The Last Word On Nothing

This post originally ran in April of 2016. Every dusk, still, the crows fly singly or in groups over my house in Portland, bound west across the Willamette River for their unknown roosting spot. One of these nights I’m going to grab my bike and head after them. Then you’ll probably read about it here. In the meantime, here’s that murdermuration again, along with some of my favorite bird art.

Corvids are a wonderful genre of beast.

I was reminded of this fact not long ago when, biking back home across southeast Portland from the waterfront, a veritable river of crows began streaming overhead. Thousands of them blurred and bobbed and circled each other in a stuttering current from east to west. This current eddied over warehouses. Spilled over parking lots. Formed a recirculation hole over the freeway, then fanned into a delta and out of sight beyond the skyscrapers of downtown. Corvid biologist John Marzluff later told me that the crows were likely heading for a communal roost to settle for the night. There’s one in his home city of Seattle that’s 15,000 strong.

Besides coalescing into this sort of breathtaking “murdermuration,” as I’ve decided to call it, crows recognize their dead, understand analogies, and one species, the New Caledonian crow, even makes its own tools.

Yet while crows and ravens get most of the attention, smaller members of the corvid family like jays and nutcrackers are out in the world busily building and rebuilding forests. Not on purpose, of course, but through a behavior charmingly called “scatter hoarding,” which basically involves stashing seeds around in various places for later devourment. (The same phrase could easily describe the way I distribute books throughout my house.)

In February, a group of scientists led by Mario Pesendorfer of University of Nebraska, Lincoln published a sweeping review of the available research that elegantly lays out just how important and pervasive this relationship is: Many broadleaf trees, including hickories, oaks, chestnuts and beeches, rely entirely on scatter-hoarders to spread their large, heavy seeds, while 20 percent of pine species do. The authors suggest that this reliance may help some of these species better weather forest fragmentation caused by human activities like farming, or shift their range in the face of climate change.

Unable to walk or fly themselves, in other words, these trees borrow the wings of birds. More…

Christie kicked off the week by reduxing a post about the time she lost her phone, and found her brain: The impossibility of sharing with the rest of the world whatever moment I was experiencing here and now was a powerful reminder of how much more I take in when I’m not relying on technology to document what I’m seeing.

Guest Lauren Gravitz commiserates with a pair of woodpeckers at her feeders as they try to keep up with their fledgling’s demands for food: I don’t get to witness such clean, clear progress from the vantage point of my own parenting. The hours of begging are exhausting and, most days, result in little more than frustration. 

Emma chronicles plant behavior research–and finds we shouldn’t underestimate our more-rooted companions: Apart from making the oxygen you breathe and providing the basis for the food web upon which you depend, plants may also be basically as smart as you are—just less hasty.

Sarah studied birds this summer on one of the Pribilof Islands, and bears witness to their decline: It was an enviable gig, staring at the Bering Sea every day. The birds were as thick in the air as mosquitoes, or pasted to the cliffs in a great, chattering mass…But the beauty couldn’t mask another thing the three of us watched slowly unfold: Most of the birds were failing.

I reduxed a post about rainbow eucalyptus trees after finding a newly-beloved (but less colorful) tree had been axed: Later that night that night I was doing what those centuries-old Californians did—dreaming of planting my own neighborhood eucalyptus invasion. Rainbow trees, they could do anything! If people saw these trees, wars would stop, credit card companies would stop charging interest, and we’d all break out into song, right?

Have a good weekend!

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Red kittiwake drawing by Sarah Gilman.

 

Can plants behave? Can they weigh risk against reward? Do they have personalities? A new study suggests they can and do—and that we’ve missed their complex behavior in part because they live life at such a different pace.

Mimosa pudica, or “sensitive plant” is a frilly plant in the pea family with a wonderful talent—when touched, its leaflets fold up, demurely and rather sedately (but fast as all-get-out by plant standards) as if to say “I’m too proud and reserved to be eaten.”

The plant, despite its rather refined air, has weedy proclivities and has naturalized across the tropics, so its party trick must be adaptive. But the “touch-me-not”, as it is also called, has to do a bit of cost benefit analysis when deploying its rapid-fire defensive mode. You see, although closing the leaves reduces the area available to munching herbivores like insects, it also reduces photosynthesis by about 40%. Much like an animal that cannot forage or hunt for food while it is hiding, the plant can’t eat while it is tucked away. So how does it decide how long to keep those lovely bipinnate leaves hidden? Continue reading →