HORNETS glue tiny magnetic crystals into the roofs of the hexagonal cells
that they build for brood-rearing, biologists have found.
Jacob Ishay of Tel Aviv University in Israel and his colleagues at the
University of Groningen in the Netherlands found fine fibre “veins” that
gathered at the centre of the cell roofs.
“We thought there must be something connecting these fibres in the middle,”
says Ishay. When they looked closer, they found each cell roof contained a
crystal of magnetic iron titanium oxide measuring a tenth of a millimetre
across.
“These tiny crystals form a network that may act like a surveyor’s spirit…
