Effects of temperature on embryonic and larval growth and development in the rough-skinned newt (Taricha granulosa)


Meeting Abstract

P1-68  Sunday, Jan. 4 15:30  Effects of temperature on embryonic and larval growth and development in the rough-skinned newt (Taricha granulosa) SMITH, G.D.; HOPKINS, G.R.; HANSEN, T.T*; MOHAMMADI, S.; SKINNER, H.M.; BRODIE, JR., E.D.; FRENCH, S.S.; Utah State University hansen_cb_32@yahoo.com

Climate change is resulting in abnormal temperature regimes which can have major effects on ectotherms. In response to changing temperatures, wildlife can undergo alterations in their physiology and development in order to survive. Here we show the effects of temperature across embryonic and larval stages on the growth and development of the rough-skinned newt (Taricha granulosa). We randomly assigned newt eggs to different temperatures (7, 14, or 21˚C). After hatching, we randomly placed the newt larvae into three different temperatures. Over four weeks, we measured total length grown and the change in developmental stage. Our results indicate a strong positive correlation over time between temperature and both length and developmental stage. Individuals assigned to cooler embryonic temperatures did not grow as large as ones placed in higher temperatures during their embryonic development, even if they were placed in the same temperature during their larval development. This demonstrates the important carry-over effects of embryonic temperature. While there was an overall positive correlation between temperature and growth and development, larvae appeared to reach an upper limit at the warmest temperatures. Also, while larvae that developed embryonically in the coldest temperatures were unable to grow as large as larvae in the warmer temperatures, they were eventually able to reach the same developmental stage. Our investigation of plasticity and variability of responses to different temperatures along with life-stage carry-over effects, provides a more comprehensive understanding of how organisms respond when posed with temperature changes during development, a reality for most aquatic species.

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