Choosing your mate is an important decision. If you are a species that cares for your offspring, you and your mate need to be able to coordinate your care, and you must be able to rely on your mate to pull their weight. (Watch the albatross cam to see how the mated albatrosses depend on each other—one stays back with the chick while the other flies off to get food. If the food-getter never came back, or the chick-minder wandered off, the chick would die.) More fundamentally, whether or not you care for your offspring, you and your mate must be able to have biologically healthy offspring together.
Animals do not always get this right. The recently-in-the-news stories of Thomas the goose, who bonded with a black swan and spent his days helping that swan and his mate raise their cygnets, and Nigel the gannet, who was devoted to a concrete gannet dummy, are good examples of the errors an animal heart can make. From an evolutionary perspective, these are bad decisions: they prevent the lovestruck individual from passing on their genes to future generations. (All reports suggest that Thomas and Nigel appeared happy, so from an individual perspective, the mistake may not be so bad.)
But sometimes—very, very rarely—an error in mate choice, instead of being an evolutionary dead end, is the beginning of an entirely new lineage.
When we catch a bird at the banding station, we look it over—and the bird eyeballs us right back.
The pale eyes mean this Bushtit is female.
The sun rising behind the mist nets at the banding station.
‘Tis the season for year-end “Best of” lists, so I thought I’d do something of the sort for my 2017 banding station birds. Except it turns out that we had too many cool birds this year to fit in one blog post, so I’ll be doing a series of banding station highlights posts. First up: the small and fuzzy.
Female Golden-crowned Kinglet
It’s traditional to be thankful around this time of year in the United States, but that isn’t easy this year. Science and the environment are under serious attack, and it’s not clear that the situation will improve anytime soon. We are losing time we won’t get back: students who might have been our next scientific leaders won’t be able to afford education and will turn their careers elsewhere; species and habitats will be irretrievably lost.
It’s too easy to get buried in these discouragements, exhausted and dispirited, and turn away rather than watch more damage done. But we can’t let the things we love become things we don’t want to think about. The things we love are in peril: if we are to save them, we need to think about the love as well as the peril.
Let’s be thankful for the things we might lose. Let’s remember why we treasure them.
I am thankful for all the other lives in this world: all the alien minds, the perspectives built of senses I barely have (smell) or lack entirely (echolocation; detection of magnetic fields), the goals both remote (time to fly from Alaska to New Zealand!) and familiar (must protect my family!), the pleasures that are at once recognizable and strange (the contentment of a mother oppossum with all her babies in her pouch; the joy of a dust-bathing sparrow). I am thankful for how these other lives expand my mind and also for how they have nothing to do with me. I am thankful for the opportunity to glimpse some of them.
One of those other lives: a one-legged (but healthy) Black Phoebe.
Science requires careful planning, foresight, and scrupulous attention to detail. Everything must be controlled so that the variables of interest can be examined. One mistake could bring everything down. Only with years of training can someone hope to add to our body of knowledge.
But if you take all of that too seriously, you’ll spend all of your time planning and theorizing rather than looking—and the most important part of science happens when people just start looking.
Peder V. Thellesen is a dairy farmer in Denmark. He has no formal scientific training. Evidently he loves starlings: he started banding them and observing their nests in 1971 and continued to do so every year, in nestboxes on his own farm and on his neighbors’ farms.
It’s easy to see how you might fall for that gorgeous plumage. Photo by Phil McIver, reproduced from flickr under a Creative Commons license.
It’s the time of year when migrants come through the banding station on their way from their breeding grounds in the north to their wintering grounds in the south. We see a greater variety of species now—not just those who like to breed here, but everyone who thinks our patch of forest looks like a good place to stop for a snack. It isn’t just that these are different species, though: these birds have a different feel to them. These are travelers on a genuinely long and perilous journey. We banders are, I hope, just a blip in any bird’s day—a frightening moment to be shaken off by mid-afternoon—but the days we interrupt for these migrating birds are epic days.
This is physically manifested, on the birds, as fat.
You would think an embryo in an egg could relax. They can’t eat, or go anywhere; what can the world ask of them, besides that they grow? A decade ago it would have seemed ridiculous to talk about “embryo behavior.” Now, though, we know that even embryos have things to do.
There’s more going on in there than you think. Photo by Chris Setter on flickr, used via a Creative Commons license.
Every scientist has a few favorite science stories: those papers or sets of papers that we read early in our careers and then reread often, that we think of when we imagine our own ideal research program. One of mine—not exactly a hidden gem, as it’s in all the textbooks now, and is the subject of a very good general-audience book, The Beak of the Finch—is the Grants’ work on Galápagos finches. Peter and Rosemary Grant have spent decades documenting how bill size and shape in these finches fluctuates as rainy years and droughts change the food available on their small island. It’s as complete a picture of evolution in real time as anyone has ever drawn, and a powerful argument for predictable rules (like “bills must be the right size to open the seeds that are available”) leading to unpredictable outcomes in the complexity of a natural system. It’s beautiful.
I wanted to see if I could see similar patterns in the juncos. Like the finches, juncos are primarily seed-eaters. Unlike the finches, the juncos are not neatly contained on a small island; and unlike the Grants, I did not have 30 years to study them. Fortunately, I work in a museum, which is basically a biological time machine. Want to know what junco bills looked like in 1915? No problem!
Thus my time communing with the long-dead feathered denizens of the specimen drawers. Where the Grants had had to live through the decades of data they acquired, I took a shortcut.
Like all shortcuts, however, there were some downsides. I did not get to live in the Galápagos. Also, I was very limited in which juncos I could measure: I might be interested in juncos from a certain mountain range, but if a junco from that range hadn’t been stuffed and placed in a drawer 70 years ago, I was out of luck.
Every park has at least one weird duck. It’s the wrong colors—all white, or patchy white; its bill bright storybook orange or its face weirdly red and lumpy. Next to the other ducks it looks oversized and bulky, like a linebacker in a crowd of quarterbacks.
How new species form, and what determines whether they last, is one of the major topics in evolutionary biology; and much of this topic is embodied by that one weird duck.
Male Common Yellowthroat, a frequent visitor at the banding station.
Unusually heavy rains have put much of the banding station underwater for the past three months. One side effect of this is that, on the days when the area is sufficiently dried out for us to squelch out in our rubber boots and band birds, the mud shows the tracks of everyone else who has been out there before us.
Usually the denizens of the banding station of whom I am aware are the birds we catch in the nets and band. These tend to be small- to medium-sized songbirds. The mud reveals an entirely different set of creatures living in the area.
Raccoon hand prints near a human bootprint.