Senses like sight, hearing, smell, taste, and touch have long been documented, and researchers have also pursued a growing notion of a sixth sense. magnetosensitivity is the term for the ability of some creatures to sense the Earth’s magnetic fields, helping them deduce their position and orientation, especially during migration. A new study indicates this magnetic sensing is more common than previously thought and may be present in a wide range of animals, potentially including humans.
For years, scientists have known that species such as the monarch butterfly, turtles, pigeons, and many others navigate using the planet’s magnetic field. This latest work builds on that understanding and shows how animals can stay on course even when facing the challenges of long journeys.
The paper, published in a leading journal, marks a significant advance in understanding how organisms detect and respond to magnetic fields. It also points toward new tools for measuring biological activity at the cellular level and how certain cells might be selectively influenced by magnetic stimuli.
Experiments with fruit flies and related species demonstrate, for the first time, that a molecule found in all living cells can reach magnetic susceptibility levels capable of affecting a biological system. The molecule is flavin adenine dinucleotide, commonly known as FAD.
The discovery underscores that the molecular machinery needed to sense magnetic fields is broadly present in living organisms, opening the possibility that many forms of life can perceive field lines and use them to determine positions, distances, and routes.
The fly that unlocks the mystery
Neuroscientist Richard Baines of the University of Manchester notes that our understanding of the five classical senses is strong, but it remains unclear which animals can detect magnetic fields and how they react. This new research contributes to filling that gap and highlights magnetosensitivity as a dynamic and active area of study.
The team describes how genetic mapping in fruit flies was used to test ideas about magnetic sensing. Although the fly looks very different from humans, its nervous system operates with similar basic principles, making it a useful model for exploring human biology and evolution.
Detecting magnetic fields proved challenging because magnetic fields carry far less energy than light or sound. Unlike the photons that accompany the other senses, magnetic fields interact with biology in subtler ways, demanding novel approaches and careful experimentation.
Researchers explore how living systems perceive magnetic information through quantum processes and through a light-sensitive protein known as cryptochrome found in many creatures. The idea is that light-driven reactions within cryptochrome can be influenced by magnetic fields, altering the protein’s activity in measurable ways.
A scientist explains that the absorption of light by cryptochrome can drive electron movements inside the protein, creating magnetic-sensitive states. The magnetic field then shifts the balance among these states, affecting the protein’s behavior and potentially the cell’s responses.
Environmental factors
One striking finding reveals that cells may detect magnetic fields even when only a small fragment of cryptochrome is present. This challenges current assumptions and suggests alternative pathways for magnetoreception under laboratory conditions.
Another important point shows that a widely distributed metabolic molecule can exhibit magnetic susceptibility without cryptochromes. FAD normally acts as a light sensor and often partners with cryptochromes to support magnetosensitive processes, but the study indicates FAD can play a direct role as well.
The researchers emphasize that their work has broad implications for understanding how environmental magnetic influences affect animal behavior and survival. Magnetosensitivity could shape how species navigate, respond to shifts in their environment, and endure evolving ecological pressures.
Authors suggest that magnetic interactions with FAD may trace back to evolutionary origins of magnetoreception, with cryptochrome evolving to exploit these magnetic effects on a common metabolic molecule. The study notes ongoing questions about how these findings translate to humans and what the long-term exposure to magnetic fields might mean for health and biology.
Because FAD and related cellular components appear across many tissues, the potential to leverage magnetic fields as a tool for biological manipulation is an exciting avenue for future research. Scientists are exploring how magnetic fields could become a powerful instrument in gene activation studies and other experimental applications.
In summarizing the work, the authors reference the Nature publication and emphasize the promise of these findings for a broader understanding of how magnetic fields influence living systems. The broader goal is to illuminate how environmental magnetic noise from technologies and natural sources affects animal behavior and physiology, and to identify any potential human implications.
Citation note: findings are reported in a Nature article from 2023. This summary presents the results and interpretations in a concise, accessible way while attributing the original research to its publication source.