ABSTRACT
This chapter expresses that growing human population, production, and exchange in medieval Europe interacted with the communities of plants and animals in Europe's streams and lakes. It describes the ways in which well-known medieval economic developments altered them after identifying natural features of Europe's aquatic ecosystems. The chapter focuses on the lands of medieval Western Christendom from the Mediterranean coasts to Scandinavia. The historical discipline would treat serious issues of politics and the higher literary and artistic activities of the human mind. Environmental historians explore and reconstruct these mutual interactions, bridging Crosby's chasm to identify precise and changing relationships among certain people and particular ecosystems. Natural aquatic ecosystems in Europe result from the physical geography and Pleistocene glaciation of the subcontinent. Europe projects as a peninsula from the larger land mass of Eurasia; ecologists find that a peninsular situation commonly reduces the variety of all resident life-forms.
