earliest ancestors lived in Spain almost half a million years ago, and their range gradually expanded eastward through Europe and the Levant and as far as Siberia.

But around 100,000 years ago, modern humans (like us) started to migrate out of Africa and into Eurasia. By 40,000 years ago, Neanderthals began to disappear from Europe, retreating westward as modern humans moved in on their territory. And, around 30,000 years ago, the last remaining Neanderthals in Spain died out.

The timing of the Neanderthal demise and the modern human conquest of Europe can’t be a coincidence. Ten years ago, most paleoanthropologists would have told you that our two groups were competitors: Neanderthals were bigger and stronger, but we were smarter, and in the battle for survival in the harsh landscape, brains beat out brawn.

Attitudes quickly changed in 2010 when the Neanderthal genome was sequenced for the first time, and along with it we discovered that all living humans outside of sub-Saharan Africa carry a small amount of Neanderthal DNA. More recently, we’ve discovered that they carried some of our genes too.

[Jo Bowyer]

Cereal processing at Early Neolithic Göbekli Tepe, southeastern Turkey

https://journals.plos.org/plosone/ar...l.pone.0215214

The organization of work and food supply has always been a central question of research into Göbekli Tepe, as the construction and maintenance of the monumental architecture would have necessitated a considerable work force. Contextual analyses of the distribution of the elements of the grinding kit on site highlight a clear link between plant food preparation and the rectangular buildings and indicate clear delimitations of working areas for food production on the terraces the structures lie on, surrounding the circular buildings. There is evidence for extensive plant food processing and archaeozoological data hint at large-scale hunting of gazelle between midsummer and autumn. As no large storage facilities have been identified, we argue for a production of food for immediate use and interpret these seasonal peaks in activity at the site as evidence for the organization of large work feasts.

[Jo Bowyer]

A jawbone shows Denisovans lived on the Tibetan Plateau long before humans

https://www.sciencenews.org/article/...orspicks050519

The fossil suggests that these perplexing, extinct members of the human lineage weathered the plateau’s frigid, thin air long before humans did.

[Jo Bowyer]

It’s time we stopped human evolution – geneticist

https://theconversation.com/its-time...0%20geneticist

As society has become ever more convenient, hygienic and wrapped in cling film, many hark back with dewy eyes to the natural and supposedly wholesome lifestyles of our ancestors in pre-industrial times. Besides the fear around vaccines, growing numbers of people put their faith in the organic movement, the anti-GM lobby and New Age philosophies. They have increasingly rejected the ability of science to improve our lives, placing an almost religious trust in the benevolence of Mother Natureinstead.

Coupled with this is a very positive view of evolution. It is seen as a caring and compassionate force which has shaped us and the rest of the natural world. It almost seems that there is the growing belief that if natural evolution were left to its own devices, then everything would work out for the best.

[Jo Bowyer]

The African ape-like foot of Ardipithecus ramidus and its implications for the origin of bipedalism

https://elifesciences.org/articles/4...19-elife-alert

Walking on two legs is considered to be one of the first steps towards becoming human. While some animals are also able to walk on two legs, such as kangaroos, birds, and some rodents, the way they move is nevertheless quite distinct to the way humans walk.

How animals evolve traits is influenced by the characteristics of their ancestors. But what exactly was the common ancestor of humans and chimpanzees like? Most primates are suited for a life in the trees. But some also have skeletal characteristics associated with living on the ground. For example, the feet of chimpanzees and gorillas show adaptations that suit life on the ground, such as walking on the sole of the foot with a heel first foot posture. So far, it was unclear whether the ancestor of humans and chimpanzees was primarily adapted to living on the ground or in the trees.

To investigate this further, Prang studied the oldest-known fossil foot (4.4 million years) attributed to the hominin Ardipithecus ramidus.

[Jo Bowyer]

An ancient pouch reveals the hallucinogen stash of an Andes shaman

https://www.sciencenews.org/article/...test_Headlines

A leather bag stuffed with ritual items, found high in the Andes Mountains, has yielded rare clues to South American shamans’ hallucinatory visions around 1,000 years ago.

[Jo Bowyer]

Fossil teeth push the human-Neandertal split back to about 1 million years ago

https://www.sciencenews.org/article/...test_Headlines

People and Neandertals separated from a common ancestor more than 800,000 years ago — much earlier than many researchers had thought.

Many researchers have presumed that a species dubbed Homo heidelbergensis, thought to have inhabited Africa and Europe, originated around 700,000 years ago and gave rise to an ancestor of both Neandertals and Homo sapiens by roughly 400,000 years ago. Genetic evidence that Sima de los Huesos fossils came from Neandertals raised suspicions that a common ancestor with H. sapiens existed well before that (SN Online: 3/14/16). Recent Neandertal DNA studies place that common ancestor at between 550,000 and 765,000 years old. But those results rest on contested estimates of how fast and how consistently genetic changes accumulated over time.

With that molecular debate in mind, Gómez-Robles calculated the rate at which eight ancient hominid species evolved changes in tooth shape. That enabled her to gauge how long it must have taken for Sima de los Huesos teeth to evolve after Neandertals diverged from a common ancestor with H. sapiens.

Gómez-Robles used two possible evolutionary trees for the eight hominid species to estimate dental evolution rates. Aside from the Spanish Neandertals and Stone Age H. sapiens, teeth in her study came from African hominids dating to as early as 3.2 million years ago.

