Pettigrew J D
Science. 1986 Mar 14;231(4743):1304-6. doi: 10.1126/science.3945827.
The pattern of connections between the retina and midbrain has been determined with electrophysiological and neuroanatomical methods in bats representing the two major subdivisions of the Chiroptera. Megachiropteran fruit bats (megabats), Pteropus spp., were found to have an advanced retinotectal pathway with a vertical hemidecussation of the kind previously found only in primates. In contrast, the microchiropteran bat Macroderma gigas has the "ancestral" or symplesiomorphous pattern of retinotectal connections so far found in all vertebrates except primates. In addition to linking primates and megachiropteran bats, these findings suggest that flight may have evolved twice among the mammals.
通过电生理和神经解剖学方法，已确定了代表翼手目两个主要亚目的蝙蝠视网膜与中脑之间的连接模式。大蝙蝠亚目的果蝠（大型蝙蝠），如狐蝠属，被发现具有先进的视网膜顶盖通路，其垂直半交叉类型此前仅在灵长类动物中发现。相比之下，小蝙蝠亚目的蝙蝠巨耳蝠具有迄今为止在除灵长类动物之外的所有脊椎动物中发现的“原始”或同形特征的视网膜顶盖连接模式。除了将灵长类动物和大蝙蝠亚目蝙蝠联系起来之外，这些发现还表明飞行可能在哺乳动物中独立进化了两次。
