Nonadaptive radiation

So, you know how animals can change over time to better suit their environment? Like how a polar bear has white fur to blend in with the snow, or how a giraffe has a long neck to reach tall trees for food? This is called adaptation.

But sometimes, animals don't change at all even though their environment might change a lot. This is called nonadaptive radiation.

Let's say there's a population of birds living in a forest. Over time, some of the birds might get bigger or smaller, or develop longer or shorter beaks, to better survive in the forest. But there might also be a group of birds that stays the same, even if the forest gets thicker or thinner or different in other ways. This group of birds is experiencing nonadaptive radiation.

It's like if you were playing a game with your friends, and some of them changed the way they played to make it easier, but some of them kept playing the same way even though it was harder. Nonadaptive radiation is when some animals don't change to make their lives easier, even though they could.