New Scientist has a great set of stories about the extraordinary senses of animals, including the fact that creatures like sea turtles can sense the Earth's magnetic field and use it for navigation.
Young loggerhead turtles, for example, read the Earth's magnetic field to adjust the direction in which they swim. They seem to hatch with a set of directions, which, with the help of their magnetic sense, ensures that they always stay in warm waters during their first migration around the rim of the North Atlantic. Over time they build a more detailed magnetic map by learning to recognise variations in the strength and direction of the field lines, which are angled more steeply towards the poles and flatter at the magnetic equator.
What isn't known, however, is how they sense magnetism. Part of the problem is that magnetic fields can pass through biological tissues without being altered, so the sensors could, in theory, be located in any part of the body. What's more, the detection might not need specialised structures at all, but may instead be based on a series of chemical reactions.
Even so, many researchers think that magnetic receptors probably exist in the head of turtles and perhaps other animals. These might be based on crystals of magnetite, which align with the Earth's magnetic field and could pull on some kind of stretch receptor or hair-like cell as it changes polarity. The mineral has already been found in some bacteria, and in the noses of fish like salmon and rainbow trout, which also seem to track the Earth's magnetic field as they migrate.
Via Nicola Twilley
Image: Loggerhead Turtle, a Creative Commons Attribution (2.0) image from coda's photostream
Since its publication in late 2015, science writer Oliver Morton’s The Planet Remade: How Geoengineering Could Change the World has swept many “best book” (best science book, best business book, best nonfiction book) and with good reason: though it weighs in at a hefty 440 pages and covers a broad scientific, political and technological territory, few science books are more important, timely and beautifully written.
After years of speculation and wrangling over his remains, Kennewick Man turns out to be closely related to contemporary, local Native Americans after all. Discovered near Kennewick, Wash., in 1996, the skeleton ended up in a tug of war between tribes in the pacific northwest who wanted to bury the remains, and scientists who wanted […]
Our solar system is awesome.
Why buy one of those expensive and confusing universal remotes, clogged with enough buttons to launch a space shuttle, when you could accomplish the same electronic control right on your favorite mobile device? The Blumoo Universal Remote, now just $52.99 in the Boing Boing Store, harnesses the audio power of all your household equipment right […]
You may not love Microsoft Word, but you’ve definitely used it. Other than being one of the most ubiquitous programs on the planet, it’s been the go-to word processing system for more than a quarter-century because it’s as basic as it gets. But occasionally, you’ve got assignments that beg for a lot more options than simple […]
Almost everyone has their smartphone in a case of one kind or another. Beyond simple protection, finding a case that can charge your phone on its own, but doesn’t feel like it’s also adding a couple pounds to the phone’s weight is the tricky part. Billed as the world’s thinnest battery case, the ThinCharge iPhone […]