Popular Science Monthly/Volume 51/October 1897/The Economic Value of Animals


THE influence which the lower animals have had upon mankind has never been appreciated; had it been, they would have received more consideration at our hands. They not only provide us with food, raiment, and a vast array of industries, but they have been factors in the physical and intellectual development of mankind. The beauty of the birds and insects, the splendid coloring of the fishes and reptiles, the quiet harmonies of Nature and the problems they suggest, have insensibly had a refining effect, and aided in the evolution of the higher and aesthetic senses. In a word, the so-called lower animals have been important factors in producing the high civilization which marks the Caucasian race of to-day.

In glancing at the many forms which pay tribute to our wants and requirements, the larger animals naturally attract the attention; yet the greatest works, the most enduring monuments, are those produced by the smallest and most insignificant creatures. Such are the rhizopods—minute marine forms almost invisible, among the very lowest in the scale of life; literal drops of jelly, yet endowed by Nature with the power to secrete shells of rare and beautiful shapes. So vast are their numbers that it has been estimated that if they are as numerous down to a depth of six hundred feet as they are near the surface, there are more than sixteen tons of calcareous shells suspended in the uppermost one hundred fathoms of every square mile of the ocean.

These countless millions are constantly dying, and their shells when released slowly sink to the bottom in a never-ending rain, filling up the inequalities of the ocean bed, and forming a deposit of ooze at a depth of not over twenty-four hundred fathoms several feet in thickness, beneath which are layers of shells of an unknown depth pressed into a solid mass. A prolific source of this ocean rain is a rich spiked atom which has given its name to the globigerina ooze that is almost universal in the deep sea at a depth within the limitations given.

The tendency of the rain of shells is to fill up ocean beds, cap submarine hills and mountains, building them up until they enter the zone of the reef-building corals. In this way these insignificant creatures have aided in the growth of the globe, and, when the deposits by heat or exposure to air are hardened, they become girders of the crust.

The ooze so deposited either fills up the ocean, or by some upheaval is lifted into the air and in time becomes covered with a forest growth; ages pass, and, by a depression of the crust, the hardened ooze again becomes the bottom of an ocean, subject to another rain of shells; and so the change goes on, and we may trace the rhizopods back to the Archæan time, millions of years ago, their story being told by the limestone deposits alternating between the metamorphic schists of that ancient period—monuments of the part these insignificant creatures have taken in preparing the world for man. The chalk cliffs of England are among the visible evidences of this work, the chalk being formed of rhizopods once deposited at the bottom of a sea, but now reared high above the surface to tell the marvelous story. The city of Paris is built of stone formed by rhizopods and other forms, and the pyramids of Egypt are constructed of the remains of various species of fossil animals; yet how these magnificent works of man pale into insignificance before the unconscious work of these minute animals!

Very near the rhizopods are the sponges; lowly creatures whose skeletons are of great value—their collection and preparation forming a vast industry in many parts of the world; a step higher in life we find the coral polyp, secreting lime and piling up reefs and islands that are important girders of the globe. I have spent days in following a coral reef in the Helderberg Mountains of New York far from the reefs of to-day; and we find evidences of them everywhere in the rocks of early geological times. The great reef of Australia, the populous coral keys of the equatorial Pacific, the State of Florida, a reef of seventy-eight thousand square miles in extent, illustrate the value of this polyp to man.

All these animals have other values. From the rhizopod cliffs of Dover comes chalk, while heat is supposed to have changed the skeletons of sponges into flint, so valuable in many ways. Heat has transposed the old coral reefs into beds of marble; and we have the Capitol at Washington, and all the noble works of art of the old Roman and Grecian masters, carved from the crystallized remains of these lowly creatures.

