High levels of fluctuating asymmetry in populations of Apodemus flavicollis from the most contaminated areas in Chornobyl
Taras
K. Oleksyk a,b,c,*, James M. Novak a,b, James R.
Purdue d, Sergiy P. Gashchak e, Michael H. Smith
a,b
aThe University of Georgia's, Savannah River Ecology
Laboratory, Drawer E. Aiken, SC 29802, USA
bInstitute of Ecology, The University of Georgia, Athens, GA.
30602, USA
c Laboratory of Genomic Diversity, National Cancer Institute,
NIH, Frederick, MD, USA
dIllinois State Museum, 1011 East Ash St., Springfield, IL
62703, USA
eInternational Radioecology Laboratory, Slavutych 07100, Ukraine
Received 30 April 2003; received in revised form 30 July 2003; accepted
30 July 2003
Abstract
Random deviations
from the perfect symmetry of normally bilaterally symmetrical characters
for an individual with a given genotype occur during individual development
due to the influence of multiple environmental factors. Fluctuating asymmetry
(FA) is often used as a measure of developmental instability, and can
be estimated as the variance of the distribution of differences between
the left and right sides. We addressed the question of whether levels
of FA were elevated in radioactively contaminated populations living around
Chomo- byl compared to those in reference populations of the yellow-necked
mouse (Apodemus flavicollis). In addition, we studied amounts
of directional asymmetry (DA) when one side is larger than the other on
average. There was a significant difference among populations, including
reference populations, in the amount of both FA and DA. A higher level
of FA was documented for the contaminated populations in close proximity
to the failed Chornobyl reactor for both the asymmetry of size and shape.
The F As of size and shape were high- est in populations from the most
contaminated locations in the Chornobyl exclusion zone. Although the directional
asymmetry of shape was also highest in the contaminated populations, it
was not significantly different from those in most of the reference populations.
Populations from less contaminated areas inside the Chornobyl exclusion
zone did not express FA values different from those of the reference populations
outside the affected area.
SREL Reprint #2730
Oleksyk, T. K., J. M. Novak, J. R. Purdue, S. P. Gashchak and M. H. Smith. 2004. High levels of fluctuating asymmetry in populations of Apodemus flavicollis from the most contaminated areas in Chornobyl. Journal of Environmental Radioactivity 73:1-20.
