More Letters of Charles Darwin Volume Ii Part 6

LETTER 420. TO G.J. ROMANES. Down, February 5th, 1880.

(420/1. Romanes was at work on what ultimately came to be a book on animal intelligence. Romanes's reply to this letter is given in his "Life," page 95. The table referred to is published as a frontispiece to his "Mental Evolution in Animals," 1885.)

As I feared, I cannot be of the least use to you. I could not venture to say anything about babies without reading my Expression book and paper on Infants, or about animals without reading the "Descent of Man" and referring to my notes; and it is a great wrench to my mind to change from one subject to another.

I will, however, hazard one or two remarks. Firstly, I should have thought that the word "love" (not s.e.xual pa.s.sion), as shown very low in the scale, to offspring and apparently to comrades, ought to have come in more prominently in your table than appears to be the case. Secondly, if you give any instance of the appreciation of different stimulants by plants, there is a much better case than that given by you--namely, that of the glands of Drosera, which can be touched roughly two or three times and do not transmit any effect, but do so if pressed by a weight of 1/78000 grain ("Insectivorous Plants" 263). On the other hand, the filament of Dionoea may be quietly loaded with a much greater weight, while a touch by a hair causes the lobes to close instantly. This has always seemed to me a marvellous fact. Thirdly, I have been accustomed to look at the coming in of the sense of pleasure and pain as one of the most important steps in the development of mind, and I should think it ought to be prominent in your table. The sort of progress which I have imagined is that a stimulus produced some effect at the point affected, and that the effect radiated at first in all directions, and then that certain definite advantageous lines of transmission were acquired, inducing definite reaction in certain lines. Such transmission afterwards became a.s.sociated in some unknown way with pleasure or pain.

These sensations led at first to all sorts of violent action, such as the wriggling of a worm, which was of some use. All the organs of sense would be at the same time excited. Afterwards definite lines of action would be found to be the most useful, and so would be practised. But it is of no use my giving you my crude notions.

LETTER 421. TO S. TOLVER PRESTON. Down, May 22nd, 1880.

(421/1. Mr. Preston wrote (May 20th, 1880) to the effect that "self-interest as a motive for conduct is a thing to be commended--and it certainly [is] I think...the only conceivable rational motive of conduct: and always is the tacitly recognised motive in all rational actions." Mr. Preston does not, of course, commend selfishness, which is not true self-interest.

There seem to be two ways of looking at the case given by Darwin. The man who knows that he is risking his life,--realising that the personal satisfaction that may follow is not worth the risk--is surely admirable from the strength of character that leads him to follow the social instinct against his purely personal inclination. But the man who blindly obeys the social instinct is a more useful member of a social community. He will act with courage where even the strong man will fail.)

Your letter appears to me an interesting and valuable one; but I have now been working for some years exclusively on the physiology of plants, and all other subjects have gone out of my head, and it fatigues me much to try and bring them back again into my head. I am, moreover, at present very busy, as I leave home for a fortnight's rest at the beginning of next week. My conviction as yet remains unchanged, that a man who (for instance) jumps into a river to save a life without a second's reflection (either from an innate tendency or from one gained by habit) is deservedly more honoured than a man who acts deliberately and is conscious, for however short a time, that the risk and sacrifice give him some inward satisfaction.

You are of course familiar with Herbert Spencer's writings on Ethics.

(422/1. The observations to which the following letters refer were continued by Mr. Wallis, who gave an account of his work in an interesting paper in the "Proceedings of the Zoological Society," March 2nd, 1897. The results on the whole confirm the belief that traces of an ancestral pointed ear exist in man.)

LETTER 422. TO H.M. WALLIS. Down, March 22nd, 1881.

I am very much obliged for your courteous and kind note. The fact which you communicate is quite new to me, and as I was laughed at about the tips to human ears, I should like to publish in "Nature" some time your fact. But I must first consult Eschricht, and see whether he notices this fact in his curious paper on the lanugo on human embryos; and secondly I ought to look to monkeys and other animals which have tufted ears, and observe how the hair grows. This I shall not be able to do for some months, as I shall not be in London until the autumn so as to go to the Zoological Gardens. But in order that I may not hereafter throw away time, will you be so kind as to inform me whether I may publish your observation if on further search it seems desirable?

LETTER 423. TO H.M. WALLIS. Down, March 31st, 1881.

