What Birds Are Saying

Sitting on a wood piling at a marina, a motionless Herring Gull stared out over the boats. Humans strolled by on one side of him (?), boats purred by on the other.

High overhead, two other gulls appeared, flying lazily toward the ocean. Without looking up at all as far as I could tell, the Herring Gull squatted slightly, thrust its neck downwards and its head upwards, and let out several very loud, prolonged squawks, then resumed his silence. The other gulls, if they noticed, didn’t show it.

I was surprised that the Herring Gull was unfazed by the people and boats moving close by but reacted loudly to the two others far above. Was he saying “Beat it”? Or “Hey, good lookin'”? Or did the other gulls have nothing to do with his alarm?

Herring Bull (Wikimedia Commons)

Wikimedia Commons

Judging partly from the gull’s hunkered position, I thought at first that I had heard the Herring Gull’s “choking call,” an emphatic defense best rendered as “No, I’m not moving!” But after more googling, I wasn’t so sure. The call could have been the familiar “long call” of gulls, a series of raucous, trumpeted yawks that assert their territory.

But gulls don’t ever really “sing.” Most of the singers among birds, the makers of trilled, often complex melodies, are closer to home. The Robins, Sparrows, Wrens, Cardinals, Mockingbirds, and other backyard birds that perch on branches and at feeders, hop on the ground, and take flight together are among the maestros. With a vocal organ, the syrinx, that divides where the windpipe forks into the lungs, song birds can produce rapid trills and even two notes at the same time.

Debbie Ackerman in The Genius of Birds (2017) describes the difference between calls and songs. Calls “are typically short, simple, succinct, and innate (like a human scream or laughter), uttered by both sexes to make their point.” Perching birds call to “warn of predators and to identify family, friends, and foes. [Males also] sing to defend their territory—to stake it out or fence it in—and to woo a mate” (141).

The Britannica adds this:

Bird song is best considered the vocalization that is used in courtship and breeding, chiefly by the male, to advertise that he is ready to mate, to attract the female and perhaps stimulate her sexually, to keep the pair together, and to inform rival males that he has established a territory from which they will be excluded. The male’s call are also part of a threat display that take the place of actual combat in repelling intruding rivals. (“Songbird”)

I’ve wondered about the connections between the modest size of such birds, their vocal skills, their perching, and their reproductive success. As a a sophisticated instrument for social communication, their songs may have made them fitter for the flying, flocking, and perching life.  I suspect the subtexts of their singing are as untranslatable as the nuances of human song and conversation.

In any event, their combination of size, sociability, and song has flourished: Today the perching birds number more than half of the 200 to 400 billion individual birds worldwide, and their 5,000 species account for more than all other bird species combined. Not bad for feathery successors of the dinosaurs.*

Wren singing (Wikimedia comm)

Wikimedia Commons

I’m reminded that no type of organism alive now, including ours, has come down from its start as a fixed package of parts and abilities. We living things are the history of our changing survival strategies. Gulls, insects, flowers, trees, apes, humans––we are works in progress, ongoing creations. While we are alive, we are only the current versions.

 

###

*Cheery little birds descended from dinosaurs! Ackerman puts her finger on some similarities:

It’s easy to catch the reptilian in birds. You can see it in their beady eyes and quick darting movements; in the pterodactyl-like wings of a rhinoceros hornbill; in a robin holding up his head in frozen alertness to catch a sound, his expressionless face remindful of a lizard’s; or in a great blue heron—the slow heavy wing beat, the snaky finesses of its neck, the hoarse squawks, are all a throwback to dinosaur lagoons. But it baffles the imagination to think that the tiny flashlike chickadee could have arisen from the big beasts of vanished ages. (45)

In addition to sources mentioned, Wikipedia, Quora,  Earbirding, and Cornell University’s All About Birds have been useful sources.

My Million-Year-Old Back Yard

I like knowing the age of living things—not the age of the individual organism but of the lineage, of how long a plant or animal has been different from other lineages. The dates give me a glimpse of a Past that, like a god, generates and then consumes everything.

So here are the ages, youngest first, of the plants and animals in my suburban yard. Dates are approximate by millions or tens of millions of years!

The youngest creature in the yard is our dog, an animal that separated from its wolf-like ancestors about 40,000 years ago.

Next is me and my wife. Our species, Homo sapiens, separated from our Homo ancestors about 200,000 years ago. Before that, our genus, Homo, split off from the genus that chimps belong to about 7 million years ago. All our ancestors in our genus have died off and we are the only member left, a strange isolation. We are probably the only species in the yard in that situation.

The youngest plant is the grass, appearing about 40 million years ago among plants that adapted to a warming climate.

Back yardThe first squirrel fossil dates from 36 mya. Squirrels are part of a huge group of rodents with big, continually growing teeth. The chipmunks are in the same category.

An oak tree dominates the yard. Although trees in general have been around for much longer, the oak was part of the spread of flowering plants, at very roughly 70 million years.

There’s a holly tree. The several hundred species of holly emerged about 80 million years ago.

Other flowering plants and trees come next. Their ancestors began diverging from flowerless plants around 240 mya, they were blooming 160 mya, and they became widespread and then dominant among plants during the 100 million years after that.

Insects originated about 600 million years ago, but the modern insects in the yard—flies, butterflies, wasps, bees, ants— co-evolved along with the flowering plants from 146 to 66 mya.

The birds are thought to have evolved from certain dinosaurs that carried feathers for warmth, about 180 million years ago.

The pine trees and cedars around the house are among the conifers that date back 300 million years when early trees began to live away from the water. Conifers reproduce through exposed seeds (on pine cones) and pollen. Protected seeds, enclosed in nuts and fruits, came later.

Two other back-yard inhabitants go back as far as the conifers: Ferns, not so different 350 million years ago, with their tiny, single-cell spores, another predecessor of the modern seed. And spiders, spinning their silk about 300 million years ago.

I’m realizing, as I finish hunting through Wikipedia for these dates, that my intentions have become a little muddled. The “birth” of these species was more process than event, a long interweaving with their early kin. The age of a rose depends on whether you look at it as a rose or a seed-bearing plant or a land plant.

Still, I savor the majestic history here, the story of life.