The viscous material on the spider web is a special material, called glue ball. It is not a simple adhesive mechanism. This sticky substance will transform into a solidified substance after subjected to mechanical stimulation. Any mechanical stimulus, including touch, will change its elements distribution. In the previous study, the distribution of monovalent metals, hydrochloride, and phosphate in the glue ball was reported. Phosphate groups are considered that play a key role in the

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... y of the glue ball. Here we report the distribution characteristics of divalent metal calcium in the glue ball. The calcium may be a key element for low-temperature sensing of the glue ball.