The Cobra Effect is Real... even if the cobras weren't

The video discusses unintended consequences of bounty systems. In India, a bounty on cobras led to breeding more snakes. In Vietnam, a bounty on rat tails resulted in tailless rats. In Java, a reward for skull fragments caused locals to smash complete skulls. These examples illustrate how incentives can backfire.

What was the outcome of the French bounty for rat tails in Vietnam?

What did the German paleontologist in Java encourage locals to do, and what was the result?