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The American Hospital     Few institutions have undergone as radical a transformation as the hospital has in its modern history. It is perhaps distinctive among social i...

The Azolla Event     During the early Eocene period, about 56 million years ago, Earth's atmosphere had high levels of carbon dioxide(CO2) which warmed the planet. But a...

The Deforestation of England Today's typical English countryside of rolling green fields and few trees did not evolve naturally. England was originally wooded. Forests of oak and ...

Reconstructing the Spread of the Grain Weevil Perhaps the most common, most widespread, and arguably most destructive pest of stored grain in history is the grain weevil Sitophilu...

Dutch Art and the Middle Class     Throughout history,the wealthy have been the most avid art collectors. Indeed, the money necessary to commission leading artists to ...

Lenape Horticulture       Older scholarship on Native Americans assumed that, at the time of their first contact with Europeans, Native Americans in the northeaste...

  Sensory Ecology     Some of the most important sensory information animals have to process comes from other animals. Interactions between predators and prey, pare...

Early Astronomy As surviving records and artifacts make abundantly clear, many early cultures took a keen interest in the changing nighttime sky. But unlike today, the major drivin...

Life in an Estuary An estuary is the wide part of a river where it flows into the sea. It is affected by both marine influences(tides, waves, and the influx of saline water) and ri...