Hello Nature readers,
Today we track the effects of oral contraceptives on the brain, learn that AI can help people with opposing views come to a consensus and celebrate a hero of scientific research: C. elegans.

Self-scans reveal pill-induced brain changes

Neuroscientist Carina Heller scanned her own brain 75 times over a year to study the effects of the menstrual cycle and oral contraceptives on the brain. She found a rhythmic pattern of change in brain volume and connectivity between brain regions over the course of her natural cycle, with volume and connectivity dipping slightly while she was taking the pill. Heller has joined a group of investigators filling gaps in women's health research by scanning their own brains. “She gave herself up to science,” says neuroscientist Emily Jacobs. “And as a result, we now have this greater insight into the human brain.”

If you build it, they will (hopefully) come

Researchers in central Mexico have transplanted a forest of almost 1,000 oyamel fir trees (Abies religiosa) to a mountain in Michoacán. If they survive a few decades, the trees could help to shield the migratory eastern population of monarch butterflies (Danaus plexippus), which spend the winter roosting in oyamel fir forests, from the impacts of climate change. It would require a lot of effort to plant enough trees to provide refuge for the butterflies, “but that may be the only choice down the road,” says ecologist John Pleasants.

AI helps opponents find common ground

A chatbot-like tool powered by artificial intelligence (AI), developed by Google DeepMind, can help people with differing views to find areas of agreement. In an experiment with online discussion groups, the model was able to synthesize diverging opinions and produce summaries of each group’s position that took different perspectives into account. Participants preferred the AI-generated statements to ones written by human mediators. However, the model was not trained to intervene in the debate, which means that if applied in the real world, the model’s statements could include extremist or other problematic beliefs expressed by participants.

Magma station to test new energy source

Studying how magma behaves underground could help harness powerful geothermal energy. Scientists from the Krafla Magma Testbed (KMT) in Iceland plan to drill into the magma beneath the Krafla volcano, starting in 2027. Pressure and temperature sensors will be placed in the first of two boreholes to track changes to the magma, which could help predict volcanic eruptions. The second will house a test run for a new type of geothermal power station. “[Magma] are the heat source that power the hydrothermal systems that lead to geothermal energy. Why not go to the source?” says Yan Lavallée, volcanologist and head of KMT’s science committee.

The “badass” worm behind 4 Nobel Prizes

“If we understand the worm, we understand life,” says geneticist Robert Waterson. He isn’t talking about just any worm, he’s referring to Caenorhabditis elegans, the 1 millimetre nematode that’s been extensively studied as a model organism. Research using this species has resulted in at least 4 Nobel Prizes, with a recipient making sure to shout-out their favourite worm each time. One of the winners of this year’s Nobel Prize in Physiology or Medicine, molecular biologist Gary Ruvkun, lauded the species with its highest honour so far, recognizing it as “badass”.

What if you can’t write a strong reference?

You’ve received yet another request to write a recommendation letter, but you’re not sure you can give this particular candidate a glowing reference. What now? If politely declining isn’t an option, it’s important to view the candidate in the most positive light while also noting their limitations in a constructive way. “You may not have the best experience working with them, but in a different environment, they might end up being a superstar,” says biochemist James Murphy.

Don’t rush rules for sharing genetic data

Today, the 16th meeting of the Conference of the Parties to the Convention on Biological Diversity (COP16) begins in Cali, Colombia. High on the agenda is reaching an agreement on how lower-income countries can better share in the benefits that stem from their resources — including any monetary benefits deriving from genetic sequence data. But as late as last week, draft text on the matter contained 200 unfinalized points. Delegates must not rush an agreement, says a Nature editorial, or they risk disrupting research without notably benefiting lower-income countries.