Gorillas & Chimpanzees

In the meantime Moses has had his supper, and gone to his own little cage, to find shelter from the approaching storm. The curtains are hung up on the side of the cage, from which the tornado is coming. Now the leaves begin to rustle. It is the first cool breath of the day, but it is only the herald of the furious wind that is rapidly advancing. The tree-tops begin to sway. Now they are lashing each other as if in anger; the strong trees are bending from the wind; the lightning is so vivid that it is blinding; the thunder is terrific. One shaft after another, the burning bolts are hurled through the moaning forest. The roar of thunder is unceasing. I hear the dull thud of a falling tree, while the crackling boughs are falling all around me. The rain is pouring in torrents, and all nature is in a rage. Every bird and beast has sought a place of refuge from the warring elements. No sign of life is visible, no sound is audible, save the voice of the storm.

How unspeakably desolate the jungle is at such an hour, no fancy can depict. How utterly helpless a human being is against the wrath of nature, no one can realise, except to live through such an hour in such a place.

On one occasion five large trees were blown down, within a radius of two hundred yards of my cage, and scores of limbs were broken off by the wind, and scattered like straws. Some of them were six or eight inches in diameter, and ten or twelve feet long. One of them broke the corner off the bamboo roof over my cage. The limb was broken off a huge cotton-tree near by, and fell from a height of about sixty feet. It was carried by the wind some yards out of a vertical line as it fell, and just passed far enough to spare my cage. Had it struck the body of it, no doubt it would have been partly demolished, for the main body of the bough was about six inches in diameter and ten feet long. This particular tornado lasted for nearly three hours, and was the most violent of any I saw during the entire year.

Now the storm subsides, but the darkness is impenetrable. I have no light of any kind, for that would alarm the inhabitants of the jungle, and attract a vast army of insects from all quarters. Moses and the boy are fast asleep, while I sit and listen to the many strange and weird sounds heard in the jungle at night The bush crackles near by. It is a leopard creeping through it. He is coming this way. Slowly, cautiously he approaches. I cannot see him in the deep shadows of the foliage, but I can locate him by sound, and identify him by his peculiar tread. Perhaps he will attack the cage when he gets near enough. He is creeping up closer. He evidently smells his prey, and is bent on seizing it.

My rifle stands by my elbow. I silently raise it, and lay it across my lap. The brute is now crouching within a few yards of me, but I cannot see to shoot him. I hear him move again, as if adjusting himself to spring upon the cage. He cannot see it, but he has located me by scent. I hear a low rustling of the leaves as he wags his tail preparatory to a leap. If I could only touch a button and turn on a bright electric light over his head! He remains crouching near, while I sit with the muzzle of my rifle turned towards him, and my hand on the lock. It is a trying moment. If he should spring with such force as to break the frail network that is between us, there could be but one fate for me.

In the brief space of a few seconds a thousand things run through one's mind. Not prompted by fear, but by suspense. Is it best to fire into the black shadows, or to wait for his attack? What is his exact pose? What does he intend? How big is he? Can he see me? And a category of similar questions arise at this critical moment.

A clash of bushes, and he is gone. Not with the stealthy, cautious steps with which he advanced, but in hot haste. He has taken alarm, abandoned his purpose, and far away I can hear the dry twigs crashing as he hurries to some remote nook. He flees as if he thought he was being pursued. He is gone, and I feel a sense of relief.

It is ten o'clock, the low rumbling of distant thunder is all that remains of the tornado that swept over me a few hours ago. The stars are shining, but the foliage of the forest is so dense, that I can only see one here and there, peeping through the tangled boughs overhead. I hear some little waif among the dead leaves, but what it is, or what it wants, can only be surmised.

Another hour is passed, and I retire to my hammock. The sounds of nocturnal birds are fewer now. I hear a strange, tremulous sound up in the boughs of the bushes near the cage. It sounds like the leaves vibrating. It ceases, and begins again at intervals. I listen with attention, for it is very singular. It is a huge python in search of birds. He reaches his head and neck forward, grasps the bough of a slender bush, releases his coil from another, and by contraction draws his slimy body forward. The pliant boughs yield to his heavy weight. The abrasion causes it to tremble, and the leaves to quake.

