SICB Annual Meeting 2008

Symposium: "Consequences of maternally-derived yolk hormones for offspring: current status, challenges and opportunities"

(Organized by R. Bowden & M. Lovern)

Information about Complementary Session


Mothers can influence the phenotype of their offspring in ways beyond the genes that are transferred. Such maternal effects are widespread, and continuing research demonstrates just how subtle and profound they can be. There is tremendous interdisciplinary interest in maternal effects because of their evolutionary implications.

Despite the explosion of research on this topic and the apparent ubiquity of maternal steroid distribution in oviparous taxa, several key, inter-related questions remain unanswered, including: Why are steroids transferred to yolk? Does maternal steroid deposition represent an adaptive mechanism for the manipulation of offspring phenotype, or is it the by-product of female reproductive physiology? What are the long-term consequences of yolk steroid exposure, if any, to the offspring?

Many studies report positive effects of maternal steroids on offspring development, however several studies indicate that maternally deposited steroids can result in negative consequences for developing offspring. It seems likely that the effects of yolk steroids on offspring development are complex, may be positive or negative depending on the traits examined, and that they differ both within and among taxa. To date, however, there have been limited interactions between researchers studying this phenomenon in different taxa and so whether or not large-scale patterns regarding the function of yolk steroids in offspring development occur is unknown.

The first objective of this symposium is to bring together researchers who are working with a variety of taxonomic groups to facilitate a more synthetic approach to our understanding of the effects of yolk steroids. The second objective is to encourage collaboration among researchers by identifying common themes that bridge across taxonomic boundaries. The third objective is to identify areas - both taxonomic and phenomenological - in need of further research.


Rachel M. Bowden
Assistant Professor
Department of Biological Sciences Illinois State University Normal, IL 61790-4120 USA Phone: (309) 438-3834 Fax: (309) 438-3722 Email: Web: Bowden/

Matthew B. Lovern
Assistant Professor
Department of Zoology
Oklahoma State University
Stillwater, OK 74078 USA
Phone: (405) 744-5551
Fax: (405) 744-7824
Web: http://zoology. zoo_fclt/ mlovern.htm

Support Provided By:


National Science Foundation - Integrative Organismal Systems ( div/index.jsp?div=IOS)

List of speakers:

S5-1.1 Fri, Jan. 4, 08:30 ADKINS-REGAN, E*; VAN VEEN, SC; JOHNSON, P: Maternal Yolk Steroid Effects on Offspring: Questions and Answers from Galliform Birds

S5-1.2 Fri, Jan. 4, 09:00 LOVE, Oliver/P*; WILLIAMS, Tony/D: Corticosterone as a maternal effect: variability within- and between-species and speculations on links to fitness

S5-1.3 Fri, Jan. 4, 09:30 SCHWABL, Hubert*; MARTIN, Thomas E.: Hormone-mediated maternal effects in birds evolution of mechanisms

S5-1.4 Fri, Jan. 4, 10:30 BOWDEN, RM*; PAITZ, RT: Patterns of yolk steroid decline during incubation and potential effects on offspring in species with temperature-dependent sex determination

S5-1.5 Fri, Jan. 4, 11:00 RIPLEY, Jennifer L.; FORAN, Christy M.*: Consider the Timing, Consider the Source Lessons from the Comparative Responses of Teleosts.

S5-1.6 Fri, Jan. 4, 11:30 LOVERN, M.B.*; ADAMS, A.L.: Yolk steroids in the green anole, a lizard with genotypic sex determination: exploring the environment-mother-offspring link

S5-2.1 Fri, Jan. 4, 13:30 WIDDER, P.D.*; BELDEN, L.K.: Maternally-derived steroids in amphibian eggs

S5-2.2 Fri, Jan. 4, 14:00 MOORE, Michael*; JOHNSTON, Gwynne: Toward a Dynamic Model of Yolk Steroid Deposition and Utilization

S5-2.3 Fri, Jan. 4, 14:30 GROOTHUIS, T G G *; SCHWABL, H: Hormone-mediated Maternal Effects in Birds: Mechanisms


In addition to the full day symposium, there is a complementary session OPEN TO ALL PRESENTERS with yolk steroid-related research. We encourage broad participation in this session, and if interested, be sure to select our symposium under Section F ("Topics of sessions") of the Abstract Submittal Form ( meetings/2008/ abstracts/index.php3).

Photo courtesy of Ryan Paitz and Rachel Bowden

Photo courtesy of Oliver Love and Tony Williams

Photo courtesy of Ryan Paitz and Rachel Bowden

Photo courtesy of Pam Widder

Photo courtesy of Jennifer Ripley and Christy Foran

Photo courtesy of Matt Lovern