Richard P. Elinson, Ph.D.

Developmental Biology

My laboratory asks how radical change in development can occur in evolution. Early mammalian embryos look similar to each other, as do those of birds and frogs and other groups. Yet, mammalian embryos look very different from bird embryos, which in turn do not look like frog embryos. If development within a group is similar, then how do differences between groups arise?

We are investigating the development of a very interesting frog, the Puerto Rican tree frog, Eleutherodactylus coqui. This frog develops differently from other frogs. It has a large egg that develops on land directly to a frog, without ever being a tadpole. We are investigating how this frog got rid of its tadpole, and whether this frog is following the similar evolutionary path that once gave rise to the reptiles, birds, and mammals.

This work is supported by grants from the National Institutes of Health (NIH) and the National Science Foundation (NSF).

A Coqui Serenade

The mating sounds of male coqui frogs from Dr. Elinson's lab have been captured and recorded as a Coqui Mating Call Ringtone and a Coqui Message Alert.

According to Dr. Elinson, only the male frogs sing: “Co” means “Stay away, fellows!” and “Qui” is the male frogs’ call for the female frogs to “Come hither!”

Read more about Dr. Elinson's Coqui frogs and their celebrated mating call at                                                               http://locallytoned.wordpress.com/2009/08/27/elinsons-coqui-tones/

1. Callery, E.M. and Elinson, R.P. (2000) Thyroid hormone-dependent metamorphosis in a direct developing frog. Proceedings of the National Academy of Science USA 97:2615-20.
2. Ninomiya H., Elinson R.P., Winklbauer R. (2004) Antero-posterior tissue polarity links mesoderm convergent extension to axial patterning. Nature 430: 364-367.
3. Nath, K., Boorech, J.L., Beckham, Y.M., Burns, M.M., and Elinson, R.P. (2005) Status of RNAs, localized in Xenopus laevis oocytes, in the frogs Rana pipiens and Eleutherodactylus coqui. J. Exp. Zool. (Mol. Dev. Evol.) 304B:28-39.
4. Buchholz, D.R., Karadge, U., Singamsetty, S., Williamson, S., Langer, C.E., and Elinson, R.P. (2007) Nutritional endoderm in a direct developing frog: a potential parallel to the evolution of the amniote egg. Developmental Dynamics 236:1259-1272.
5. Elinson, R.P., Walton, Z., Nath, K. (2008) Raldh expression in embryos of the direct developing frog Eleutherodactylus coqui and the conserved retinoic acid requirement for forelimb initiation. J. Exp. Zool. (Mol. Dev. Evol.) 310B:588-595.
6. Sabo, M.C., Nath, K., and Elinson, R.P. (2009) Lbx1 expression and frog limb development. Development Genes and Evolution 219:609-612.
7. Elinson, R.P. and Kezmoh, L. (2010) Molecular Haeckel. Developmental Dynamics 239:1905-1918.
8. Singamsetty, S. and Elinson, R.P. (2010) Novel regulation of yolk utilization by thyroid hormone in embryos of the direct developing frog Eleutherodactylus coqui. Evol Dev 12:437-448.
9. Elinson RP, Sabo MC, Fisher C, Yamaguchi T, Orii H, Nath K. 2011 Germ plasm in Eleutherodactylus coqui, a direct developing frog with large eggs. EvoDevo 2:20.
   (ePub - 11 pages, DOI: 10.1186/2041-9139-2-20)
10. Elinson RP, del Pino EM. 2012 Developmental diversity of amphibians. WIREs Developmental Biology 1:345-369 (DOI: 10.1002/wdev.23)

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Selected Journal Covers

Professor, Dept. of Zoology, University of Toronto 1985-2000
Assistant, Associate Professor, University of Toronto 1970-1985