The shells of the seashore and river all have a direct value; the oyster industry of New York city alone represents a capital invested of over two million dollars, which means the support of thousands of men, women, and children. Even the discarded shells constitute an important branch of trade in themselves. Germany and England use tons of pearl oysters, sending them to us in the form of buttons, cheap ornaments, and other articles. The pearl fisheries of the Persian Gulf pay one million dollars per annum; of Australia, three hundred and eighty thousand dollars; while those of Lower California have produced some of the finest and most valuable pearls during the past two centuries. The collection of abalone shells in the State of California means an income of over fifty thousand dollars to the parties interested, while the sale of the polished shells as curiosities gives employment to many persons. From the whelks a dye is obtained; sepia comes from the cuttlefish or squid; while one species provides the cuttlefish bone of commerce. The smallest worm, which Shakespeare tells us, "will turn, being trodden on," has its place in the economy of life. The phosphorescent worms add to the splendors of the festivals of the nights along our shores, and are among the illuminators of the ocean; as bait they have a relation to the fisheries; leeches have a medicinal value, while the common earthworm is a valuable ally of the farmer. Darwin estimates that there are one hundred thousand earthworms in the upper six feet of every acre of ground in favorable localities, and in New Zealand three hundred thousand. They are continually turning over the soil, dragging down seeds and leaves, and bringing to the surface in some places ten tons of mold to the acre every year, thus performing a valuable service to the agriculturist.

The crustaceans are among the important scavengers of the sea and are also valuable as food for fishes. The collection of crabs, shrimps, and lobsters forms large industries all over the world, contributing directly to the support of man. In Delaware the horseshoe crab is used as guano, while the collection of fossil crabs, as trilobites, is a peculiar industry. The fresh-water cray-fish produces a concretion used as an antacid, well known to chemists. We owe many of the beauties of our summer fields to insects, all of which have their special functions and use. Even the persecuted flea may render man a service by keeping the drowsy watch dog awake, while the mosquito in tropical countries may aid in preventing the human inhabitants from living a continual siesta.

The flies are among the most valuable insect scavengers. The spiders prey upon flies, holding them in check. The silk of the spider is used as a cross line in astronomical instruments, and that of a Bermuda species as sewing silk. Bridge makers have obtained valuable suggestions from these silent workers, from whose web one of the kings of France is said to have made a coat. Grasshoppers and locusts are enemies of civilized man, but are eaten by the Indians, while in the Malay country the dragon fly is considered a delicacy.

The cochineal produces the famous commercial dye, a valuable industry. Manna comes from the puncture of an allied insect, while another insect produces wax. A popular eye powder among the Chinese is made from a fly. The silk industry in the United States, the product of the silkworm, represents a capital of twenty-seven million dollars, and the moths and butterflies perform an equally valuable work in fertilizing flowers, thus insuring the crops. A decoction of oak and other galls of the gall fly is an important ingredient in certain inks. Ants are valuable scavengers, and some produce an acid used in trade. The remarkable honey ants of the Southwest are considered dainties in Mexico and served after dinner alive. In the nests of these ants certain individuals cling to the ceiling, their abdomens filled with honey, which has been given to them by their companions, so they are literally living honey jars, holding the reserve food supply of the others, which they give up on application. The distended abdomen, about as large as a currant, is the luxury of the Mexicans.

Bees have a sterling value the world over and support many men, women, and children. A few years ago a single bee ranch in San Diego County, California, produced one hundred and fifty thousand pounds of honey and wax. The importance of bees, aside from the question of honey, is shown by the fact that it was found impossible to cultivate red clover in New Zealand, as there were no bumblebees to carry the pollen. These are but a few of the benefits we obtain from the insects, the majority of which are generally considered pests.

The story of the economic value of vertebrate life would mean a part of the commercial history of the world, so essential are nearly all of the higher animals to man and his advancement. We may pass rapidly in review the great fisheries of the globe which afford a direct support to thousands, from the salmon canneries of Alaska to the tunny fishermen of the Mediterranean.

The sharks, valuable scavengers, provide the makers of swords, belts, and various fancy articles with leather, the teeth being made into fancy and cheap jewelry. On the New England coast the small sharks or dogfish are in demand as guano, the fisheries giving employment to hundreds of men during the summer months. The oil of nearly all sharks is a commercial commodity, while the shark fin is a delicacy to the Chinese and collected by the ton from Catalina to China.

