The Emperor Penguins
A Canadian who writes of the natural world with scientific accuracy and the pull of humor, N. J. BERRILL, Professor of Zoology at McGill University, is the author of The Living Tide, which was published last year. He is now working on his new book, Journey into Wonder, an account of the voyages and explorations of the great naturalists, which Dodd, Mead will publish this autumn and from which the Atlantic will select three installments.
byN. J. BERRILL
CAPE CROZIER is the eastern extremity of Ross Island in the Antarctic, Crozier is where the western edge of the ice barrier squeezes into the sea, with all the mass and pressure of the greatest ice sheet in the world moving behind it. When Robert Scott sailed the Discovery into the Ross Sea in 1902, he took with him Edward Wilson, the naturalist, and Sir Ernest Shackleton. In 1903 the three of them made the first southern journey over the ice toward the pole, over the length of the Great Ice Barrier to the foot of the Beard more Glacier—nearly a thousand miles there and back.
At Cape Grozier the barrier ice piles itself up against Mount Terror, and, of all places on earth, this is where the Adélie and Emperor penguins breed. Here is the scene, in Wilson’s words: “We were on an old outlying cone of Mount Terror, about thirteen hundred feet above the sea. Below us lay the Emperor penguin rookery on the bay ice, and Ross Sea, completely frozen over, was a plain of firm white ice to the horizon. The sky looked black and threatening, the barometer began to fall, and before long down came the snowflakes on the upper height of Mount Terror. All these warnings were an open book to the Emperor penguins— a long file was moving out from the bay to the open ice, where a pack of some one or two hundred had already collected about two miles out at the edge of a refrozen crack.”Two days later, “the change was immense. Ross Sea was open water for nearly thirty miles; a long line of pack ice was just visible on the horizon from where we stood, some eight or nine hundred feet above the sea. Large sheets of ice were still going out and drifting to the north, and the migration of the Emperors was in full swing. There were again two companies waiting on the ice at the actual water’s edge, with some hundred more tailing out in single file to join them. ‘The birds were waiting far out at the edge of the open water, as far as it was possible for them to walk, on a projecting piece of ice, the very next piece that would break away and drift to the north.”Only those that were yet nursing chicks still huddled under the ice cliffs, sheltering as much as possible from the storm that was driving the ice out of the day. The Emperors went with it, but it was half a year later before the rest of the ice went out and allowed the Discovery to sail home to the north.
Wilson also wrote: “The possibility that we have in the Emperor penguin the nearest approach to a primitive form not only of a penguin but of a bird makes the future working out of its embryology a matter of the greatest importance” ^— a statement that caused no end of trouble, in the sheer physical sense of the word, both to himself and others.
The statement itself is t he product of it s t ime and makes several assumptions. One is that the penguin is a primitive bird and has never known how to fly. which is more than doubtful. Another is that the Emperor is more primitive, as penguins go, than the rest of these inquisitive manikins. And the bird, which brought the trouble, is that if you look closely enough at the early stages of the embryo developing within the egg, you will see in some sort of outline a repetition of its evolutionary past. This idea is a hangover, not from Darwin himself, but from one of his ardent German admirers of the late Victorian age, Professor Ernst Haeckel, a man of immense industry and influence. There was a time, not so long ago, when zoologists everywhere were digging into the life history and embryology of every animal on land or in the sea that they could lay hands upon, with the belief that their individual stories of evolution would drop like ripe plums from a tree. It hasn’t worked out that way, but Wilson was a little too soon to know, and the thought remained.
Copyright 19by The Atlantic Monthly Company, Boston id, Mas. Wrights reserved.
TEN years later Wilson and Scott returned, once more within sight of Mount Terror. This time the pole itself was the goal, and both men were to die on the journey back across the barrier. But before the polar journey started, there was time enough for another — a search for fresh and not too old eggs of the Emperor; eggs that would be laid on the ice, a hundred miles across the barrier, in the dark midwinter of Antarctica. Three set out — Wilson as leader; H. R. Bowers, who also died on the polar journey the following summer; and Cherry Garrard.