[Jo Bowyer]

Factors associated with chronic and acute back pain in Wales, a cross-sectional study

https://bmcmusculoskeletdisord.biome...891-019-2477-4

[Jo Bowyer]

DNA from 10,000 year old chewing gum reveals the secrets of Stone Age Scandinavians

https://theconversation.com/dna-from...0Scandinavians

[Jo Bowyer]

Cave debris may be the oldest known example of people eating starch

https://www.sciencenews.org/article/...orspicks060219

Small fire pits in a South African cave have yielded what researchers regard as the oldest known examples of a key dish in ancient humans’ daily menu.

Based on plants that would have been locally available, Stone Age people likely cooked tubers and roots in the cave, the scientists say. Compared with raw starchy plants, their cooked counterparts would have provided an especially efficient source of glucose, and thus energy, to people. Human fossils previously found in the coastal cave, located at Africa’s southern tip, also date to around 120,000 years ago.

Ancient starch eating at Klasies River Cave supports the possibility that Homo sapiens evolved genetic upgrades to help with digesting hard-to-break-down starch long before people started farming starchy crops in Africa around 10,000 years ago. Scientists have determined that people today carry more copies of starch-digestion genes than did Stone Age populations, such as Neandertals and Denisovans.

Ancient humans in southern Africa likely ate a mix of cooked roots and tubers, shellfish, fish and game animals (SN: 8/13/11, p. 22), Larbey’s team says. Roots and tubers would have been available year-round. And while little is known about the origins of cooking, campfires were being built at least 300,000 years ago in Africa (SN Online: 2/20/14).

[Jo Bowyer]

Nature’s first aid kit: a fungus growing on the side of birch trees

https://theconversation.com/natures-...0birch%20trees

If you’ve ever stopped to admire a birch tree, you may unknowingly have something in common with a 5,300-year-old mummy called Ötzi. In 1991, hikers found Ötzi in an alpine glacier on the Austrian-Italian border, and perfectly preserved with him were pieces of fungus attached to leather cords, safely stowed in his bag. That fungus is the same one you can see growing on birch trees today: the birch polypore.

Numerous studies have revealed that birch polypore does indeed produce compounds with antibiotic, antifungal, anti-inflammatory, antioxidant, and anticancer properties. Piptamine, polyporenic acids and triterpenoids are all compounds produced as part of the fungus’ self-defence mechanism against bacteria, explaining its observed antibiotic value. When tested on dogs and mice suffering from cancer, as well as cancerous cells grown in the lab, birch polypore extracts had a range of anticancer effects such as reducing tumour size and cell growth.

It’s hard to identify the mechanisms producing these results, however, as the activity of specific birch polypore compounds is not well understood – they have mostly been studied together in one combined extract, rather than individually isolated. Even more intriguing is that this whole cocktail seems to be more effective than single compounds, which may be a result of a synergistic interaction between the separate ingredients. Further research will be needed to disentangle the relationships in the birch polypore cocktail.

[Jo Bowyer]

A multidisciplinary approach to a unique palaeolithic human ichnological record from Italy (Bàsura Cave)

https://elifesciences.org/articles/4...19-elife-alert

Based on the integration of laser scans, sedimentology, geochemistry, archeobotany, geometric morphometrics and photogrammetry, here we present evidence testifying that a Palaeolithic group of people explored a deep cave in northern Italy about 14 ky cal. BP. Ichnological data enable us to shed light on individual and group level behavior, social relationship, and mode of exploration of the uneven terrain. Five individuals, two adults, an adolescent and two children, entered the cave barefoot and illuminated the way with a bunch of wooden sticks. Traces of crawling locomotion are documented for the first time in the global human ichnological record. Anatomical details recognizable in the crawling traces show that no clothing was present between limbs and the trampled sediments. Our study demonstrates that very young children (the youngest about 3 years old) were active members of the Upper Palaeolithic populations, even in apparently dangerous and social activities.

[Jo Bowyer]

Why humans (or something very similar) may have been destined to walk the Earth

https://theconversation.com/why-huma...%20the%20Earth

But what about the underlying physical laws – do they favour predictable evolution? At very large scales, it appears so. We know of many governing laws of our universe that are certain. Gravity, for example – for which we owe our oceans, thick atmosphere and the nuclear fusion in the sun that showers us with energy – is a predictable force. Isaac Newton’s theories, based on large scale deterministic forces, can also be used to describe many systems on large scales. These describe the universe as perfectly predictable.

If Newton’s view was to remain perfectly true, the evolution of humans was inevitable. However, this comforting predictability was shattered by the discovery of the contradictory but fantastical world of quantum mechanics in the 20th century. At the smallest scales of atoms and particles, true randomness is at play – meaning our world is unpredictable at the most fundamental level.

This means that the broad “rules” for evolution would remain the same no matter how many times we replayed the tape. There would always be an evolutionary advantage for organisms that harvest solar power. There would always be opportunity for those that make use of the abundant gases in the atmosphere. And from these adaptations, we may predictably see the emergence of familiar ecosystems. But ultimately, randomness, which is built into many evolutionary processes, will remove our ability to “see into the future” with complete certainty.

[Jo Bowyer]

Extra fingers, often seen as useless, can offer major dexterity advantages

https://www.sciencenews.org/article/...test_Headlines

An extra finger can be incredibly handy. Two people born with six fingers per hand can tie their shoes, adroitly manage phones and play a complicated video game — all with a single hand, a study shows.

These people’s superior dexterity, described June 3 in Nature Communications, suggests that instead of being seen as aberrations that ought to be surgically removed, extra fingers can bring benefits. The results also highlight how flexible the human brain can be, a feature that will be central to the design of brain-controlled robotic appendages.