The torpedo ray has been utilized by science, and the electric catfish of Africa is sometimes employed as a medicine.

The Volga sturgeon fisheries give employment alone to over one hundred thousand persons, while that of our Alaskan coast is an important and growing industry. Helmets are made from the porcupine fish. The oil of the sunfish is valued in medicine. Shagreen comes from various fishes; leather and isinglass from the cod, hake, and haddock, weak and drum fishes; while the scales of the tarpon and parrot fishes are employed in ornamentation. Carp, dace, tench, and other fishes generally considered of little value, produce scales from which artificial pearls are made, and so become factors in a large and growing industry, especially in France. The importance of fishes as food need not be mentioned. In the mere enumeration of useful products of animals but a faint idea can be gained of the vast interests they present. The National Museum, under the direction of the late lamented Prof. Goode, arranged a collection which illustrates the value of fish and fishing in all the details from the jewfish, that is made into boneless cod, to the feather fly, whose manufacture gives employment to hundreds of women and girls in New York.

The products of fish give rise to numerous industries, among which may be mentioned isinglass from the sturgeon; caviare; leather from eelskins, and guano from catfish. Then come the trades associated with the capture of fishes—the dealers in fishing tackle, the builders of fishing boats, the makers of fishhooks, sinkers, and artificial bait being a few that will suggest how the fishes indirectly enter into the life of man and aid in his support.

Passing to the reptiles and their allies, we find the frogs and lizards destroying noxious insects, ridding the gardens and trees of pests. The skin of large snakes is made into leather; that of smaller varieties into belts, hatbands, covering for boxes, etc.; while snake oil is highly valued for various purposes. In South America the white meat of the great boa is esteemed a delicacy. A political economist, whose name I do not recall, has stated that wars are a necessity to kill off the surplus population. This philosopher would probably consider the snakes of India in the light of a benefit, as since 1870 they have destroyed over two hundred thousand natives.

We obtain our real tortoise shell from the hawksbill turtle, the beautiful substance being made into countless articles, forming important industries in themselves. The Florida crocodile and alligator are on the verge of extinction that we may have satchels and the hundred and one objects in this leather which the ingenious makers give us. Every portion of the animal is of value. The teeth are made into jewelry, the oil soothes the rheumatic patient, while alligator musk forms an ingredient in the manufacture of perfumes.

The direct benefits which we obtain from the birds are well known. The egg, poultry, and wild game industry, the sale of pet birds, the extravagant use of plumes and feathers at the dictates of fashion, the sale of birds and eggs for specimens, the manufacture of fly-fishing bait, are but a few industries which afford employment to thousands all over the world and represent the investment of vast sums of money. Some of the peculiar products of birds are leather from the feet of tropic species, the albatross; pipestems from the leg of the latter; quill pens, penguin-feather furs, and penguin skins as fuel at Heard Island; the oil of gulls as lamp oil by Eskimos; leather from the pouch of the man-of-war bird; and tobacco pouches from that of the pelican. In heathen China the beautiful little quail is used by noble ladies to warm the hands in winter, and in civilized America live pigeons are used as a target by our so-called sportsmen. Many birds are becoming extinct, due to the demand for them by exacting fashion. Every hummingbird, bluebird, heron, or curlew in California and Florida has a price upon its head.

A value which birds have to man should not be omitted, namely, their work in distributing seeds, thus aiding in rendering islands habitable for mankind. This can be illustrated by the work of pigeons at the Moluccas. The Dutch destroyed all the nutmeg trees except those on the island of Great Banda, but were obliged to send a yearly commission to cut down the trees which grew from seeds transported to the island in the crops of the fruit pigeons. Coffee and other seeds are transported in the same way.

