There are more than 1000 ants in the Boulder basement art gallery where Jacob Lemanski sits cross-legged, explaining how he got from biking across continents to building ant farms. All four walls ...

The ants tend to dig relatively straight tunnels that descend at the angle of repose – the slope at which a granular material naturally forms mounds – which was around 40 degrees in this case.

"We found that ant groups all dug tunnels of the same diameter, [no matter what the] ... "The state of the art search-and-rescue robotics is actually quite limited," he told the BBC.

By watching the ants burrow through glass tunnels, the researchers discovered that the optimal diameter of a fire-ant tunnel is roughly the same as a fire ant's body length.

Out of the great ant hill which is Manhattan, three sets of ant tunnels furrow under the Hudson River and emerge in the free air of New Jersey. One set of tunnels belongs to the Pennsylvania R. R ...