The human digestive tract is like the Amtrak line from Seattle to Los Angeles: transit time is about thirty hours, and the scenery on the last leg is pretty monotonous.
The human digestive system has a complex and lengthy journey, akin to a long train ride where the trip takes about thirty hours to complete. Just like the scenery along the Amtrak route between Seattle and Los Angeles can become quite dull, the final stages of digestion can lack excitement. This comparison emphasizes the relatively uneventful nature of the digestive process.
In her book "Gulp: Adventures on the Alimentary Canal," Mary...