Mysterious skull fossils expand human family tree

Fossils found in Israel hint that a previously unknown group of hominins — the Nesher Ramla people — were the direct ancestors of Neanderthals. And researchers have suggested that an ancient human skull found in China in the 1930s could belong to a new species, Homo longi (Dragon Man), which might be an even closer relative of modern humans than are Neanderthals. But both findings have sparked debate among scientists. The studies are based on analyses of the size, shape and structure of fossilised bones — methods that are subject to individual judgement and interpretation. As is often the case for fossil finds, there is no DNA evidence.

Ancient Siberian cave hosted Neanderthals, Denisovans, and modern humans—possibly at the same time

In the past decade, a mere eight human fossils unearthed in the Denisova Cave in southern Siberia have rewritten the human story, from the tiny finger bone that revealed the extinct human Denisovans, to the discovery of a first-generation Neanderthal–Denisovan hybrid. Now a study of DNA in the cave’s soil reveals the complex history of human and animal habitation there. Hundreds of soil samples show a cycle of inhabitants, starting with Denisovans about 300,000 years ago. Different groups of Denisovans and Neanderthals left their marks on the cave, and modern humans appeared about 45,000 years ago.

Neolithic Diets Before The Domestication Of Crops

The people who built the ancient monumental structures at Turkey’s Göbekli Tepe were fuelled by vat-fulls of starchy porridge and stew, not just meaty feasts. Archæologists are uncovering evidence that ancient people were grinding grains for hearty, starchy dishes long before we domesticated crops. These discoveries shred the long-standing idea that early people subsisted mainly on meat.

Giant rhino unearthed in China

A new species of ancient giant rhino, Paraceratherium linxiaense, weighed about 21 tonnes and could reach up to 7 metres high. But they wouldn't have had the rhino’s namesake horn — which evolved later — and would have looked more like a really, really big horse.

Quantum microscope can examine cells in unprecedented detail

A microscope that harnesses quantum entanglement can image biological structures with unprecedented sharpness. The technique ‘squeezes’ light to produce correlations between photons in one of the lasers used by an optical imaging method called stimulated Raman scattering gain microscopy. The squeezed light suppresses noise in the microscope’s signal, improving the sensitivity.

Mysterious fast radio bursts come in two distinct flavours

A bumper crop of fast radio bursts (FRBs) shows that the mysterious signals come in two distinct types. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio telescope has detected 535 FRBs — quadrupling the known tally of these powerful cosmic flashes, which flare for just milliseconds. Most of them are one-offs, but a minority repeat periodically and last at least ten times longer than average. The findings suggest that FRBs might originate from at least two astrophysical phenomena — bringing us a step closer to solving one of astronomy’s biggest puzzles.

Microfossils reveal mysterious shark die-off

Up to 90% of the global shark population was wiped out in a mass extinction around 19 million years ago. Researchers identified the disappearance by studying microfossils in deep-sea sediment cores collected in the North and South Pacific oceans. After thriving for some 40 million years, shark numbers and diversity suddenly dropped and have not recovered since.

Radioactivity May Fuel Life Deep Underground and Inside Other Worlds

Scientists have long puzzled over how microbes living deep underground feed themselves without sunlight or heat. Now, two studies suggest that these organisms could feed off the radioactive decay of hydrogen and other elements. The findings open up new possibilities for life on other worlds — and could shed some light on our planet’s own history.

How Slime Moulds Remember Where They Ate

The slime mould Physarum polycephalum has no brain or nervous system — yet it somehow ‘remembers’ the location of food that it ate. Slime moulds are simple organisms made up of interlacing tubes — but previous research has shown they can solve complex problems, such as finding the shortest path through a maze. Scientists found that when parts of P. polycephalum come into contact with a food source, they release a substance that softens the gel-like walls of its tubes, making them widen. The slime mould moves by expanding along wider tubes and pruning narrower ones, so the enlarged tubes effectively record past food sites.

Prehistoric carvings of red deer found in Scottish neolithic tomb

Rock carvings depicting red deer have been found in a Bronze Age burial mound in Scotland. Archaeology graduate Hamish Fenton discovered the carvings by chance while visiting Kilmartin Glen in Argyll, an area known for Neolithic and Bronze Age sites. They are between 4,000 and 5,000 years old, the oldest known carvings of this type in the United Kingdom.

The most detailed 3D map of the Universe ever made

A survey of the southern sky has reconstructed how mass is spread across space and time in the biggest study of its kind. Cosmologists observed the sky between 2013 and 2019 using a 570-megapixel camera at the Víctor M. Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile. The resulting 3D cosmic map provides a record of the Universe’s history. By tracking how galaxies spread out over time, researchers can measure the forces at play. These include the gravitational pull of dark matter — the invisible stuff that constitutes some 80% of the Universe’s mass — and dark energy, the mysterious force that appears to be pushing the Universe to accelerate its expansion.

‘Entire’ human genome sequence unveiled

An international team of scientists claims to have sequenced the entirety of the human genome, including parts that were missed in the first sequencing of the human genome 20 years ago. That historic draft, and subsequent sequences, have all missed about 8% of the genome. The most recent effort fills in these gaps using new sequencing technologies. It has different limitations, however, including the type of cell line used. The work is described in a preprint, and has not yet been peer reviewed.