Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki, Helsinki, Finland.
J Evol Biol. 2011 Jun;24(6):1380-5. doi: 10.1111/j.1420-9101.2011.02275.x.
Brain development shows high plasticity in response to environmental heterogeneity. However, it is unknown how environmental variation during development may affect brain architecture across life history switch points in species with complex life cycles. Previously, we showed that predation and competition affect brain development in common frog (Rana temporaria) tadpoles. Here, we studied whether larval environment had carry-over effects in brains of metamorphs. Tadpoles grown at high density had large optic tecta at metamorphosis, whereas tadpoles grown under predation risk had small diencephala. We found that larval density had a carry-over effect on froglet optic tectum size, whereas the effect of larval predation risk had vanished by metamorphosis. We discuss the possibility that the observed changes may be adaptive, reflecting the needs of an organism in given environmental and developmental contexts.
大脑发育在应对环境异质性时表现出高度的可塑性。然而，目前尚不清楚在具有复杂生命周期的物种的生命史转换点期间，发育过程中的环境变化如何影响大脑结构。此前，我们表明捕食和竞争会影响普通青蛙（Rana temporaria）蝌蚪的大脑发育。在这里，我们研究了幼虫环境是否会对变态后的个体大脑产生延续效应。在高密度下生长的蝌蚪在变态时有较大的视顶盖，而在面临捕食风险下生长的蝌蚪的脑下垂体较小。我们发现，幼虫密度对视丘大小有延续效应，而幼虫捕食风险的影响在变态时已经消失。我们讨论了观察到的变化可能是适应性的，反映了生物体在特定环境和发育背景下的需求。
