The Fiji ant plant, Squamellaria, has long been studied for its remarkable ability to form symbiotic relationships with ants. But what makes this relationship truly unique is the way the plant provides separate “condos” for each ant species, preventing conflicts that could arise from competition for resources. Researchers from Washington University in St. Louis and Durham University in the United Kingdom have made a groundbreaking discovery about the secrets behind this harmonious coexistence.

The study, published in Science, reveals that compartmentalization is the key to mitigating conflicts between unrelated symbionts. By creating separate chambers within its tubers, Squamellaria prevents ant colonies from coming into contact with each other, thereby reducing competition for resources and eliminating deadly conflicts.

“We were able to visualize directly what theory has long predicted – that unrelated partners would conflict by competing for host resources,” said Susanne S. Renner, senior author of the study. “But here we also have a simple, highly effective evolutionary strategy to mitigate these conflicts: compartmentalization.”

The researchers used computed-tomography scanning and 3D modeling to visualize the tubers’ internal structure and understand how the plant enables multiple ant species to live together in harmony. They found that removing the partition walls between the chambers resulted in immediate conflict and high worker mortality, emphasizing the importance of compartmentalization.

This discovery has significant implications for our understanding of symbiotic relationships and the ecology and evolution of species interactions. It highlights the remarkable ability of Squamellaria to adapt to its environment and form mutually beneficial relationships with ants, even when faced with conflicting interests.

The study’s findings also shed light on a long-standing problem in ecological theory – how unrelated partners can form long-term mutualistic relationships despite competing for host resources. By providing separate compartments, Squamellaria has evolved an effective solution to this problem, allowing multiple ant species to coexist peacefully and benefiting from each other’s presence.

In conclusion, the tiny condos of Fiji’s ant plant have unlocked a secret to harmonious coexistence among unrelated symbionts, offering new insights into the complex relationships between species.

The future of sustained space habitation relies heavily on our ability to grow fresh food away from Earth. The Moon-Rice project is a groundbreaking initiative that uses cutting-edge experimental biology to create an ideal future food crop for deep-space outposts and extreme environments back on Earth.

Resupplying food from Earth has been the norm in modern space exploration, but this often comes with pre-prepared meals that rarely contain fresh ingredients. To combat the negative effects of space travel on human health, a reliable source of food rich in vitamins, antioxidants, and fibers is crucial.

The Moon-Rice project aims to develop the perfect crop for sustaining life in space for long-duration missions, such as permanent bases on the Moon or Mars. Dr. Marta Del Bianco, a plant biologist at the Italian Space Agency, explains that one of the major challenges is the current size of crops grown on Earth, even dwarf varieties being too large to be grown reliably in space.

To address this issue, researchers are isolating mutant rice varieties that can grow to just 10 cm high, maximizing production and growth efficiency by altering plant architecture. Additionally, since meat production will be too inefficient for resource- and space-limited space habitats, Dr. Del Bianco’s team is exploring ways to enrich the protein content of the rice.

The Moon-Rice project is not a solo effort but rather a collaborative initiative between three Italian Universities: the University of Milan, Rome ‘Sapienza’, and Naples ‘Federico II’. This four-year project has already shown promising preliminary results.

Dr. Del Bianco’s personal focus is on how the rice plants will cope with micro-gravity. She simulates micro-gravity conditions on Earth by continually rotating the plant so that it doesn’t know where the up and down is. This is the best they can do on Earth, as doing experiments in real microgravity conditions in space is complex and expensive.

Not only can fresh food be more nutritious than pre-cooked and packaged space meals, but it also has significant psychological benefits too. Watching and guiding plants to grow is good for humans, and while pre-cooked or mushy food can be fine for a short period of time, it could become a concern for longer-duration missions.

Space exploration requires astronauts to be in peak physical and psychological condition. If we can make an environment that physically and mentally nourishes the astronauts, it will reduce stress and lower the chances of people making mistakes. In space, the best-case scenario of a mistake is wasted money, and the worst-case scenario is the loss of lives.

The Moon-Rice project has applications beyond space exploration, too. If we can develop a robust crop for space, it could be used at the Arctic and Antarctic poles, or in deserts, or places with only a small amount of indoor space available.

This research will be presented at the Society for Experimental Biology Annual Conference in Antwerp, Belgium on July 9th, 2025.

MIT scientists have made a groundbreaking discovery in boosting the efficiency of an essential enzyme that powers all plant life – rubisco. By using a directed evolution technique, they were able to enhance a version of rubisco found in bacteria from low-oxygen environments by up to 25 percent. This breakthrough has significant implications for improving crop yields and reducing energy waste in plants.

The researchers used a newer mutagenesis technique called MutaT7, which allowed them to perform both mutagenesis and screening in living cells, dramatically speeding up the process. They began with a version of rubisco isolated from semi-anaerobic bacteria known as Gallionellaceae, one of the fastest rubiscos found in nature.

After six rounds of directed evolution, the researchers identified three different mutations that improved the rubisco’s resistance to oxygen and increased its carboxylation efficiency. These mutations are located near the enzyme’s active site, where it performs carboxylation or oxygenation.

The MIT team is now applying this approach to other forms of rubisco, including those found in plants. Plants lose about 30 percent of the energy from sunlight they absorb through a process called photorespiration, which occurs when rubisco acts on oxygen instead of carbon dioxide.

“This really opens the door to a lot of exciting new research, and it’s a step beyond the types of engineering that have dominated rubisco engineering in the past,” said Robert Wilson, a research scientist in the Department of Chemistry. “There are definite benefits to agricultural productivity that could be leveraged through a better rubisco.”

The research was funded by several organizations, including the National Science Foundation and the Abdul Latif Jameel Water and Food Systems Lab Grand Challenge grant.

This breakthrough has significant implications for improving crop yields and reducing energy waste in plants. The researchers’ directed evolution technique allows them to look at a lot more mutations in the enzyme than has been done in the past, making it a compelling demonstration of successful improvement of a rubisco’s enzymatic properties.