Animals live their lives in three dimensions. By incorporating data from the third, vertical dimension - elevation, altitude, or depth - scientists can finally have a more accurate understanding of how animals move.
Flatland: A Romance of Many Dimensions was an 1884 parable written to satirize the hierarchies of Victorian culture, but it also provides a fascinating, intuitive understanding of what happens when you move from a 2D world to a 3D one. Most studies of the way that animals move around their habitats have limited themselves to a 2D description, relegating the critters to locations found along the North-South and East-West axes. But for species that fly, dive, climb, or burrow, that third up-and-down dimension is pretty critical. Animals don't live in Flatland, after all.
GPS loggers, an increasingly invaluable component in the wildlife biologist's toolkit, collect data from all three axes - X, Y, and Z - along with time. The problem is, most visualization software strips out that Z component, compressing rich volumetric data onto a flat sheet. Imagine wearing your 3D goggles at a movie, but watching through only one eye. What a waste!
USGS biologist Jeff Tracey and colleagues have created new modeling and visualization procedures to account for that third dimension. Here, see a visualization of the 3D space usage of a California condor breeding pair for each day over nearly five years. The bottom panes show the movements of the male and female individually. The top left combines the two into a single visualization, and the top right shows the motion trajectories for the pair.
Header image: California condor, public domain.