I fall asleep and rest in comfort, while the dew that has fallen on the leaves gathers itself into huge drops, their weight bends the leaves, and they fall from their lofty perch, striking those far below with a sharp, popping sound. The hours fly by, but in the stillness of the early morning is heard a most unearthly scream. It is a king gorilla. He simply makes every leaf in the forest tremble with the sound of his piercing shrieks.

The dawn again awakes to life the teeming forest, and all its denizens again go forth to join the universal chase for food.

All of these incidents cited are true in every detail, but they did not occur every day, nor did all of them occur on the same day, as would be inferred from the manner in which they are related.

This gives a glimpse of my real daily life in the jungle, but the monotony was often relieved by going out for a day or two at a time, or hunting on the plains, a few miles away. My menu was occasionally varied by a chicken, piece of goat, fish or porcupine; but the general average of it was about as described.

CHAPTER IV

THE CHIMPANZEE

Next to man, the chimpanzee occupies the highest plane in the scale of nature. His mental and social traits, together with his physical type, assign him to this place.

In his distribution, he is confined to Equatorial Africa. His habitat, roughly outlined, is from the fourth parallel north of the equator to the fifth parallel south of it, along the west coast, and extends eastward about half-way across the continent. His range can be defined with more precision, but its exact limits are not quite certain. Its boundary on the north is defined by the Kameroon valley, slightly curving to the north, but its extent eastward is not well known. He does not appear to be found anywhere north of this river, and it is quite certain that the few specimens attributed to the north coast of the Gulf of Guinea do not belong to that territory. On the south, its boundary starts from the coast, at a point near the fifth parallel, curves northward, crossing the Congo near Stanley Pool, pursues a north-east course, to the centre of the Congo State, again curves southward, across the Upper Congo, towards the north end of Lake Tanganyika. Its limits appear to conform more to isothermal lines, than to the rigid lines of geometry.

Specimens are sometimes secured by collectors beyond the limits mentioned, but so far as I can ascertain they appear to have been captured within these limits. There are numerous centres of population. This ape is not strictly confined to any definite topography, but occupies the upland forests or the low basin lands.

In one section he is known to the natives by one name, and in another by quite a different one. The name chimpanzee is of native origin. In the Fiot tongue the name of the ape is chimpan, which is a slight corruption of the true name. It is properly a compound word, the first syllable is from the Fiot word tyi, which white men erroneously pronounce like "chee." It means "small," and is found in many of the native compounds. The latter syllable is from mpâ, a bushman, hence the word literally means, in the Fiot tongue, "a small bushman."

Among other tribes the common name of the ape is ntyigo. The two names appear to come from the same ultimate source. The latter is derived from the Mpongwe word ntyia, blood, hence breed, and the word iga, the forest, and literally means the "breed of the forest." The same idea is involved in the two names, and both convey the oblique idea that the animal is something more like man than other animals are.

There are two distinct types of this ape, and they are now regarded as two species. One of them is distributed throughout the entire habitat described, while the other is only known south of the equator, between the second and fifth parallels, and west of the Congo. Both kinds are found within these limits, but the variety which is confined to that region is called, by the tribes that know the ape, the kulu-kamba, in contradistinction to the other kind, known as ntyigo. This name is derived from kulu, the onomotope of the sound made by the animal and the native verb kamba, to speak, hence the name literally means the thing "that speaks kulu."

In certain points the common variety differs from the kulu-kamba in a degree that would indicate that they belong to distinct species, but the skulls and skeletons are so nearly the same, that no one can identify them with certainty. In life, however, it is not difficult to distinguish them.

The ntyigo has a longer face and more prominent nose than the kulu. His complexion is of all shades of brown, from a light tan to a dark, dingy mummy colour. He has a thin coat of short black hair, which is often described as brown, but that effect is due to the colour of his skin blending with that of his suit. In early life his hair is quite black, but in advanced age the ends are tipped with a dull white, giving him a dingy grey colour. The change is due to the same causes that produce grey hairs on the human body. But there is one point in which they differ. The entire hair of the human becomes white with age, while only the end of it does so in the chimpanzee. In the human, one hair becomes white, while another retains its natural colour, but in this ape all the hairs appear to undergo the same change.

