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Artist’s illustration of DNA molecules.

Christoph Burgstedt/Science Photo Library

‘Complete’ 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 The work is described in a preprint, and has not yet been peer reviewed.

STAT | 6 min read

Reference: bioRxiv preprint

Scottish tomb home to prehistoric carvings

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. “This was a completely amazing and unexpected find and, to me, discoveries like this are the real treasure of archaeology, helping to reshape our understanding of the past,” Fenton says.

The Guardian | 4 min read

Mapping the Universe’s dark matter

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.

Nature | 5 min read

DARK MATTER MAP: oval shaped map of the sky with dark matter shown as a purple region

Credit: N. Jeffrey/Dark Energy Survey collaboration

Slime moulds remember their meals

The slime mould Physarum polycephalum has no brain or nervous system — yet it somehow ‘remembers’ the location of food that it ate. Slime molds 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.

Scientific American | 3 min read

Reference: PNAS paper

37%

The estimated proportion of heat-related deaths over the past three decades that were caused by climate change, according to a study of global temperature and mortality. (New Scientist | 3 min read)

Reference: Nature Climate Change paper

Features & opinion

Tackling India’s COVID crisis

Strategies for tackling COVID-19 must include better, faster ways to spot and stop the spread of more-transmissible coronavirus variants, says physician-scientist Anurag Agrawal, who co-leads India’s SARS-CoV-2 molecular-surveillance efforts. This will require more sharing of data and methods; funding to develop better predictions and simpler tests; and integration of genomics, informatics and public health.

Nature | 5 min read

The highs and lows of old-school computing

Antiquated computers are common in science. Often, an old computer is hooked up to an expensive piece of scientific kit with software that is incompatible with newer computers or too expensive to upgrade. Sometimes, the old computer just refuses to die, or is so in demand that it’s impractical to decommission it for long enough to upgrade it. Whatever the reason, for many scientists, keeping their old computers ticking over is of paramount concern — and a labour of love.

Nature | 8 min read

Celebrating 100 days on Mars

Since touching down on 18 February, NASA’s Perseverance rover has spent 100 Martian days on the red planet, where it has captured some stunning photographs of Jezero Crater. Check out a selection of snaps from the mission so far, including aerial pictures taken by the tiny helicopter Ingenuity.

BBC News | 3 min read

Futures: What big teeth you have

A Tyrannosaurus rex robot assassin struggles to stay on target in the latest short story for Nature’s Futures series.

Nature | 5 min read

Quote of the day

“Not only should we not always trust the machine, we can’t always trust the person that interprets the machine.”

A study has shown that digital-forensics experts can be unintentionally biased when examining evidence from computer hard drives. (The Guardian | 5 min read)