> New research suggests that bird ancestors shrank fast, indicating that the diminutive size was an important and advantageous trait, quite possibly an essentia

> New research suggests that bird ancestors shrank fast, indicating that the diminutive size was an important and advantageous trait, quite possibly an essential component in bird evolution. This is making the common mistake regarding evolution. Evolution doesn't select for advantageous things, but against disadvantageous things. It's not survival of the fittest, but death of the inadequate. It seems nitpicky, but it's very important for diversity. If getting larger or smaller doesn't drastically hinder your survivability, then one ends up with a large range of sizes.