They journeyed for live weeks. That may seem not very long, but it depends on how you measure time. By weeks it is little, by days not so much; but measured by minutes of exhausting effort, cold agony, and anxiety, with each dark and bitter and dawnless day a release from the frozen armor of unthawed sleeping bags, the time becomes eternity. They hauled two sledges, each man pulling 250 pounds, over a rough and tricky surface. After a while they could pull but one sledge at a time and had to travel ten miles to make three. At temperatures lower than sixty below zero they went back and forth in the darkness, tracing their own footsteps a few at a time with the aid of a candle, and otherwise steering by the light of Jupiter. In eight hours they accomplished two miles, more or less, with effort so great the mind could not escape, with no respite mentally or physically. Crevicesbecame a nightmare, for they were iced over and any one of them could mean death. Moisture from their bodies froze in their clothes, and there came a time when neither by day nor by night did they thaw, and frostbite found them even in their bags. Only once did they find relief, during a three-day blizzard near the end of the outward journey, when the temperature rose eighty degrees to nine above zero. With that the ice in their clothes and sleeping bags turned to water, from the added heat of their bodies, and they “lay steaming and beautifully liquid” and went to sleep. The cold hell of Dante returned and at times at night each wondered whether the others were yet alive. They did find the eggs of the Emperor, after dark descents with ice axes and ropes — five of them; three of them froze and survived the journey back to England; the other two were crushed in falls.
What did the eggs show? They showed that a penguin is penguin all the way, and that a penguin’s egg is the means by which a penguin gives rise to another penguin. There is no recapitulation of an ancestral past; no light is thrown upon the origin of birds; the penguin fin is a bird w ing from the beginning. Only the manner of feather development is peculiar, and that tells us more of what a penguin is than what a penguin was! Nor is there reason to think the Emperor’s egg could tell us more than the egg of any other penguin; for whether or not the Emperor is more primitive than the rest, all are 99 per cent penguin and tell the same story — which is, a penguin is a bird that cannot fly in the air but uses its wings to fly under water, for that is what it does.
Where does all this leave the penguin? The figure of fun remains; so does the slickest sea bird of them all, a marvelous conversion from flight in unsubstantial air to flight in cold and heavy water—for flight it still is, not underwater paddling or just diving. The padded body is streamlined for speed; the wings are hard and firm for beating against the liquid medium; chest muscles and keel are heavy enough to operate them; feathers are modified to make a dry insulating coat; and sea water is freely swallowed in place of fresh. Below the surface the bird is as fitted to its place as any porpoise, fish, or squid — a lithe, darting, efficient animal with eyes well suited to seeing through water. Only the fast flip to the surface to get air gives it away, and even that, is as brief as the jumping of a fish.
Out of water it is another matter. A penguin cannot fly and has to walk, but legs of streamlined swimming and diving birds are short and they are all a race of waddlers. Good sight under water means poor vision out of it, for corneal curvatures are necessarily different, and penguins and sea lions, for all their prowess as fishermen, are hopelessly shortsighted on the land. Which may be the reason why penguins, when they are on the ice or climbing a more temperate hillside, all follow the footsteps of the leader, trailing their way in long lines — it requires so little sight and thought. Yet this myopia itself tells us something, if only we knew w hat to make of it. Visibility on a smooth iee sheet is no more than three miles even for a man; for short penguins it is less, especially when all distance is a blur. But they travel across extensive ice fields in a direct line to their proper destination; and in the sea, in regions where the water temperatures vary little if at all, they migrate hundreds of miles without chance or equipment for making any celestial sights. If any birds really have a true directional sense, the penguins have it. On these long treks they cannot see their way, smell their way, or feel their way. What is there left? I do not know, and can only wonder.
With most birds the sexes look quite unlike and the birds have no trouble. But not the penguin. Penguins look alike to penguins as well as to men, and a hopeful male penguin never knows what he’s starting. All he can do is to go up to a likely-looking individual, make an offering of a pebble or a feather, and hope for the best. If the offering is ignored, the recipient may be a bored bachelor or an unawakened maiden. If the supplicant gets a good pecking, he has picked upon a thoroughly insulted gentleman. Only when the pebble is graciously received does he know he has met the right kind of girl and the courtship can proceed. Sex is not flaunted.
