In the year 2400 BC, a long time ago, something strange happened with the weather on Earth. We call it a "climate anomaly". Climate means the average weather in a place over many years, so this anomaly means the weather was different than what was expected.
It was like when you expect it to be sunny in the summer and suddenly it starts raining a lot every day. That's what happened with the weather 4,400 years ago. Instead of being hot and dry in some places, it became wet and cold. And in other places that were supposed to be wet, it became very dry.
This happened for a few hundred years, which is a very long time. It affected the plants and animals, and the people who lived back then. They had to adapt to the new climate and change the way they lived. Some plants and animals died out or moved to new places where it was more suitable for them.
Scientists study this climate anomaly by looking at things like rocks, tree rings, and ice cores from the time period to try to understand what happened. They are still learning more about it today!