难句类型:复杂修饰、插入语、倒装
More probable is bird transport,either externally,by accidental attachment of the seeds to feathers,or internally,by the swallowing of fruit and subsequent excretion of the seeds.
更有可能的是鸟类运输:或者是通过外部途径,即由于种籽偶然粘附在羽毛上;或者是通过内部方式,即由于鸟类吞食果子并随后将种籽排泄出来。
解释:句首有一个倒装,正常语序是bird transport is more probable。后面的句子中由于插入部分的频繁出现使句子显得十分凌乱。