Red-legged Seriema
How do birds move their feathers?
7
Tag Archives: communication
What bird colors can tell you
Birds need to know a lot about each other. They need to know things like who will be the best parent; who will pass on the best genes; who could defeat them in a fight; and which offspring is worth investing in the most. One of the ways that birds can perceive such information about each other is by observing each other’s color signals—and the more researchers study these, the more it becomes clear that birds can tell a lot from color alone.
Let’s make up a bird species – the Superb Junco. This imaginary species has a black hood and pink bill like the Oregon Junco, but its body and tail are iridescent blue-violet. Here is an illustration of three individuals of this species:
These individuals are clearly different: A has a paler head, B has a paler bill and is less brightly shiny, and C is brightly colored in all aspects. But what does that tell us?
Featured paper: cuttlefish are lying cheaters
Although the cuttlefish may be best known for making those flat cuttlefish bones that your pet bird nibbles to get calcium, this paper shows that it should be known for being a lying cheater.
That was uncalled for.
Photo by Tom Olliver
Cuttlefish, like their relatives the squids and the octopuses, are masters of visual communication. They can change their appearance almost instantaneously (video here), and they use color and pattern to say things like “Back off, I’m angry!” and “Pretty lady, I would like to do some romance with you now,” and “Please don’t do romance with me, I am male.”
Badges of status, or, keeping House Sparrows honest
In many bird species, the males have to acquire and defend a good territory – filled with great food or great places to put a nest – in order to have a prayer of attracting a mate. There’s even evidence that some females pay more attention to the quality of the male’s territory than to the quality of the male, so having a good territory is a big deal.
In these species, males fight a lot. They fight to get territories and then they fight to keep them. It’s a bit like a football game: you have to run fast and smash into people in order to get the ball, and then continue running fast and smashing into people (and withstanding them smashing into you) in order to hang onto it.
Male House Sparrows fighting.
Photo by Jessica Lucia
Photo by Jessica Lucia
All that fighting takes a lot of time and energy, not to mention risk of injury. So the birds (and many other resource-defending animals) have found a less-dangerous shortcut: instead of fighting, they wear “badges of status,” color markings on their body that stand for how tough they are. Birds with less-tough badges don’t bother challenging the tougher birds, and everyone has to fight less. Sounds great, right? It’s the equivalent of a football player wearing a jersey that says “I’m Tougher Than You,” and the other football players just leaving him alone. So much less violent!
… but it doesn’t seem like it should work, does it? If it did, then anybody could put on a jersey that says “I’m Tougher Than Everybody” and win the Superbowl. What stops the birds from lying?
What the chickadees are saying behind your back
Black-capped Chickadees may be the easiest birds to identify by ear. Chick-a-dee-dee-dee, they sing, telling you exactly who they are. (I’ve heard that towhees do this too, but the towhees I’ve heard always seem to be saying twee or taree, from which I would not be able to get “towhee” unassisted.)
Don’t you know who I am? I’m Chick-a-dee-dee!
[A Mountain Chickadee, not a black-cap, but I don’t have any photos of black-caps.]
Tough Little Birds 