I am much obliged for your interesting letter. I am glad to hear that you are looking to other ears, and will visit the Zoological Gardens.

Under these circ.u.mstances it would be incomparably better (as more authentic) if you would publish a notice of your observations in "Nature" or some scientific journal. Would it not be well to confine your attention to infants, as more likely to retain any primordial character, and offering less difficulty in observing. I think, though, it would be worth while to observe whether there is any relation (though probably none) between much hairiness on the ears of an infant and the presence of the "tip" on the folded margin. Could you not get an accurate sketch of the direction of the hair of the tip of an ear?

The fact which you communicate about the goat-sucker is very curious.

About the difference in the power of flight in Dorkings, etc., may it not be due merely to greater weight of body in the adults?

I am so old that I am not likely ever again to write on general and difficult points in the theory of Evolution.

I shall use what little strength is left me for more confined and easy subjects.

LETTER 424. TO MRS. TALBOT.

(Mrs. Emily Talbot was secretary of the Education Department of the American Social Science a.s.sociation, Boston, Ma.s.s. A circular and register was issued by the Department, and answers to various questions were asked for. See "Nature," April 28th, page 617, 1881. The above letter was published in "The Field Naturalist," Manchester, 1883, page 5, edited by Mr. W.E. Axon, to whom we are indebted for a copy.)

Down, July 19th [1881?]

In response to your wish, I have much pleasure in expressing the interest which I feel in your proposed investigation on the mental and bodily development of infants. Very little is at present accurately known on this subject, and I believe that isolated observations will add but little to our knowledge, whereas tabulated results from a very large number of observations, systematically made, would probably throw much light on the sequence and period of development of the several faculties. This knowledge would probably give a foundation for some improvement in our education of young children, and would show us whether the system ought to be followed in all cases.

I will venture to specify a few points of inquiry which, as it seems to me, possess some scientific interest. For instance, does the education of the parents influence the mental powers of their children at any age, either at a very early or somewhat more advanced stage? This could perhaps be learned by schoolmasters and mistresses if a large number of children were first cla.s.sed according to age and their mental attainments, and afterwards in accordance with the education of their parents, as far as this could be discovered. As observation is one of the earliest faculties developed in young children, and as this power would probably be exercised in an equal degree by the children of educated and uneducated persons, it seems not impossible that any transmitted effect from education could be displayed only at a somewhat advanced age. It would be desirable to test statistically, in a similar manner, the truth of the oft-repeated statement that coloured children at first learn as quickly as white children, but that they afterwards fall off in progress. If it could be proved that education acts not only on the individual, but, by transmission, on the race, this would be a great encouragement to all working on this all-important subject. It is well known that children sometimes exhibit, at a very early age, strong special tastes, for which no cause can be a.s.signed, although occasionally they may be accounted for by reversion to the taste or occupation of some progenitor; and it would be interesting to learn how far such early tastes are persistent and influence the future career of the individual. In some instances such tastes die away without apparently leaving any after effect, but it would be desirable to know how far this is commonly the case, as we should then know whether it were important to direct as far as this is possible the early tastes of our children. It may be more beneficial that a child should follow energetically some pursuit, of however trifling a nature, and thus acquire perseverance, than that he should be turned from it because of no future advantage to him. I will mention one other small point of inquiry in relation to very young children, which may possibly prove important with respect to the origin of language; but it could be investigated only by persons possessing an accurate musical ear.

Children, even before they can articulate, express some of their feelings and desires by noises uttered in different notes. For instance, they make an interrogative noise, and others of a.s.sent and dissent, in different tones; and it would, I think, be worth while to ascertain whether there is any uniformity in different children in the pitch of their voices under various frames of mind.

I fear that this letter can be of no use to you, but it will serve to show my sympathy and good wishes in your researches.

2.VIII.II. s.e.xUAL SELECTION, 1866-1872.

LETTER 425. TO JAMES SHAW. Down, February 11th [1866].

