Difficulty: Summiteer (Level 3)
Rats are found everywhere around the world, except Antarctica, and are often seen as a sign of poverty and disease. A recent study shows that as the climate warms, rat populations are also increasing.
This growing rat population is a problem for city officials, as rats can cause damage to infrastructure and spread diseases.
Some cities spend around US$500 million (around HK$3.9 trillion) every year controlling rats. In New York, Mayor Eric Adams has launched a “war on rats,” appointed a special official for rat control and even held the city’s first National Urban Rat Summit.
However, reliable long-term data on rat populations is lacking. Researcher Kaylee Byers noted that while public complaint data about rats is useful, it can be inconsistent.
Answer: because of climate change
