make frogs grow extra legs
Two new studies of frogs in western
states give a big boost to parasites as an explanation of the widespread
Johnson, P.T.J., et al. 1999. The effect of trematode infection
on amphibian limb development and survivorship. Science 284(April
Sessions, S.K., R.A. Franssen, and V.L. Horner. 1999. Morphological
clues from multilegged frogs: Are retinoids to blame? Science
Burkhart, J.G., et al. 1998. Induction of mortality and malformation
in Xenopus laevis embryos by water sources associated with field frog
deformities. Environmental Health Perspectives 106(December):841.
Mlot, C. 1997. Water link to
frog deformities strengthened. Science News 152(Oct. 11):230.
A background, resources, and pictures of deformed frogs in Minnesota
can be found at http://www.pca.state.mn.us/hot/frogs.html.
Pieter T.J. Johnson
Claremont McKenna College
Roberts Environmental Center
W.M. Keck Science Center
925 North Mills Road
Claremont, CA 91711-5916
Stanley K. Sessions
Department of Biology
Oneonta, NY 13820
News, Vol. 155, No. 18, May 1, 1999, p. 277.
Copyright © 1999, Science Service.