I found myself explaining that being a tree is sort of the plant equivalent of being a crab. There’s a ton of variety of trees out there, and they all look, well, like trees. The thing about that is, they aren’t really closely related at all. An apple tree is more closely related to a dandelion than it is to a Ponderosa Pine. Completely different lineage.
This is an example of what evolutionary biologists tend to call Convergent Evolution. What basically happens is that there is one really good way to be something, and so lots of distantly related groups end up looking very similar. In animals, this looks like crabs.
It’s so common there’s actually a specialized word for it; carcinization. It’s definitely an oversimplification to say that everything evolves into crabs, but crabs have evolved five different times, which definitely suggests that there is something good about being a crab.
Of course, trees have evolved independently way more times than crabs have, so arguably being a tree might be better than being a crab.
So- there’s your new word, and biology trivia, all in one.
Trego's Mountain Ear 