The little architect with its marvelous creation- a study on the nest architecture of Tropical Hornet, Vespa affinis

Knowingly or unknowingly we are surrounded by many creatures which are specialized in building amazing structures with great finesse. It’s really wonderful to see how such tiny brains coordinate with each other to create perfect structure which is perhaps impossible for humans. On similar lines, the present study describes the nest architecture of tropical hornet, Vespa affinis built across several locations in Jalpaiguri district of West Bengal, India. Mature nests are roughly pear shaped, broadening from the top to truncate base. The architecture of the nest is in the pattern of a spiral staircase with a central and several auxiliary petioles supporting each of the comb layers. 2 large usually round entrance holes along with 6-7 small holes were also seen on the walls of the nest. Strikingly the hypertrophy of the nest envelope above the combs into a prominent roof cone with cellular structure is observed. Hardening of the nest texture and extensive papering over of the cells in the initial comb layers, thereby reducing their reutilization forms an essential feature of their nest. Several morpho-metric measurement of a typical nest (with 7 comb layers) from the study site was conducted. Each comb layers of the nests showed a rough bimodality of cell-diameter, with peaks at about 0.85 and 1.0 mm. The maximum number of occupied cells in the centre most stages of the nest (i.e. Comb layer 3) probably support the maximum number of brood members. The largest number of auxiliary petioles along with the tree branch provides greatest protection to the brood in this layer. Besides the highest number of petioles, the maximum number of unoccupied cells in comb layer 2 and 4 also provides extra protection to the developing brood in the comb layer 3. A decrease in the rate of nest building in the final stages (i.e. comb layer 6 and 7) is evident by the decrease in the number of cells in these layers.