title: Magnetic minerals. Keystone-like crystals in cells of hornet combs.
abstract: The hexagonal brood-rearing cells inside the nest combs of the hornet Vespa orientalis are uniform in both their architecture and orientation. We have discovered that each cell contains a minute crystal that projects down from the centre of its domed roof and has a composition typical of the magnetic mineral ilmenite. These tiny crystals form a network that may act like a surveyor's spirit-level, helping the hornets to assess the symmetry and balance of the cells and the direction of gravity while they are building the comb.
authors.affiliation: Department of Cell Biology, Faculty of Medical Sciences, Graduate School of Brain Cognition and Neurosciences, University of Groningen, Oostersingel 69-2, 9713 EZ Groningen, The Netherlands. physio7@post.tau.ac.il
authors.forename: I
authors.initials: I
authors.lastname: Stokroos
authors.forename: L
authors.initials: L
authors.lastname: Litinetsky
authors.forename: J J
authors.initials: JJ
authors.lastname: van der Want
authors.forename: J S
authors.initials: JS
authors.lastname: Ishay
mesh_terms: D000818:Animals; D003460:Crystallization; D006112:Gravitation; D007501:Iron / Q000032:analysis*; D008280:Magnetics; D009425:Nesting Behavior; D014025:Titanium / Q000032:analysis*; D014863:Wasps
chemical_list: C029232:ilmenite; D014025:Titanium; D007501:Iron