In very aged specimens the outer part of the hair often assumes a dirty, brownish colour, which is due to the want of vascular action to supply the colour pigment, and the same effect is often seen in preserved specimens, for the same reason that the hair of an Egyptian mummy is brown, while in life it was doubtless a jet black. In this ape the hair is uniformly black, except the small tuft of white at the base of the spinal column and a few white hairs on the lower lip and chin. I have examined about sixty living specimens and I have never found any other colour among them only from the cause mentioned. The normal colour of both sexes is the same.

The kulu, as a rule, has but little hair on the top of its head, but that on the back of it and on the neck is much longer than elsewhere on the body, and longer on them than on other apes.

Much stress is laid by some writers on the bald head of one ape and the parted hair on that of another. These features cannot be relied upon as having any specific meaning, unless there are as many species as there are apes. Sometimes a specimen has no hair on the summit of its head, while another differs from it in this respect alone by having a suit of hair more or less dense, and yet in every other respect they are the same. Some of them have the hair growing almost down to the eyebrows, and each hair appears to diverge from a common centre like the radii of a sphere: another of the same species will have the hair parted in the middle as neatly as if it had been combed, while another may have it in wild disorder. The same thing is noticed in certain monkeys, and it is equally true of the human being. As a factor in classifying them it signifies nothing. It may be remarked that as a whole the kulu is inclined to have little hair upon the crown of the head.

Between the two species there is a close alliance, but the males differ more than the females. This is especially true in the structure of certain organs.

The face in youth is quite free from hairs, but in the adult state there is, in both sexes, a slight tendency to grow a light down over the cheeks.

The colour of the skin is not uniform in all parts of the body, especially on the face. Some specimens have patches of dark colour set in a lighter ground. Sometimes certain parts of the face will be dark, and other parts light. I have seen one specimen quite freckled.

It is said by some that the skin is light in colour when young, and becomes darker with age, but such is not the case. It is true that the skin darkens a few shades as the cuticle hardens, but there is no transition from one colour to another, and this slight change of shade is only on the exposed parts.

The kulu has a short, round face, very much like that of a human. In early life it is quite free from hairs, but, like the other, a slight down appears with age. He has a heavy suit of hair on the body. It is coarser than that of the ntyigo, longer, and inclined to wave, giving it a fluffy aspect. The colour is jet black, except a small tuft of white about the base of the spine.

The skin varies in colour less than in the ntyigo, and the darker shades seldom appear. The eyes are a shade darker, and in both species the parts of the eye which are white in man are brown in the chimpanzee, gradually shading off into a yellow near the base of the optic nerve. As a rule, the kulu has a clear, open visage, with a kindly expression. It is confiding and affectionate to a degree beyond any other animal. It is more intelligent than its confrère, and displays the faculty of reason almost like a human being.

One important point in which these apes differ is in the scope and quality of voice. The kulu makes a greater range of vocal sounds than the other. Some of them are soft and musical, while those uttered by the ntyigo are fewer in number and more harsh in quality. One of them resembles the bark of a dog, and another is a sharp screaming sound.

The kulu evinces a certain sense of gratitude, while the ntyigo appears to be almost devoid of this instinct. There are many traits in which they differ, but human beings, of the same family, also differ in these qualities.

The points in which they coincide are many, and after a brief review of them, we may consider the question of making two species of them, or assigning them to the same.

The skeletons, as we have noted, are the same in form, size and proportion. Their muscular, nervous, and veinous systems are the same, except a slight structural variation in the genital organs of the males, and the degree of mobility in certain facial muscles. The character of their food, and the mode of eating it, are the same in each. In captivity they appear to regard each other as one of their own kind, but whether they mate or not remains to be learned.

Such is the sum of the likenesses and differences between the two extreme types of this genus; but with so many points in common, and so few in which they differ, it is a matter of serious doubt whether they can be said to constitute two distinct species, or only two marked varieties of a common species. This doubt is further emphasised by the fact that all the way between these two extremes are many gradations of intermediate types, so that it is next to impossible to say where one ends and the other begins.

