Biology in three dimensions

Most things in biology spread out into three dimensions, and many biological web sites include three-dimensional images. But biologists want more than a look at something. They want to pick it up and look at it from all sides, which is where three-dimensional images that can be manipulated online really come into their own. One approach to such interactive images relies on VRML (virtual reality modeling language), which allows you to zoom in and out on an image, rotate it, tilt it, nearly seem to pick it up. Luckily, cyber-surfers can leave most of the details to the programmers, but you cannot get the VRML experience with just any browser. You need either a VRML-capable browser or a VRML plug-in. Many of these can be obtained online and free of charge. You can find one at The VRML Repository, which also supplies an extensive collection of information on VRML as well as links to tutorials if you want to create your own images. Once you get VRML ready, point your browser to the VR fossils at the site of The Natural History Museum in London. This site gives you a taste of what VRML can do by letting you zoom in and out on two trilobites and a bryozoan. To move up to some fancier uses of VRML, visit a site called 3-D Insects, which provides models of more than a dozen insects. You can circle around these computer-generated bugs and take a look from virtually any range. This site also teaches one VRML-viewing requirement — patience. Even the small images can take a few minutes to load, especially from a home connection. If you really like these images, though, this site includes a short description of how to build them. And if you are really patient, look at the flying wasp. But once you click on it, make a cup of tea or take a catnap while it loads, otherwise you’ll be disappointed. Other VRML sites let you navigate inside three-dimensional space. When you first visit such sites, you might feel like an amateur tossed into an expert’s video-game arena. The screen often includes a control panel of instruments with little if any instruction about how to use them. Once you do figure out what a button does, it takes some time to get a feel for the controls. You might find yourself rocketing the image off one side of the screen and then the other. Once you’ve got the hang of it, visit the THOR Center for Neuroinformatics: Human Brain Project Repository. It provides a VRML link that takes you to many brain models, and you can seemingly ‘fly’ around inside some of them. A few of these brain models show areas activated by a behavior, such as tapping a finger. The activated area appears suspended in space, inside axes that represent the x, y and z planes of the brain, which show where the excited cells lie relative to the entire brain. This site also includes a gallery that’s like a poster session at a meeting, where you can navigate among the displays and take a closer look. You can delve more deeply into neuroscience at the VRML Biology Page. In one of this site’s sections, called Membrane Potential in Excitable Cells, you can watch the flow of ions during an action potential. Another section, called Membrane Channels, shows you a single sodium channel during an action potential. This demonstration follows a sodium ion all the way through the channel, taking you on a ride through a tiny tunnel in the cell membrane. Several VRML sites concentrate on the molecular level. At Web Molecules, you can examine three-dimensional ball-and-stick structures of amino acids, carbohydrates, lipids and many more molecules. For more realistic three-dimensional images, visit the Library of 3D Molecular Structures. It also supplies a wide range of molecules, and these images show the molecules as three-dimensional spheres of atoms clustered together. Although current VRML images of biology can intrigue and inform us, some of them creep so slowly onto your computer’s screen that they cannot possibly match expectations. Still, some of these images already give us a perspective we have never enjoyed before, and they are all the more exciting because they represent only a glimpse of the future. Watch this space.