I wrote about birds and mirrors a while ago, and not much has changed scientifically since then. Most bird species tested have interpreted their own reflections as other individuals, responding either with aggression or courtship. Female pigeons who view their own reflections ovulate, apparently interpreting their reflections as suitable mates. Among birds, only magpies, so far, have been demonstrated to understand that the mirror reflects their own image, although pigeons can be trained to use spatial information from mirrors correctly in the real world.
So why bring this up again? Recently I saw a Yellow-rumped Warbler interacting with its reflection in a car side mirror, and took a video with my phone. Here it is (apologies for the lack of zoom):
At the time I took the video, I didn’t think much of it beyond general amusement. But rewatching it, I began to have some questions.
I’m teaching an Animal Behavior course this semester. The lectures are 80 minutes long and exactly during the sleepiest time of the afternoon; I enjoy the challenge of getting a reaction from the students under these circumstances. Videos of baby animals in peril always get attention (some good ones: marine iguana, barnacle goose, water buffalo), but they’re so reliable it almost feels like cheating.
My students have actually broken into applause during lecture three times so far. One of these will not be discussed in detail (it involved the recitation of poetry), but the other two were in response to two quite different animal accomplishments, which I thought I would share.
It’s been a rough few days. If you find birds and flat, open landscapes calming, as I do, here is a video.
Photo by Patrick Emerson*
The full moon is pregnant with foreboding interpretations, from the legendary werewolves who are supposed to transform under its malevolently shining face to a recent article about November’s upcoming full “supermoon” that faux-reassures, “despite all the rumors… there is no evidence linking supermoons to natural disasters.”
If you look at a full moon and shiver, you aren’t alone—but you are a bit of a mystery. In humanity’s past, the full moon should have been the safest time of the month, since our nocturnal predators tend to attack most on dark nights. The new moon should be spooky, as your hindbrain—unaware that you no longer live on the African savannah (unless you do!)—looks out for predators slinking in the shadows. This is presumably why the fear of darkness is such a common and instinctual one. But the full moon is bright: it should be comforting.
In the spring of 2015, a male House Wren and his mate built their nest inside a nestbox near a honeysuckle. His mate laid her eggs and dutifully incubated them. Then, one morning— cheep! cheep! High-pitched calls and gaping red mouths cried hungry, daddy! and the male wren was off in a paternal tizzy, collecting bugs and delivering them to his new offspring.
It was, maybe, odd that his new offspring weren’t in the nest that he had built. It was, maybe, odd that other, larger birds were also feeding his babies. It might even have been called odd that his mate was still sitting in their nest, atop whole and silent eggs. But— cheep! No time for that! The chicks were hungry!
What this male House Wren was doing, no doubt to the profound irritation of his mate, was feeding the offspring of a pair of Northern Cardinals who had nested in the honeysuckle near his nestbox.
Don’t worry: this isn’t Lewis Carroll’s maddeningly unanswered riddle “Why is a raven like a writing desk?” (Although, if you’re interested, it turns out that has been answered.) There is an answer to this one—two answers, in fact.
Answer 1: They both make sounds by vibrating strings.
Well, strings, feathers—they’re all the same, right? This Club-winged Manakin produces its courtship song by vibrating its wing feathers: they strike each other about 107 times per second.
We know a little bit about how dinosaurs probably looked: we’re learning that a lot of them had feathers, and even beginning to be able to figure out what patterns might have been on their plumage. But there’s a lot we don’t know; we may never know for sure.
In evolutionary biology, when you don’t know something about an extinct species—what kind of nest it built, or what sounds it made, or how many babies it had—you look at the species that evolved from it. You infer that it probably was similar to at least some of its descendent lineages. For dinosaurs, then, we would look at birds.
I remember, as a kid, thoughtfully coloring my dinosaur coloring books and paper-mache dinosaur scultures in shades of green and brown. I knew about camouflage, and I was sure that this earthy color palette must have been the one favored by these animals. Silly me.