Among the higher or milk-giving animals there is hardly one that is not of some distinct value to man. The fur-bearers are well known, from the fast-disappearing fur seal to the common cat, over a million skins of which are used every year in the trade and sold as Alaska sable; six million squirrel skins are used by furriers every year, while thousands of common ratskins are employed in the manufacture of kid-glove thumbs. Muskrats contribute three million skins annually to the trade, and musk as well. The skunk, kangaroo, and other little suspected animals are all important factors in trade. Among the singular leather producers are the raccoon, peccary, cat, dog, for drumheads; white whale, which is dressed as kid, velvet, or plush; porpoise, and hippopotamus.

Every portion of almost every animal is available for the requirements of man: parchment from the viscera of seals and bears, gold-beater's skin from those of the ox, and catgut from those of the sheep. The hair of many animals is used in an infinite number of ways, from that of the skunk in fine brushes to that of the badger, dog, camel, hog, and others for coarse kinds. From the hoofs, bones, and horns of animals comes gelatin, used in the manufacture of court-plaster, jelly, and artificial flowers.

The oils of the milk-givers represent a vast interest. Some of the most singular are porpoise-jaw oil, used in lubricating fine watch machinery; manatee and dugong oil and dog oil in the manufacture of kid gloves. From many of these fine soaps are made. Some of our perfumes are obtained from certain animals—as the muskrat, musk ox, civet cat, musk deer, and beaver.

The artist looks to various animals for fine colorings. Ivory black, used in the manufacture of bank-note ink and in fine paintings, comes from bones; while Prussian blue is made from hoofs and refuse hair. The gall produces a dye, and from blood comes the turkey red of printers. The chemist depends upon animals to a large extent. Portions of the dog are used in tanning hides; albumin of the blood in refining sugar and various secretions in printing calico; while the chemist finds pepsin in the stomach of hogs and calves. Phosphorus for matches is taken from bones; the physician obtains his vaccine lymph from cows, by this means saving thousands of lives; while ammonia and lime are common products from bones and horn.

Among the special animals that are of great value to man is the whale. In 1884 a single animal sold for over fifteen thousand dollars, the oil bringing $3,490, the bone $12,230. Besides these products there is the ambergris, a secretion in the intestine; the valuable ivory of the teeth used by the Japanese in their carving; the skin as leather; the bones for knife handles and for various purposes.

The delicate mole is a valuable aid to the agriculturist. An individual will eat twenty thousand grubs in a year, while the fur is highly esteemed. The fur dealers use nearly ten million skins of rabbits and hares a year. Twenty thousand bears are sacrificed yearly, the hides being employed as leather, and even teeth for Indian chisels, knives, and ornaments. In 1880 the trade absorbed seven hundred tons of elephant ivory, one hundred thousand of these noble animals being killed that we might have billiard balls, chessmen, carved figures, and countless other objects for use and ornament.

The furs of animals keep us warm in winter, while the wool of our undergarments comes from another group representing vast industries giving support to thousands of persons.

Statistics in which this paper abounds are dry and uninteresting, but they alone tell the story of man's dependence upon the lower animals. One hundred thousand Persian lambskins are used annually by the trade; six hundred thousand Astrakhans and two hundred English skins—suggestive of an array of workers.

From the goat come mohair, cashmere; while the interesting Angora goat, which has been introduced into California, produces fifteen million pounds of wool per annum; every hoof, hide, and horn has its value in the great world of trade. The camels and their allies produce the hair for shawls and other valuable articles of wear.

The demand for objects of luxury is tending to the extinction of some of our most valuable animals. The buffalo has been almost wiped from the face of the earth, that we might have sport, robes, and buffalo tongue. The five hundred lion skins which the trade uses annually for rugs and leather have marked the royal cat for early extinction; while the rhinoceros, giraffe, tiger, elephant, and many more will doubtless be known to our descendants a century hence by their pictures in books and their remains in the museums of the day.

This great question of the economic value of animals is of radical importance to every citizen. It should secure our thoughtful attention, and be taught in our schools and colleges. We should demand from the Government absolute protection to the fur seal; our humane societies, which have accomplished so much, should extend their good offices to the protection of song birds, the wild game of our forests, and to all animal life.