Failures to stop a deadly threat to cars from 18-wheelers

Main Topic: The podcast episode discusses three main topics:

1. The failure of government regulators to protect drivers from deadly underride crashes involving commercial trucks.
2. A new expedition to measure the length of the Amazon River, which is disputed to be the longest river in the world.
3. Scientists using an unusual approach to save coral reefs by broadcasting underwater sounds to attract fish.

Key Points:

1. Underride crashes occur when cars collide with commercial trucks, resulting in devastating injuries and often fatalities. The federal government has failed to track these crashes effectively, and regulators have deferred to the trucking industry's lobbyists, who argue that safety measures would be ineffective and expensive.
2. Crash test data shows that adding stronger bumpers to trucks can significantly improve safety, and the cost is relatively low, around $100.
3. The Amazon River is disputed to be the longest river in the world, with some Brazilian researchers claiming it is longer than the Nile River. An expedition is planned to measure the Amazon River's length from its source to its mouth.
4. Scientists are using an unusual approach to save coral reefs by broadcasting underwater sounds, including fish calls, to attract marine life back to degraded reefs.