In view of all these facts, I believe them to be two well-defined varieties of the same species; they are the white man and the negro of a common stock. They are the patrician and plebeian of one race, or the nobility and yeomanry of one tribe. They are like different phases of the same moon. The kulu-kamba is simply a high order of chimpanzee.

It is quite true that two varieties of one species usually have the same vocal characteristics, and this appears to be the strongest point in favour of assigning them to separate species, but it is not impossible that even this may be waived.

Leaving this question for others to decide, as they find the evidence to sustain them, we shall, for the present, regard them as one kind, and consider their physical, social and mental status.

Whether they be all of one species, or divided into many, the same habits, traits, and modes of life prevail throughout the entire group, so that one description will apply to all, so far as we have to deal with them in general. There are many incidents to be related elsewhere, which apply to individuals of the special kinds mentioned, but for the present the term chimpanzee is meant to include the whole group, except where it may be otherwise specified.

CHAPTER V

PHYSICAL, SOCIAL, AND MENTAL QUALITIES

Physically, the chimpanzee, as we have seen, closely resembles man, but there are certain points that have not been mentioned in which he differs from him, also from other apes. We may here take note of a few of those points.

The model and structure of the ear of this ape are somewhat the same as those of man, but the organ is larger in size, and thinner in proportion. It is very sensitive to sound, but dull to the touch, indicating that the surface is not well provided with nerves. He cannot move it as other animals move theirs by the use of the muscles at its base, but, like the human ear, it is quite fixed and helpless in this respect.

The hand of the chimpanzee is long and narrow. The finger bones are longer, in proportion to their size, than those of the human hand, and slightly more curved in the plane of the digits. One thing peculiar in the hand of the chimpanzee, is that the tendons inside of the hand, which are called the flexors, and designed to close the fingers, are shorter than the line of the bones, and on this account the fingers of the ape are always held in a curve, so that he cannot possibly straighten them into a line. This is probably due to the habit of climbing in which he indulges to a great extent; also to the practice of hanging by the hands. In making his way through the bush, he often swings from bough to bough by the arms alone, and sometimes suspends himself by one arm, while he uses the other to pluck and eat fruit. This characteristic is transmitted to the young, and is found in the first stages of infancy. The thumb is not truly opposable, but is inclined to close towards the palm of the hand. It is of little use to him. His nails are thick, dark in colour, and not so flat as those of man.

Instead of having the great toe in line with the others, it projects at an angle from the side of the foot, something after the manner of the human thumb. The foot itself is flexible, and has great prehensile power. In climbing, and in many other ways, it is used as a hand. The tendons in the sole of the foot are equal in length to the line of the bones, and the digits of the foot can be straightened, but both members are inclined to curve into an arch in the line of the first and second digits.

His habit of walking is peculiar. The greater part of the weight is borne upon the legs. The sole of the foot is placed almost flat on the ground, but the pressure is greatest along the outer edge of it, in the line of the last digit. This is easily noticed where he walks through plastic ground. In the act of walking he always uses the hands, but does not place the palm on the ground; he uses the backs of the fingers instead, sometimes only the first joints are placed on the ground, resting on the nails; at other times the first and second joints are used, while at others the backs of all the fingers from the knuckles to the nails serve as a base for the arm. The integument on these parts is not callous, like that of the palm; the colour pigment is distributed the same as on other exposed parts of the body, which shows that the weight of the body is not borne on the fore limbs, as it is in the case of a true quadruped, but indicates that the hand is only used to balance the body and shift the weight from foot to foot, while in the act of walking. The weight is not equally distributed between the hands and the feet.

His waddling gait is caused by his short legs, stooping habit and heavy body. All bipeds with stout bodies and short legs are predisposed to a waddling motion, which is due to the wide angle between the weight and the changing centre of gravity.

The chimpanzee is neither a true quadruped, nor a true biped, but combines the habits of both. It appears to be a transition state from the former to the latter, and a vestige of this habit is still to be found in man, whose arms alternate in motion with his legs in the act of walking, which suggests the idea that he may, at some time, have had a similar habit of locomotion. Such a fact does not show that he was ever an ape, but it does point to the belief that he has once occupied a like horizon in nature to that now occupied by the ape, and that having emerged from it, he still retains traces of the habit.