After breeding, if you’re a bird, comes molting. Time to discard those old, worn, raggedy flight feathers and start with some fresh ones for the long haul of the fall molt, or replace sparse downy feathers with good warm ones for the cold of winter. This means that around now—from mid-July to September—you may see a lot of birds who aren’t looking their best.
Something is not quite right here. What is it?
I was supposed to be done with field work after summer 2015, but you know how it is. The birds call. You realize that a few more blood samples would put the patterns you’re seeing in context in an illuminating way. You miss those feathery little dudes.
The small amount of field work I did this year took place much earlier than my usual field work because I was sampling juncos at a much lower elevation. Down here, the juncos are breeding in mid-March. Up at my usual sites, they wait until late May. That early start happened to be convenient for me, since I needed to analyze any data I got in time to file my dissertation in mid-May.
We were searching for junco nests when I heard the unmistakable tic-tic-tic of junco alarm chipping. We followed the sound a ways and found a pair of juncos perched on a low branch, alarm chipping for all they were worth. Strange of the juncos to be alarm chipping at us when we were so far away, before, I thought. I wouldn’t have thought they’d see us as a threat from that far away. Odd birds. Directly below the branch with the agitated juncos was a small shrub. “The nest will be in there,” I predicted, showing off for my new field assistants.
And just as I said that, I saw the snake.
I held off getting a smartphone for a long time. I frustrated friends who tried to text my ancient flip phone internet links and baffled people by actually getting lost and having to phone for directions. (Who gets lost these days? Everyone has Google Maps in their back pocket now.)
But I’m going to two conferences in unfamiliar places this summer, and I don’t particularly want to get lost in Alaska or Brazil. So I got a smartphone. And now I have a camera in my back pocket all the time.
Not surprisingly, in my hands this has mostly yielded pictures of birds.
Not too long ago, the generally-accepted answer to this question would have been: “Not really—a few birds do, but most don’t.” This was largely based on the observation that most birds have very small olfactory bulbs in their brain relative to their overall brain size. As we observe bird behavior, however, we are are increasingly realizing that most birds can and do use smell regularly, often for very important things.
Let’s begin with the birds that have been known for a long time to use smell. Kiwi birds are unique in having their nostrils on the end of their bills, rather than close to the base of the bill like all other birds. Kiwis stick that long bill into the soil and use their nostrils to sniff for insects and worms.
It makes a lot of sense that kiwis have a good sense of smell, even if you think that birds in general don’t, because kiwis seem to have evolved to be the avian version of a small fuzzy mammal. Kiwis evolved on the islands of New Zealand, where the only mammals were bats. The small-brown-fuzzy-nocturnal-snuffling-in-the-dirt-for-worms niche was open for the taking, and kiwis—flightless, nocturnal, and covered in long thin feathers that are highly reminiscent of hair—took it. A good sense of smell goes with that niche.
I’ve been neglecting my blog-writing duties lately, preoccupied with the annual Big Grant Proposal Deadline. My grant proposal is on sexual selection in juncos. What part of juncos is sexually selected, you ask? Why, that flashy tail, of course! They’re practically peacocks!
I’ve also been TAing a class on animal behavior, so while I don’t have many extra words to spare right now—I need them all for that grant proposal—I do have a wealth of animal videos that have been brought to my attention by my fellow animal behavior fans. Please accept some videos in lieu of words.
Here is a video of a bird even drabber than a junco who attracts females with his sexually selected aesthetic tastes in things like flowers, shiny beetles, and slightly… er… less attractive items as well: the Vogelkop Bowerbird.
And here are some flies that—well, you should just watch it to believe it. It starts with them gulping air bubbles into their heads, and that’s not even the weird part.
Why are they like that? Sexual selection! Females in this species prefer their males as hammerheaded as possible.
Hey, why not?