蛛蜂用蚂蚁尸体保护巢穴

A new species of spider wasp¹, the 'Bone-house Wasp,' may use chemical cues from dead ants as a nest protection strategy, according to a recent study published July 2, 2014 in the open-access journal PLOS ONE by Michael Staab from University of Freiburg, Germany, and his colleagues from China and Germany. Wasps² use a wide variety of nest protection strategies, including digging holes or occupying pre-existing cavities such as in wood. Previous studies showed that the nests of cavity-nesting wasps contain several brood cells separated by thin walls of plant debris³, resin⁴（树脂，松香）, or soil. Once the females have finished constructing the nest, laying eggs, and providing food, they construct an outermost⁵ vestibular（前庭的） cell to close the nest. After construction, female wasps abandon the brood and do not care for their offspring anymore. Nest protection strategies play a central role in brood survival, and in this study, scientists interested in better understanding these strategies collected ~800 nests of cavity-nesting wasps with ~1900 brood cells belonging to 18 species in South-East China.   The scientists found a nesting behavior previously⁶ unknown in the entire animal kingdom: in over 70 nests they found an outer vestibular cell filled with dead ants. The species constructing these ant-filled vestibular cell was so far unknown to science and was described in the same study as the 'Bone-house Wasp' (Deuteragenia ossarium), after graveyard⁷ bone-houses or ossuaries. The scientists also found lower parasitism⁸ rates in "Bone-house" nests than in nests of similar cavity-nesting wasps. The authors suggest that D. ossarium nests are less vulnerable to natural enemies, potentially supporting the outer cell's role in defense⁹, which most likely involves chemical cues emanating¹⁰（散发，产生） from the dead ants used as nest-building material.   Dr. Staab added, "Our discovery demonstrates in an impressive way, what fascinating strategies of offspring-protection have evolved in the animal kingdom."