Welcome to Science News Daily, your source for the latest discoveries shaping our understanding of the world. I'm your host, and today we're diving into some fascinating stories that span from ancient yogurt recipes to distant cosmic rings.

Let's start with a culinary discovery that might make you think twice about your breakfast routine. Scientists have successfully recreated a nearly forgotten yogurt-making tradition that once spread across the Balkans and Turkey - and the secret ingredient might surprise you: ants. This isn't just a quirky historical footnote. Researchers publishing in the journal iScience demonstrated that the bacteria, acids, and enzymes found in these insects actually enable fermentation. It's a remarkable example of how traditional knowledge can reveal sophisticated food science that we're only now beginning to understand.

Speaking of surprising discoveries from the past, new research is rewriting what we thought we knew about Ice Age Europe. Scientists have found evidence that hippos - those warm-loving giants we associate exclusively with sub-Saharan Africa today - actually roamed central Europe much longer than previously believed. Fossilized bones from Germany's Upper Rhine region reveal these massive animals survived there far later than scientists once thought, painting a very different picture of Ice Age ecosystems.

Even further back in time, archaeologists in Saudi Arabia have uncovered over 170 ancient rock engravings that may represent some of the earliest monumental artworks in the region. Created between twelve thousand eight hundred and eleven thousand four hundred years ago, these massive figures were carved when water and life returned to the Arabian desert. The discovery suggests these early peoples had sophisticated social and symbolic systems, using art to mark territories and migration routes.

Now let's turn to medical breakthroughs that could impact millions of lives. For the first time, scientists have pinpointed specific brain cells linked to depression. Through genomic mapping of post-mortem brain tissue, researchers identified two types of cells - neurons and microglia - that show altered gene activity in people with depression. This finding reinforces that depression has a clear biological foundation and opens new avenues for treatment development.

In other medical news, a randomized clinical trial suggests that low-dose radiation therapy could offer a safe, non-invasive option for knee osteoarthritis pain relief. This single-treatment approach could provide a conservative alternative to medications and joint surgery for people with mild symptoms.

However, not all medical news is positive. A concerning review from Hebrew University of Jerusalem highlights that finasteride, a widely used hair loss medication, has been associated with depression and suicide for more than twenty years. The researcher is calling for urgent regulatory reform, suggesting that mental health effects have been long dismissed by authorities.

On a more optimistic note, MIT scientists have achieved a major breakthrough in gene editing safety. They've developed a new system that makes sixty times fewer mistakes than previous methods, potentially transforming how we treat hundreds of genetic diseases by fine-tuning the molecular tools that rewrite DNA.

Looking beyond our planet, astronomers have identified the most distant and powerful 'odd radio circle' ever observed - enormous double-ringed radio structures billions of light-years away. These cosmic rings challenge current theories about black hole activity and suggest that galactic winds may play a larger role in shaping the universe than we previously understood.

Closer to home, new evidence suggests Mars may have once hosted a vast northern ocean. Scientists are using clues hidden in Martian rock formations and comparing them to Earth's ancient river systems to piece together the red planet's watery past.

Finally, let's appreciate some of Earth's smallest but most crucial inhabitants. Scientists are celebrating International Coccolithophore Day to honor these microscopic planktonic organisms that are smaller than dust but absolutely vital for Earth's climate. These tiny creatures capture carbon, produce oxygen, and leave behind geological records that help us understand our planet's climate history.

That's all for today's Science News Daily. From ancient ant-based yogurts to cosmic radio rings, science continues to surprise us with discoveries that challenge our assumptions and expand our knowledge. Join us tomorrow for more fascinating stories from the world of science. Until then, stay curious.