Emergent and effective properties in ecology and evolution

Emergent properties are often discussed in arguments concerning relationships among different levels. However, the different definitions of emergent properties sometimes confuse the arguments about macro-level phenomena, since some authors regard emergent properties not only as observable global patterns but as properties that affect and cause change in ecological and evolutionary processes. Thus it is important to distinguish higher-level or larger-scale properties that can influence particular ecological and evolutionary processes from those that cannot. I call the former properties effective properties. I gave examples that show why the distinctions between effective and non-effective properties are important.     

Relationship between state anxiety and success rate in game performance, coach's evaluation among Japanese university volleyball players

The purpose of this study is to examine the relationship between state anxiety and individual athletic game performance. The subjects were 54 male players of 4 teams (The average age was 20.5 (SD=1.09) years), who participated in the Kanto university men's volleyball league games in the spring of year 2010. The subjects were asked to respond to a Japanese version of the State Trait Anxiety Inventory (STAI), which was measured at 4 time periods (the day before, the day of game, just before the game, just after the game) for each of a total of 40 games (each team played 10 games). The results were as follows: (1) Relationships between state anxiety and success rate in game performance (spike, reception, block) showed different correlation depending on each game performance. (2) The group of players who performed well in games collected by coaches scored lower than the more badly-performing group in the score of state anxiety on the day of game and just after the game. (3) The temporal change of the score of state anxiety from just before the game to just after the game was different depending on whether they performed well or not in games.     

Loss of genetic variability in a fragmented continuously distributed population

An individual-based simulation model was used to examine the effect of population subdivision, dispersal distance of offspring, and migration rates between subpopulations on genetic variability(H ₁ H _S andH _T ) in a continuously distributed population. Some difficulties with mathematical models of a continuously distributed population have been pointed out. The individual-based model can avoid these difficulties and can be used to examine genetic variability in a population within which individuals are distributed continuously and in which the dispersal of individuals is disturbed by geographical or artificial barriers. The present simulation showed that the pattern of decrease inH ₁ had three stages. During the first stage,H ₁ decreased at the rates predicted by Wright’s neighborhood size. During the second stage,H ₁ decreased more rapidly when the migration rate decreased, while during the third stage, it decreased less rapidly when the migration rate decreased. Increasing the number of subdivisions increased the rate of decrease after the 200th generation. The pattern of decrease inH _T was classified into 2 stages. During the first stage, the rates of decrease corresponded with those of a randomly mating population. During the second stage, a decrease in the migration rates of the subpopulations slowed the rate of decrease inH _T . A uniform spatial distribution and a reduced total dispersal distance of offspring causedH ₁ H _S , andH _T to decrease more rapidly. Habitat fragmentation in a continuously distributed population usually was detrimental to the genetic variability in the early generations. Other implications of the results for conservation are discussed.     

Social organization of the voleClethrionomys rufocanus and its demographic and genetic consequences: A review

Recent findings on the relationship between social interaction and demographic process in the gray-sided voleClethrionomys rufocanus are reviewed with reference to the findings in other microtine rodents. Social behavior was particularly focused on spacing and dispersal, and their effects on population dynamics are discussed. Female territoriality can limit a population abundance as a density-dependent factor, although its regulatory effect is controversial. Female philopatry and male-biased dispersal should bring about the clumped distribution of female relatives and genetically random distribution of males during the breeding season. The sexual difference in dispersal patterns can contribute to the mating behavior of the vole; promiscuous mating and low frequency of incestuous mating. However, effects of social structure, including kinship, on reproduction and survival of individuals still remains to be clarified. Molecular markers may help to solve these issues and provide new field of population ecology in microtine rodents.     

Mind reading through the eyes: an fMRI study

Mind reading is the ability to understand another person's thoughts, intentions, and feelings (Whiten, 1991). The purpose of this study was to clarify which part of the brain is evoked while mind reading in functional Magnetic Resonance Imaging (fMRI) experiments, using a mind reading task, the Reading Mind in the Eyes Test (RME: Baron-Cohen et al., 2001) with four choices (mental state words). The participants were right-handed and sex-matched healthy Japanese university students (10 males and 10 females, age range 19-25). We used periodic ABA...block design in the fMRI sessions. Task A (an experimental task) was the mind reading task and Task B (a control task) was the age-gender task. In order to clarify the activated region of the brain while mind reading, we calculated the difference between the degrees of BOLD (Blood-oxygen-level dependent) activation during the Task A and Task B. The results showed that there was a significant difference in activation of the right superior occipital gyrus, and the left parietal lobe. These findings indicated that these regions were used while mind reading. The role of these regions was discussed in terms of the findings from previous studies.     

Relative importance of direct and indirect interaction among individual snails

Summary Individual organisms interact directly through behavior, and indirectly through resource consumption and environment modification. The effects of different kinds of interactions on individual growth and reproduction will differ. Freshwater snails may interact directly for food resources and indirectly through substances dissolved in water. I separated the effects of the direct behavioral interaction and indirect interaction through waters using laboratory experiments with freshwater snailsPhysa acuta. Behavioral direct interaction have negative effects on the growth, but indirect interaction through water environments has positive effect on the growth. The importance of distinction of different kinds of interactions were discussed.