06:56
Paths of Pollution: PCBs and the Great Lakes
As industries began to proliferate around the Great Lakes and its tributaries, contamination also began to accumulate in its waters. PCBs, which do not biodegrade, were routinely discharged into the environment before scientific evidence revealed th...
02:12
Paths of Pollution: Great Lakes: The Problem of Cross-Contamination
Areas that are not directly contaminated by industrial pollutants can be cross-contaminated through the migration of fish and water fowl. The Wold River is such a spot.
01:17
Food for Thought: Transfer of Energy, The
While the term "food chain" is still used by some to describe the transfer of energy between organisms, others contend that the complex nature of this process is better described by the word "web," rather than "chain."