PENGUINS define the Southern Hemisphere in circles, segments, and spots. Emperors and Adélies fringe the Antarctic shore the world around; Kings, Johnnies, Rock Hoppers, and Macaronis hold the islands throughout the West. Wind Drift; Rings keep to the Scotian Are, the Jackass to Patagonia, Humboldts to Humboldt’s Current, and the Galápagos to its island group. These are not all but they will do. They keep within the cold water but go wherever it goes, and the Galápagos Islands are the northern limit. From south to north, as sea temperatures rise, their size decreases. The Emperor is the greatest, the Galápagos penguin the smallest ; the others and their ranges are in between. It is a matter of weight, heat production, and body surface. At the ice barrier it is hard to stay warm; at the equator one needs to keep cool.
Each kind has its own particular problems of food, home, and happiness, and not all of them are troubled with snow and ice. The Adélie has come in for the most attention, as befits a lady, for she is comic and arresting against the orthodox white Antarctic background. Movies, books, and even radio have carried her fame and foibles to the world at large. Every polar expedition has found her good and inquisitive company. More than most, Adélies are travelers. They spend the winter on the northern edge of the pack ice, and journey more than 500 miles by water to reach the breeding colony at Cape Crozier, and a fairway by foot across the ice. On the ice they travel as fast as a man can run, either walking in short, quick steps or toboganning on their breasts with wings and feet pushing. Ice travel is by daylight only; at night they camp in line till dawn. The ice journey may last two weeks. At the end of the trek the long lines break up, the birds fall on their bellies, and flippers and sternwheeling paddle feet drive all in a noisy free-for-all for the final goal. As the long lines of migrating Adélies come to an end, the Antarctic skuas arrive, the savage marauding gulls that are the greatest enemies of the Adélie’s eggs and young.
On arrival at the nesting grounds the hens stake out the claims, each bird slightly thawing the soil with her breast and scratching a circular scoop. Then she waits in amorous serenity for a mate. Newly arrived cocks begin courting at once, but after the prolonged effort of their recent journey they are apt to go to sleep on their feet at any moment, to take a brief nap a dozen times or more while pressing their suits with the waiting maidens or matriarchs.
If a hen likes the show she may cackle back at the suitor, or she may give him a good pecking, which seems to appease her and merely makes the abused male more supplicant. They then assume the “ecstatic” attitude, cross their beaks, sway from side to side, and cry shrilly. After mating, the cock brings all the round pebbles he can find to make a stone rampart around the scoop, in the middle of which two eggs are laid. If stones can be filched from a neighbor, so much the better. The offended owner then seems to swell with rage, feathers erect and head plumage raised like a topknot, and gives chase. The thief, on the contrary, makes himself look small and sleek and tries to lose himself in the crowd. And when one is recognized before the event, he quickly throws off his keen prowling look and walks nonchalantly by, as though nothing had been farther from his intentions. Family life, once established, is usually tender, faithful, and affectionate, although some couples remain in squabbling bondage. There is a little too much comic caricature of human matrimonial behavior in these birds for our comfort.
Peaceful family and community life, however, does not imply silence. Wilson wrote: “The noise is almost unceasing. From a distance it is like a whistling roar, and when we looked down upon the two hundred acres swarming with shouting penguins and their whistling, piping chicks, one was reminded of nothing so much as a rink with a thousand chattering skaters.”
Turns are taken siting on the nest and there is quite a ceremony when the guard is relieved, when the two birds rub necks together and softly cackle. Once off duty the freed birds gather in groups at the ice foot to frolic and chatter, each one urging some other to make the first plunge. Once it goes, the others follow in quick succession, though usually after a hasty glance to see if number one has encountered a waiting sea leopard. This is their worst enemy under water —more so than killer whales, which prefer seals. All danger, apart from man, has come to them from the sea, and it is hard to drive the penguins into it.
Once in the water, penguins progress by porpoising, traveling below the surface for ten to thirty yards and then shooting into the air in an are of seven or eight feet, to vanish again with hardly a ripple. For the most part they feed on the opossum shrimp, the krill of whales, and enjoy it so much they will gobble until well distended and then, like Romans at a banquet, vomit and start all over. When finally full, or when scared to death, they head for the ice, break surface thirty or forty yards away to appraise the distance, submerge, and drive for the landing. At the base of the ice, with marvelous accuracy they shoot out of the water erect like a jack-in-the-box and land standing on ice five feet above the sea.
