Abiotic factors and biotic interactions, such as interspecific competition, are fundamental determinants of animal growth and survival. However, comprehensively and quantitatively assessing the impacts of interspecific competition while accounting for confounding abiotic factors remains a challenge in ecological research. We investigated changes in the ecological and morphological characteristics of southern Asian Dolly Varden...

Longitudinal distribution and niche partitioning phenomena have been extensively reported for streams containing two salmonid species but remain poorly understood for streams containing three or more salmonid species. Herein, we examined the abiotic environmental variables and population densities of fishes, including three salmonids, in 30 reaches of the Setose River, Hokkaido, Japan, across altitudes (120–450 m) and maximum...

Tetrodotoxin (TTX), known as pufferfish toxin, is a potent neurotoxin blocking sodium channels in muscle and nerve tissues. TTX has been detected in various taxa other than pufferfish, including marine polyclad flatworms, suggesting that pufferfish toxin accumulates in fish bodies via food webs. The composition of TTX and its analogs in the flatworm Planocera multitentaculata was identical to those in wild grass puffer Takifug...

Summary DnaA activity for replication initiation of the E scherichia coli chromosome is negatively regulated by feedback from the DNA ‐loaded form of the replicase clamp. In this process, called RIDA (regulatory inactivation of DnaA ), ATP ‐bound DnaA transiently assembles into a complex consisting of Hda and the DNA –clamp, which promotes inter‐ AAA + domain association between Hda and DnaA and stimulates hydrolysis of DnaA ‐...