Built-in Wing Dampening - _TNY_0383
This little orange and yellow beauty next to my mother-in-law's garden pond is a female black darter (Sympetrum danae), known as the black meadowhawk in North America.
If you look closer on the wings you can see one cell per wing which is darker. These are called pterostigmata (singular form: pterostigma) and are a nice little piece of evolution.
These are heavier that the rest of the wings and without them, the dragonfly wouldn't be able to glide as efficiently as they reduce the amount of flutter the wing generates. Flutter is a kind of self-exciting vibrations and the pterostigmata allow the wings to move something like 10-20 percent faster.
Built-in Wing Dampening - _TNY_0383
This little orange and yellow beauty next to my mother-in-law's garden pond is a female black darter (Sympetrum danae), known as the black meadowhawk in North America.
If you look closer on the wings you can see one cell per wing which is darker. These are called pterostigmata (singular form: pterostigma) and are a nice little piece of evolution.
These are heavier that the rest of the wings and without them, the dragonfly wouldn't be able to glide as efficiently as they reduce the amount of flutter the wing generates. Flutter is a kind of self-exciting vibrations and the pterostigmata allow the wings to move something like 10-20 percent faster.