THE birds that Sir Francis Drake and Sir John Hawkins saw, when entering the Strait of Magellan, were the Jackass, black and white harlequins with a wicked black bill. On land or sea they bray like jackasses and have much less sense. They burrow into unfrozen ground to make their nests, but travel far along both Atlantic and Pacific shores at other times. Robert Murphy thinks the ancient Magellanic penguins were the home stock from which some have reached halfway round the world down wind, down current .along the oceanic routes of the Humboldt Current to Peru and the Galápagos, and east with the West Wind Drift to South Africa and the islands of the Indian Ocean.
Even though nests are made in burrows, pebbles are still brought in, without apparent purpose. Maybe the pebbles are like diamonds: they signify a lot, but when all is said and done they are only pretty little stones. In another way, however, the pebbles may have meaning. Jackasses travel fast in the water more than twelve knots — in search of cuttlefish, and old-timesealers and more than one modern observer have said they swallow pebbles as ballast when they go to sea and eject them on their return home. ‘These may be the pebbles in the burnow.
Perhaps the Rock Hoppers, or Jumping Jacks, belong most to the sea and look the silliest on land. Half impish, half scared, with puffed cheeks, crimson eyes, and a shining black crest, they step uncertainly with feet lifted high and have to jump to get anywhere in a hurry. They do not even dive into the water, but jump in feet first from the ledges. They spend so much time at sea that they have been found with barnacles growing on their toes, and encircle the world in the west wind zone.
When Captain Cook first discovered South Georgia, the Forsters went ashore and brought back two kinds of penguins, the King and the Johnny, both of the west wind zone. Johnnies are timid, but they suggest something of the past. They are climbers, and cross perfectly good ground near the sea and trudge wearily up the hillsides to make their nests near the summits of shelterless ridges. There is nothing to be gained by this at present, though it may have made sense at one time. South Georgia, for all its present icy bleakness, was once buried under an even greater cap of ice, and during the long period immediately following its complete glaciation very little breeding territory could have been available. What bare rock there was would have been the rocky ridges separating the ice-filled valleys. The Johnnies have simply held on to the old instinct of climbing to the ridges to find something less disconcerting than ice upon which to hatch an egg. So they go on raising the feet high at every step, with heads thrust forward to see where thes’re going. After all, ws’re hardly out of the ice age yet, and in South Georgia at the time of Cook and Forster the glaciers were even larger than they are now. Moreover, the lower levels would have been held by the seals and the bigger and stronger King penguins.
Only a little smaller than the Emperors, the Kings have stature, dignity, and color. It has been their fate to suffer more senseless slaughter at the hands of white men than have any other kind. All the residents of the last rookery in West Falkland were boiled down by a shepherd to get oil for waterproofing the roof ;l his house— which puts a higher value on the survival of a man than was ever intended. The bird still survives on South Georgia and the West Wind Islands, but not in the old numbers.
King penguins breed on low ground among the tussock grass or on bare and bleak moraines with snowbanks and a glacial torrent close at hand. They might do better, but once again it may be a case of behaving as if the ice age were still in full force; for the Kings, like the Emperors, hold the egg in a pouch at the base of the belly even though it is easier now to avoid ice than find it.
So we return to the Emperor. Of all birds it is the most truly Antarctic, the tallest, heaviest, biggest-boned penguin alive, standing as high as a man’s chest and, except at the Scotian Arc. remaining always within the Antarctic Circle. Yet for all its size and weight, it can shoot up from a depth of water and land feet first upon ice its own height above the surface. It is a powerful bird. Five seamen from the whaler Balaena caught one and tried to hold it down, but were scattered like ninepins. When at last they managed to strap two leather belts around its body, and stood back for a deep breath, the Emperor did the same and burst the belts.
West Wind birds have short winter days in which to fish, but the Emperors live through six months of darkness. All through the polar night the loud metallic trumpeting of the Emperors can be heard afar, and throughout that long and bitter darkness they cuddle their eggs and raise their young. With the coming of light in the spring it is all over and they are off fishing from their ice rafts. The great problem is not how to produce enough eggs but how to incubate them and raise the chicks. The procedure is clear enough.
