〓 Research Area : Forest Ecology

Effects of intermittent reproduction on forest
regeneration in Fagus crenata
Fagus crenata is one of the characteristic tree species that produces
a large amount of flowers and seeds every few years. Environmental
factors, such as temperature and nutrient content, play a role in thisintermittent reproduction mechanism, but it is not clear how seed production will be affected by recent climate change. Seed production is
not only an important factor underpinning forest regeneration, but it
also provides food for the diverse organisms that survive within forest
ecosystems. We are attempting to clarify how this intermittent reproduction contributes to seedling regeneration through analysis basedon long-term surveys.

Study on the mechanism of environmental flower sex
determination in plants and its adaptive significance〓 Assoc. Prof.
MIYAZAKI Yuko

More than 90% of all seed plants do not havesex chromosomes and produce a combination ofhermaphroditic, female, and male flowers in an
individual plant. However, the sex determination
mechanism of individual flowers remains unclear
and how environmental factors (e.g., day length,
temperature, and nutrient status) act on sex determination. We are trying to elucidate the mechanisms of environmental factors, especially shortday conditions and nutrient status, that induce
hermaphroditic flower in relation to flower initiation,using Commelina communis f. ciliata. We also
examine the adaptive significance of these environmental conditions as signals of floral sex determination and attempt to predict future climate change impacts.

〓 Research Area : Insect Ecology

Study on ecological genetics of fruit flies
Insects are the most prosperous creatures on earth
with very diverse ecological traits. Many researchers
are trying to elucidate how insects adapt to wide-range
of environments Among such insects, Drosophila flies
have been studied as a model organism for about 100years mainly in the fields of genetics and developmental biology. At present, it has become a very useful
research material in the fields of ecology and evolutionary biology due to the accumulation of knowledge
and various study resources such as mutant strains.
This research unit mainly uses Drosophila flies as a
research material, and is engaged in elucidating thegenetic basis of various traits and conducting ecological research.

〓 Assoc. Prof.
TAKAHASHI Kazuo

One of the latest research topics of thisresearch unit is WIPs (Wing InterferencePatterns). WIPs are known in wings of small
Dipteran and Hymenopteran insects especially when observed on dark background.
Although WIPs are extremely stable traits andhave been suggested to be a useful trait for
species classification, quantification methods
have not yet been established. Currently,
WIPs are utilized only as a visual phenotype
based on human vision. However, WIPs,
which reflect the fine physical structure of thewing, may retain a large amount of information on genetic variation in the wing morphogenesis process. We are trying to establish a new
method to quantify WIPs and investigate the genetic basis of WIPs.

Graduate School of Environmental and Life Science, Okayama University25