Roth R L
Proc Natl Acad Sci U S A. 1979 Aug;76(8):4131-5. doi: 10.1073/pnas.76.8.4131.
In the goldfish, the optic nerve decussation occurs without intermingling of fibers from the two eyes. In two-thirds of juvenile and adult specimens, the left optic nerve is dorsal at the midline. In about 60% of the specimens, the decussation of Mauthner's neuron also has a left-dorsal-to-right (L/R) configuration. Concordance for decussation geometry is greater than 80%, with smaller specimens accounting for a disproportionate number of discordant cases. In embryos and very young larvae, the L/R configuration occurs in slightly less than 50% of optic chiasmata and in slightly more than 50% of Mauthner's cell chiasmata, and there is no significant tendency toward concordance. However, larval specimens that survive 1 month after hatching are markedly skewed toward adult decussation patterns and somewhat skewed toward concordance. These observations, together with results of cannibalization and predation experiments, suggest that the adult population pattern can be achieved through selection pressures against discordant individuals and, perhaps separately, against individuals with right-dorsal-to-left (R/L) chiasmatic configurations. Decussation patterns correlate with embryonic postures, larval orientation preferences, and growth rates after hatching, which may themselves serve as a basis for selection.
在金鱼中，视神经交叉发生时，来自两只眼睛的纤维不会相互交织。在三分之二的幼年和成年标本中，左侧视神经在中线处位于背侧。在大约60%的标本中，莫纳神经元的交叉也呈从左背到右（L/R）的构型。交叉几何结构的一致性大于80%，较小的标本在不一致的病例中占比过高。在胚胎和非常年幼的幼虫中，L/R构型在略少于50%的视交叉和略多于50%的莫纳细胞交叉中出现，且没有明显的一致倾向。然而，孵化后存活1个月的幼虫标本明显偏向成年交叉模式，并且在一定程度上偏向一致性。这些观察结果，连同同类相食和捕食实验的结果表明，成年群体模式可以通过对不一致个体以及或许单独地对具有从右背到左（R/L）交叉构型的个体施加选择压力来实现。交叉模式与胚胎姿势、幼虫定向偏好以及孵化后的生长速率相关，而这些本身可能作为选择的基础。
