title: K+ excretion: the other purpose for puddling behavior in Japanese Papilio butterflies.
abstract: To elucidate the purpose of butterfly puddling, we measured the amounts of Na+, K+, Ca2+, and Mg2+ that were absorbed or excreted during puddling by male Japanese Papilio butterflies through a urine test. All of the butterflies that sipped water with a Na+ concentration of 13 mM absorbed Na+ and excreted K+, although certain butterflies that sipped solutions with high concentrations of Na+ excreted Na+. According to the Na+ concentrations observed in naturally occurring water sources, water with a Na+ concentration of up to 10 mM appears to be optimal for the health of male Japanese Papilio butterflies. The molar ratio of K+ to Na+ observed in leaves was 43.94 and that observed in flower nectars was 10.93. The Na+ amount in 100 g of host plant leaves ranged from 2.11 to 16.40 mg, and the amount in 100 g of flower nectar ranged from 1.24 to 108.21 mg. Differences in host plants did not explain the differences in the frequency of puddling observed for different Japanese Papilio species. The amounts of Na+, K+, Ca2+, and Mg2+ in the meconium of both male and female butterflies were also measured, and both males and females excreted more K+ than the other three ions. Thus, the fluid that was excreted by butterflies at emergence also had a role in the excretion of the excessive K+ in their bodies. The quantities of Na+ and K+ observed in butterfly eggs were approximately 0.50 μg and 4.15 μg, respectively; thus, female butterflies required more K+ than male butterflies. Therefore, female butterflies did not puddle to excrete K+. In conclusion, the purpose of puddling for male Papilio butterflies is not only to absorb Na+ to correct deficiencies but also to excrete excessive K+.
authors.affiliation: Japanese National Institute of Agrobiological Sciences, Ôwashi 1-2, Tsukuba, Ibaraki, 305-8634, Japan.
authors.forename: Takashi A
authors.initials: TA
authors.lastname: Inoue
authors.affiliation: Kibougaoka 34-19, Asahi, Yokohama, Kanagawa, 241-0624, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Ito
authors.affiliation: Department of Natural Science, Faculty of Knowledge Engineering, Tokyo City University, Tamatudzumi, Setagaya, Tokyo, 158-8557, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hagiya
authors.affiliation: Japanese National Institute of Agrobiological Sciences, Ôwashi 1-2, Tsukuba, Ibaraki, 305-8634, Japan.
authors.forename: Tamako
authors.initials: T
authors.lastname: Hata
authors.affiliation: Japanese National Institute of Agrobiological Sciences, Ôwashi 1-2, Tsukuba, Ibaraki, 305-8634, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Asaoka
authors.affiliation: Division of Biology, Department of Earth System Science, Faculty of Science, Fukuoka University, Shichikuma 8-19-1, Jounan, Fukuoka, Fukuoka, 814-0180, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Yokohari
authors.affiliation: Department of Natural Science, Faculty of Knowledge Engineering, Tokyo City University, Tamatudzumi, Setagaya, Tokyo, 158-8557, Japan.
authors.forename: Kinuko
authors.initials: K
authors.lastname: Niihara
mesh_terms: D000818:Animals; D002080:Butterflies / Q000502:physiology*; D002118:Calcium / Q000032:analysis; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D008274:Magnesium / Q000032:analysis; D008297:Male; D018515:Plant Leaves / Q000737:chemistry; D011188:Potassium / Q000032:analysis*; D012964:Sodium / Q000032:analysis; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D012964:Sodium; D008274:Magnesium; D011188:Potassium; D002118:Calcium