This is what happens. Only a very small fraction of the Emperors breed during any one winter, but all individuals of either sex, mated or not, have a warm pouch and a warm heart for any exposed egg or chick. The whole community feels broody. Even a lump of ice or a dead and frozen chick is better than nothing, and father, mother, or foster mother tucks its egg on to its feet clear of the ice, within the folds of the pouch, next to warm bare skin. The system works, and enough offspring are raised each black winter in their icy retreats to maintain the population.
We have a little information about how it works, though not from studies on inaccessible Emperors. Recent research on fowls, pigeons, and rats suggests that it is all a matter of glands and hormones. The hormones of the pituitary gland beneath the brain seem to be responsible. One of the pituitary secretions stimulates the ovary and regulates the egg production. Another puts a check upon the process and at the same time induces broodiness. Injection of the hormone will cause a virgin rat to cuddle the young of another. In birds it is obvious that egg-laying must stop before broodiness begins, and these two pituitary secretions determine that it happens this way. All that needs to happen to Emperors is an excessive production of the second and a partial suppression of the first secretion, so that few eggs are laid but there is a superabundant broodiness.
Three general views concerning penguin origin are generally held, although none is new, and all three recognize that in some ways penguins are so unlike any other birds their separation from the rest must have happened a very long time ago. One view would derive the penguins directly from birdlike reptiles that had never learned to fly, another from flying birds so ancient it is foolish to look for connections with any other kind, and the third from a remote but common ancestral stock from which cormorants and their relatives also came. The first means that the ancestral bird took to water and became perfected as a swimmer without ever having flown; the second, that the birds once flew but became grounded and then converted a degenerate wing into a swimming organ; and the last implies that a flying sea bird became an underwater flyer without reference to the land at all.
What the Emperor eggs and all studies of penguin anatomy emphasize is that the penguin is all bird, with typical flight mechanism and no sign of degeneracy. So out goes the running reptile theory.
The second theory had the support of the late W. D. Matthew, one of the great of the American Museum. It has a strong appeal because of the pictures it calls up. It proposes that the ancestors of penguins flew to the land of Antarctica a long time ago, found no enemies or competitors or ice, and like so many other island birds having no need to fly, became too heavy in body and small in wing to do so. In the course of time, as the land became colder, some of them took to making offshore fishing expeditions and used the short wing as a flipper. When the ice age finally arrived and the whole region was buried under the icecap, only the fishing birds survived. It’s all very beautiful and I have dreamed on it at night, but Simpson offers the remaining theory in a streamlined manner that is utterly convincing.
There are several striking features concerning penguins which have to be explained. The foremost, of course, is the type of swimming, which is submarine flying, and it seems that the penguin flipper has never stopped being a wing but has only changed from beating air to beating water. This in itself requires a change from a long and broad weight-lifting blade well feathered to grasp the unsubstantial air, to a short, narrow, sturdy one that can be driven hard and fast against resisting water. All the changes in the wing and chest come from this.
Diving petrels are in many ways like penguins, except that they can still fly in the air. When molting their quill feathers they cannot fly at all, but are still able to use their wings under water and catch their food as usual. They have in fact carried underwater flight just as far as it can go without losing aerial flight altogether, and Simpson argues that at this point a bird is compromised. The diving petrels have balanced one medium against another, and to go any further with underwater flight would mean loss of aerial flight. This the penguins did; the advantages of perfecting submarine flight outweighed those of aerial flight, and they have gone all the way to perfection below the surface. With it has come the streamlining of the body, a change in nature of wing feathers, and the peculiar placing of the legs, all leading to underwater speed. Insulation of the body by downlike feathers and by accumulation of blubber is part of the aquatic adaptation, not a relic of polar exposure. The peculiar method of walking upright on land is the natural consequence of the swimming function.
Simpson thinks that penguins took to the sea, not to escape terrestrial enemies or because food failed in their Antarctic home—the two most popular theories — but like other oceanic birds, because the fish, squid, and crustaceans in the seas around them were so abundant as a source of food. They became specialists in catching it in the cooler southern waters, and bred on the islands of the West Wind Drift and even on the American mainland. Their greatest enemies came from the sea, not the land; and it is this fear, he thinks, that makes them climb hills, to get away from dangerous beaches where sea leopards can still catch them.
This is the heart of it. It leaves the Emperor in a different light — not as the last embittered monarch clinging forlornly to his frozen realm, but as a polar explorer from a more temperate earth, invading the ice barrier and holding fast to his encampments.