Small bird, big curve

Originally published 8 April 1996

“God loves a curved uni­verse,” said design­er and engi­neer Buck­min­ster Fuller.

Let me tell you about one of the big curves, a curve that embraces the plan­et and clos­es upon itself.

For details of the sto­ry I am indebt­ed to Bri­an Har­ring­ton’s recent­ly pub­lished The Flight of the Red Knot. Har­ring­ton is an ornithol­o­gist on the staff of the Manomet Obser­va­to­ry for Con­ser­va­tion Sci­ences in Manomet. The red knot is a small shore bird that vis­its the Mass­a­chu­setts shore in late summer.

Each year, the red knot trav­els more than 18,000 miles, from the south­ern tip of South Amer­i­ca to the arc­tic islands of north­ern Cana­da and back again.

From Octo­ber to Feb­ru­ary, the red knot lives and feeds on the beach­es and mud flats of Tier­ra del Fuego, the south­ern­most land on Earth, exclud­ing Antarc­ti­ca. In the aus­tral sum­mer, the bird replaces its pri­ma­ry feath­ers in a long molt, which ensures that its flight equip­ment is in top con­di­tion when, in Feb­ru­ary, it lifts off in flocks of hun­dreds or thou­sands for the jour­ney north.

Up the coast of Argenti­na, across the hump of Brazil, out across the track­less Atlantic, the lit­tle birds go, stop­ping occa­sion­al­ly along the way to fuel up with fat. The longest over­wa­ter leg of the jour­ney requires non-stop fly­ing for a week.

In mid-May they arrive on tar­get at their feed­ing grounds on the marshy shore of Delaware Bay, just as horse­shoe crabs are lay­ing their eggs by the mil­lions. After a few weeks of gorg­ing them­selves — a sin­gle red knot might devour 135,000 horse­shoe crab eggs — they take to the air again for a non-stop flight to islands of the Cana­di­an arch­i­pel­ago north of Hud­son Bay.

Here, in the north­ern sum­mer, they mate and breed, each female lay­ing four speck­led eggs which she and her mate incu­bate in turns. Baby knots, like oth­er young shore­birds, are up and about as soon as they hatch, grow­ing rapid­ly and replac­ing natal down with juve­nile feath­ers in prepa­ra­tion for flight.

By mid-July, the female adult birds head south again, and male adults fol­low a few weeks lat­er. The juve­niles fend for them­selves until late August, when they too take to the air for the 9,000-mile jour­ney to Tier­ra del Fuego.

These young birds in their thou­sands, with­out adult guides, find their way along an ancient migra­tion route, down across New Eng­land’s Atlantic beach­es, across the Atlantic to Guyana and Suri­nam, then down along the east coast of South Amer­i­ca, arriv­ing with pre­ci­sion at just those places along the way where they are sure to find food.

A map of their jour­ney and the knowl­edge they need for nav­i­ga­tion is part of their genet­ic inher­i­tance. When you con­sid­er that they start­ed their lives, like the rest of us, as a sin­gle infor­ma­tion-packed fer­til­ized cell, their migra­to­ry feat stands as one of the great won­ders of the nat­ur­al world. That sin­gle cell con­tains the bio­log­i­cal equiv­a­lent of a set of charts, a com­pass, a sex­tant, and maybe even some­thing equiv­a­lent to a satel­lite nav­i­ga­tion system.

How do they do it? No one knows. The sun, the stars, Earth­’s mag­net­ic field, angles of polar­ized light: All may pro­vide cues to keep the birds on course.

Har­ring­ton writes about watch­ing flocks of red knots take off from the shore of Delaware Bay for their flight to Cana­da, veer­ing first to the left, then to the right, in ever nar­row­ing devi­a­tions, as if they were some­how cal­i­brat­ing their nav­i­ga­tion­al equip­ment before set­ting a final course.

I won­der if their flock­ing and con­sid­er­able skills of fly­ing in for­ma­tion might not be relat­ed to their nav­i­ga­tion­al prowess. Sure­ly, it is not just one bird that guides the rest. Every bird must exer­cise its nav­i­ga­tion­al instinct. The flock must inte­grate the course set­tings of all the birds, strik­ing an aver­age, in a spec­tac­u­lar feat of par­al­lel infor­ma­tion processing.

If this guess is cor­rect, the red knot’s flight might be a case where evo­lu­tion has favored the group, as opposed to the individual.

The deep­est ques­tion of all is how the birds ever got start­ed on this ancient annu­al cir­cuit, this end­less sum­mer of eat­ing, molt­ing, mat­ing, and breed­ing that so bril­liant­ly uti­lizes the plan­et’s far-flung resources.

The answer to that ques­tion is lost in the deeps of time. But think of the many ele­ments of cre­ation that are tied togeth­er in the red knot’s flight: deep time, geo­log­i­cal his­to­ry, cli­mate, the motion of the stars, sun and moon, the Earth­’s mag­net­ic field, light, tem­per­a­ture, wind, water, mus­sels, clams, horse­shoe crabs, sex, ener­gy, DNA, humans who churn up beach­es with recre­ation­al vehi­cles, and humans who trav­el thou­sands of miles to band and observe birds — and God knows what else, all bound up in one lit­tle flier’s spec­tac­u­lar cir­cu­lar flight.

The les­son of the red knot is that the uni­verse is one. God loves a curve because the curve is the line that turns back upon itself, bind­ing, rein­forc­ing, mak­ing whole.