Hello Nature readers,
Today we discover that Earth’s solid iron-nickel core has two distinct layers, meet the UK government’s new chief scientific adviser and consider whether AI writing tools could give scientists the ‘gift of time’.

Quakes reveal secrets of Earth’s inner core

Measurements of earthquake reverberations have revealed that our planet’s inner core — a solid ball of iron nickel — has two distinct layers made mainly of differently structured iron crystals. “Earth oscillates like a bell after a large earthquake,” says geophysicist Hrvoje Tkalčić. The way these oscillations are distorted as they bounce back and forth through the centre of the planets allowed his team to figure out the core’s structure. The finding will help researchers to understand how the core formed millions of years ago and what role it might have had in shaping the magnetic field.

COVID expert is UK chief scientific adviser

Angela McLean, a mathematical biologist who helped to steer the country’s response to COVID-19, has been appointed as the UK government’s next chief scientific adviser. She will take over from clinical pharmacologist Patrick Vallance, who gained a high profile for his unflappable appearances in frequent televised pandemic briefings. McLean will need to “step back from the immediate aftermath of that crisis and look afresh at how well our system is working”, says research-policy analyst James Wilsdon.

Europe’s €10-million boost for early careers

A series of government programmes in the European Union is aimed at re-energizing the career landscape for junior scientists. In Europe, like in many places, early-career researchers are dissatisfied with widespread job insecurity, precarious funding and poor work conditions. But each of the EU’s 27 countries faces unique obstacles, making consensus about solutions difficult to achieve. And clumsy policies can backfire, such as a bid in Berlin to encourage permanent roles that ended up prompting hiring freezes.

New nautiluses: ‘they’re everywhere’

Please welcome three newly described species of the “most mysterious, well-known animal”: the nautilus. Despite being the foundation of an entire shell-trade industry (and countless beautiful fossils), no one has ever seen a nautilus egg in the wild, and we don’t even know how long they live. Researchers developed a non-lethal capture method that allowed them to identify the new species: Nautilus samoaensis (from American Samoa), Nautilus vitiensis (from Fiji) and Nautilus vanuatuensis (from Vanuatu). “They’re everywhere,” says marine biologist and study co-author Gregory Barord. “Each of these seamounts, which there are so many in the Indo-Pacific, appear to have their own unique nautilus species.”

Nigerian elections need science advocates

On Saturday, Nigerians will head to the polls to pick a new president. Science could be part of the solution to the country’s gruelling fuel shortages, perennial electricity outages and deficient technology infrastructure — yet it seemingly has no advocate in the elections, says microbiologist Amina Ahmed El-Imam. Now is the time for the Nigerian Academy of Science to use its influence with the government and for scientists to step out their laboratories to interact with the larger community, she argues. “We must collaborate to pull science in Nigeria out of the cold.”

The sisterhood of species

Cardiologist and evolutionary biologist Barbara Natterson-Horowitz studies the biology of female animals to find potential treatments to improve women’s health. She was first introduced to the multispecies approach in 2005, when she became a cardiovascular consultant to the Los Angeles Zoo. Natterson-Horowitz has since studied ovarian cancer in flamingoes and pythons, menstrual difficulties in great apes and bats, and lactation in cows. “I've learned when it comes to certain aspects of my health, I may have more in common with other female animals than with my husband, brother, son or the other men in my life,” she writes.

Harness the power of AI waffle

Infectious-disease researcher John Tregoning wonders whether artificial-intelligence (AI) writing tools could hand scientists the ‘gift of time’ by doing what chatbots do best: generating generic waffle. “This made me reflect: if there is a section in a grant application that can be written by an AI, does that section really serve any purpose?” asks Tregoning. “But for now, while we are forced to fill in unnecessary boxes on forms, AI offers a way to free up headspace.”