Daily briefing: How koalas escaped a genetic bottleneck

## Summary
Nature | 4 min read Reference: Science paper Protein-clearing cells break in Alzheimer’s Tanycytes — specialized cells that clear toxic proteins from the brain — malfunction in people with Alzheimer’s disease , which leads to the build-up of abnormal tau proteins that characterizes the condition. Nature | 4 min read Reference: Cell Press Blue paper A Möbius molecule with a new twist Chemists have synthesized a new type of carbon-based molecule with an unprecedented twist in its structure. Nature | 4 min read Reference: Science paper International Women’s Day 2026 How and why to filter men out of the data Across many conditions, women’s health is uncharted scientific territory. We never know how we might apply them.” By comparing samples of moss recovered from a crime scene in a cemetery with those kept in the collection of the Field Museum in Chicago, plant scientist Matt von Konrat found evidence that helped to solve a case involving more than 100 grave robberies. ( The Guardian | 4 min read ) Reference: Forensic Sciences Research paper doi: https://doi.org/10.1038/d41586-026-00771-x In today’s penguin-search puzzle, Leif Penguinson is exploring the exposed bed of the Mayo-Louti river in Cameroon during a dry spell.

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In some parts of Australia, koalas were hunted nearly to extinction by the early twentieth century.
Credit: VCG via Getty
How these koalas came back from the brink
Koalas (
Phascolarctos cinereus
) in Victoria, Australia recovered from a severe genetic bottleneck through an increase in recombination — a process in which the DNA from two parents gets shuffled to form new sequences in their offspring — during a rapid population expansion. Researchers found that the number of individuals that breed and contribute to the next generation’s gene pool has
jumped substantially in the past few decades, despite previously collapsing by more than 90%
. The findings suggest that even species pushed to the brink of extinction can recover lost genetic diversity.
Nature | 4 min read
Reference:
Science
paper
Protein-clearing cells break in Alzheimer’s
Tanycytes — specialized cells that clear toxic proteins from the brain —
malfunction in people with Alzheimer’s disease
, which leads to the build-up of abnormal tau proteins that characterizes the condition. From samples of blood and cerebrospinal fluid (CSF), researchers found that less tau had moved from the CSF to the bloodstream in people with Alzheimer’s compared with people who did not have the disease, which suggested that tanycytes weren’t working properly. They then looked at post-mortem tissue samples and found that tanycytes were destroyed or fragmented in people with Alzheimer’s.
Nature | 4 min read
Reference:
Cell Press Blue
paper
A Möbius molecule with a new twist
Chemists have synthesized a new type of carbon-based molecule with an unprecedented twist in its structure. The team
calls the looped molecule a ‘half-Möbius’
, inspired by the Möbius strip — a twisted loop with one continuous surface. In the half-Möbius molecule, the chain of atoms is twisted by 90° to make the loop, instead of the full 180º seen in a standard Möbius strip. The molecule can exist in two versions depending on whether it twists left or right. The versions differ in chirality, meaning that they are mirror images of each other.
Nature | 4 min read
Reference:
Science
paper
International Women’s Day 2026
How and why to filter men out of the data
Across many conditions, women’s health is uncharted scientific territory. Until the 1990s, women were rarely included in clinical studies and female animals were excluded from studies using model organisms because of a prevailing belief — now discredited — that hormonal fluctuations made their biology too complicated.
Disaggregating data by sex is a powerful way to help fill in the blanks
— but researchers say it’s not used enough.
Nature | 16 min read
The missing pieces of menopause science
“We’re not good at treating perimenopause because we don’t completely understand it,” says endocrinologist Susan Davis, who has studied menopause for decades.
The hormonally turbulent years leading up to a woman’s final period have been neglected by science
compared with postmenopausal studies, which focus on life after a year without menstrual bleeding. That’s left a knowledge gap that frustrates providers and their patients. “I can tell you these treatments are helping my patients relieve their symptoms,” says gynaecologist Rachel Pope. “But I can’t tell you from our current data what that means several decades from now.”
Nature | 17 min read
The women who inspire inspiring women
Six winners of three
Nature
-sponsored awards — the Estée Lauder Companies’ Inspiring Women in Science award, the Sony Women in Technology award and the John Maddox Prize — name
women whom they find inspiring themselves.
The nominated individuals include Anna Abalkina, a research-integrity scholar who had to relocate from Russia to Germany, and Onikepe Owolabi, who published a landmark study of post-abortion care in ten countries.
Nature | 13 min read
Read more in
Nature
’s collection for International Women’s Day
.
Features & opinion
Using maths to crack Mexico’s drug cartels
Mathematician Rafael Prieto-Curiel and his colleagues have created
a mathematical model that revealed Mexico’s powerful drug cartels are the country’s fifth-largest employer
. The model suggests that the government’s current strategy could lead to more casualties, more incarceration — and bigger cartels. “That result is one of the darkest results I have ever had in my research career,” says Prieto-Curiel. But finding ways of preventing people from joining organized crime groups could cut casualties and reduce cartel size — if they can be successfully implemented in the real world.
Nature | 14 min read
Futures:
All the world is staged
A dedicated scientist must follow the call of the wild in
the latest short story for
Nature
’s Futures
series.
Nature | 6 min read
Five best sci

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## Expert Analysis

### Merits
- The nominated individuals include Anna Abalkina, a research-integrity scholar who had to relocate from Russia to Germany, and Onikepe Owolabi, who published a landmark study of post-abortion care in ten countries.
- Nature | 4 min read Quote of the day “It underscores how important natural history collections are.

### Areas for Consideration
- That’s left a knowledge gap that frustrates providers and their patients. “I can tell you these treatments are helping my patients relieve their symptoms,” says gynaecologist Rachel Pope. “But I can’t tell you from our current data what that means several decades from now.” Nature | 17 min read The women who inspire inspiring women Six winners of three Nature -sponsored awards — the Estée Lauder Companies’ Inspiring Women in Science award, the Sony Women in Technology award and the John Maddox Prize — name women whom they find inspiring themselves.

### Implications
- The model suggests that the government’s current strategy could lead to more casualties, more incarceration — and bigger cartels. “That result is one of the darkest results I have ever had in my research career,” says Prieto-Curiel.
- But finding ways of preventing people from joining organized crime groups could cut casualties and reduce cartel size — if they can be successfully implemented in the real world.
- We never know how we might apply them.” By comparing samples of moss recovered from a crime scene in a cemetery with those kept in the collection of the Field Museum in Chicago, plant scientist Matt von Konrat found evidence that helped to solve a case involving more than 100 grave robberies. ( The Guardian | 4 min read ) Reference: Forensic Sciences Research paper doi: https://doi.org/10.1038/d41586-026-00771-x In today’s penguin-search puzzle, Leif Penguinson is exploring the exposed bed of the Mayo-Louti river in Cameroon during a dry spell.
- The answer will be in Monday’s e-mail, all thanks to Briefing photo editor and penguin wrangler Tom Houghton.

### Expert Commentary
This article covers nature, briefing, read topics. Notable strengths include discussion of nature. Areas of concern are also raised. Readability: Flesch-Kincaid grade 0.0. Word count: 1335.