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[Aim] Understanding patterns and processes of geographic genetic variation within and among closely related species is the essence of phylogeography. Japanese macaques, also called snow monkeys, have been extensively studied, particularly in the fields of sociobiology, ecology and experimental biology; however, our knowledge of their evolutionary history is relatively limited. In this study we aimed to elucidate the geographic patterns of genetic variation in Japanese macaques and the processes that underlie them. [Location] Japan. [Taxa] Japanese macaque, Macaca fuscata; rhesus macaque, M. mulatta; Taiwanese macaque, M. cyclopis. [Methods] Double-digest restriction site-associated DNA (RAD) sequencing was used to identify genome-wide single nucleotide variants. We used fineRADstructure, ADMIXTURE and principal component analyses to estimate the genetic population structure. Phylogenetic relationships were then inferred based on neighbour-net, neighbour-joining, maximum likelihood and SVDquartets algorithms. We assessed gene flow using demographic inference and ABBA-BABA tests, and estimated past distributions during the Last Glacial Maximum (LGM) using ecological niche modelling. [Results] Japanese macaques show a sister group relationship with a clade comprising Chinese rhesus, Indian rhesus and Taiwanese macaques. Japanese macaques comprise major north-eastern and south-western clades, with a boundary located near central Japan, and gene flow between the north-eastern and south-western lineages was detected. Refugia during the LGM were estimated to be distributed in limited areas along the south coasts of the Japanese archipelago. [Main conclusions] Phylogeographic variation of Japanese macaques is likely due mainly to northeast–southwest divergence, which resulted from withdrawal into refugia during the glacial period, and subsequent gene flow.

When rearing chicks, Leach’s storm-petrels (Oceanodroma leucorhoa) commute between foraging areas and breeding colonies with heavy food loads. At this time they should maximize the size of energy-supplying organs in response to increased energy expenditure but minimize total body mass to decrease the energetic cost of flight. Nineteen storm-petrels were killed to examine the changes in body composition and the masses of energy-supplying organs in birds that were incubating and rearing chicks. Parents lost a mean of 7.95 g in body mass between the stages of incubation and chick-rearing mainly via a loss of skin including subcutaneous adipose tissue, and a small fraction of heart and digestive organs, which are considered energy-supplying organs. This mass loss actually enables them to decrease flight cost by 14.4%. The benefits of decreasing flight costs by reducing total body mass are greater than if the energy-supplying organs of birds are enlarged only.

Milking under anesthesia in pregnant free-ranging Japanese macaques (Macaca fuscata) directly revealed lactation in gestation at Jigokudani Monkey Park, the Shiga Heights, Nagano Prefecture, Japan, from 12 to 14 February 1992. Multiparae secreted milk at 76-97 days of estimated fertilization age when the birth intervals to the next offspring were 2 years. The observation of sucking behavior from February 1991 to March 1992 indicated that concurrent suckling by these multiparae terminated approximately 70 days before the next parturition after the growth of fetuses had accelerated and the embryos survived the crisis of abortion. Thus, Japanese macaque mothers appear to hedge maternal investment with concurrent lactation against possible miscarriage. Two nulliparous pregnant females secreted milk 3 months before the first parturition although they had no suckers. The first preparation of lactation appears to require the duration of longer than 3 months in nulliparae although worked mammary glands appear to be able to resume within 1 month in multiparae. © 1993 Wiley-Liss, Inc.

An annual average of 163 Kuril seals was found dead in two years in salmon trap nets along the coastal waters of the Nemuro Peninsula and adjacent areas. The seal-caused damage to the total salmon catch at the salmon trap nets was concentrated in some of them, particularly No. 27, where seals killed or injured 5.1% of the catch in 1982, and 1.8% in 1983. Based on the proportion of Kuril seals among the dead seals in the trap nets, it was estimated that Kuril seals damaged 4.7% of the total salmon catch at No. 27 in 1982, and 1.7% in 1983. Not all seals that entered the trap net drowned; some killed or damaged salmon, and then escaped.