FROM THE EDITOR
Curiosity Expands our Worldview
As spring approaches, tiny parasites take positions atop dangling tree branches and wait for their hosts. These creatures, both blind and deaf, experience the world as a minuscule place, one that consists primarily of their immediate physical environment. Despite these limitations, ticks are equipped to sense changes in temperature as well as the presence of butyric acid, a chemical found in animal sweat.
For as long as it takes they await the warmth and scent of an approaching animal. Then, each one drops from its resting place, hoping to score a fresh meal. A successful dismount places the lucky ones millimeters away from their bounty. They burrow into the skin of their victims to guzzle the nutrient-rich blood just below the surface. Once engorged, they plummet to the ground, lay their eggs, and die.
By human standards it may seem a sad and lonely life. These tiny arachnids are largely unaware of the woodland biosphere around them. They miss out on the lush greenery of the forest canopy, the calming cadence of a nearby stream, and the earthy aroma of decomposing tree bark. But this wistful notion is based on my own decidedly human perspective. The tick, having fulfilled its destiny, is in no position to question its obliviousness.
In 1909, German biologist Jakob von Uexküll introduced the concept of the umwelt, the subset of environmental factors detected by an animal in its natural setting. He observed that animals inhabiting the same ecosystem could have strikingly different perceptions of the world. For any given species, the entirety of its universe consists solely of the stimuli it encounters. The larger reality, called the umgebung, may not be known to the animal.
Humans enjoy a robust sensory toolkit for detecting our physical world. Nevertheless, some aspects of our environment elude our senses, such as ultraviolet light, infrasound, and x-rays. It took the keen observations and ingenuity of exceptionally curious individuals to develop sensors and assays to verify the existence of these phenomena and to open new frontiers to explore.
Today, we’ve modified our worldview, expanding it to accommodate as-yet unproven concepts such as dark energy and the multiverse. And with increasing awareness of the peculiar nature of our known universe, we’re able to imagine new and different physical realities. To fully grasp the limits of our umgebung, we must first acknowledge what we know and what we don’t.
In this issue’s Perspective column, “A New Window on Alien Atmospheres”, Kevin Heng explains how the James Webb Space Telescope will increase our capacity to analyze the atmospheric composition of distant alien worlds, an idea once considered to be ludicrous; in “The Biodiversity Conservation Paradox”, Mark Vellend describes the perceptual challenge of measuring ecosystem losses even as the number of species in an area increases or remains unchanged; in the Computing Science column, “How to Detect Faked Photos”, Hany Farid teaches us the art of recognizing distortions and manipulations in the photographic data that reveal the world to us; and in “Risks and Benefits of Radiation”, Timothy Jorgensen shares a cautionary tale about the invisible contaminant radon and its effects on us. Each of these authors conveys the importance of being aware of our sensory strengths and deficits and emphasizes how these faculties contribute to a rich life.
Recent political events remind us that, beyond our physical environment, we also exist within a cultural umwelt, which is the product of social stimuli. It can be all too easy sometimes to limit our focus within this social world, growing preoccupied with our usual confines until, like the tick, we become blind to the dazzling complexity of our ecosystem. But, if our physical universe is a cue, imagine the cultural possibilities that might be discovered through a little social curiosity. —Jamie L. Vernon (@JLVernonPhD)