I am much obliged to you for your kindness in sending me an abstract of your paper on beauty. (425/1. A newspaper report of a communication to the "Dumfries Antiquarian and Natural History Society.") In my opinion you take quite a correct view of the subject. It is clear that Dr.

d.i.c.kson has either never seen my book, or overlooked the discussion on s.e.xual selection. If you have any precise facts on birds' "courtesy towards their own image in mirror or picture," I should very much like to hear them. b.u.t.terflies offer an excellent instance of beauty being displayed in conspicuous parts; for those kinds which habitually display the underside of the wing have this side gaudily coloured, and this is not so in the reverse case. I daresay you will know that the males of many foreign b.u.t.terflies are much more brilliantly coloured than the females, as in the case of birds. I can adduce good evidence from two large cla.s.ses of facts (too large to specify) that flowers have become beautiful to make them conspicuous to insects. (425/2. This letter is published in "A Country Schoolmaster, James Shaw." Edited by Robert Wallace, Edinburgh, 1899.)

(425/3. Mr. Darwin wrote again to Mr. Shaw in April, 1866:--)

I am much obliged for your kind letter and all the great trouble which you have taken in sending to all the various and interesting facts on birds admiring themselves. I am very glad to hear of these facts. I have just finished writing and adding to a new edition of the "Origin," and in this I have given, without going into details (so that I shall not be able to use your facts), some remarks on the subject of beauty.

LETTER 426. TO A.D. BARTLETT. Down, February 16th [1867?]

I want to beg two favours of you. I wish to ascertain whether the Bower-Bird discriminates colours. (426/1. Mr. Bartlett does not seem to have supplied any information on the point in question. The evidence for the Bower-Bird's taste in colour is in "Descent of Man," II., page 112.) Will you have all the coloured worsted removed from the cage and bower, and then put all in a row, at some distance from bower, the enclosed coloured worsted, and mark whether the bird AT FIRST makes any selection. Each packet contains an equal quant.i.ty; the packets had better be separate, and each thread put separate, but close together; perhaps it would be fairest if the several colours were put alternately--one thread of bright scarlet, one thread of brown, etc., etc. There are six colours. Will you have the kindness to tell me whether the birds prefer one colour to another?

Secondly, I very much want several heads of the fancy and long-domesticated rabbits, to measure the capacity of skull. I want only small kinds, such as Himalaya, small Angora, Silver Grey, or any small-sized rabbit which has long been domesticated. The Silver Grey from warrens would be of little use. The animals must be adult, and the smaller the breed the better. Now when any one dies would you send me the carcase named; if the skin is of any value it might be skinned, but it would be rather better with skin, and I could make a present to any keeper to whom the skin is a perquisite. This would be of great a.s.sistance to me, if you would have the kindness thus to aid me.

LETTER 427. TO W.B. TEGETMEIER.

(427/1. We are not aware that the experiment here suggested has ever been carried out.)

Down, March 5th [1867].

I write on the bare and very improbable chance of your being able to try, or get some trustworthy person to try, the following little experiment. But I may first state, as showing what I want, that it has been stated that if two long feathers in the tail of the male Widow-Bird at the Cape of Good Hope are pulled out, no female will pair with him.

Now, where two or three common c.o.c.ks are kept, I want to know, if the tail sickle-feathers and saddle-feathers of one which had succeeded in getting wives were cut and mutilated and his beauty spoiled, whether he would continue to be successful in getting wives. This might be tried with drakes or peac.o.c.ks, but no one would be willing to spoil for a season his peac.o.c.ks. I have no strength or opportunity of watching my own poultry, otherwise I would try it. I would very gladly repay all expenses of loss of value of the poultry, etc. But, as I said, I have written on the most improbable chance of your interesting any one to make the trial, or having time and inclination yourself to make it.

Another, and perhaps better, mode of making the trial would be to turn down to some hens two or three c.o.c.ks, one being injured in its plumage.

I am glad to say that I have begun correcting proofs. (427/2. "The Variation of Animals and Plants.") I hope that you received safely the skulls which you so kindly lent me.

LETTER 428. TO W.B. TEGETMEIER. Down, March 30th [1867].

I am much obliged for your note, and shall be truly obliged if you will insert any question on the subject. That is a capital remark of yours about the trimmed game c.o.c.ks, and shall be quoted by me. (428/1.

"Descent of Man," Edition I., Volume II., page 117. "Mr. Tegetmeier is convinced that a game c.o.c.k, though disfigured by being dubbed with his hackles trimmed, would be accepted as readily as a male retaining all his natural ornaments.") Nevertheless I am still inclined from many facts strongly to believe that the beauty of the male bird determines the choice of the female with wild birds, however it may be under domestication. Sir R. Heron has described how one pied peac.o.c.k was extra attentive to the hens. This is a subject which I must take up as soon as my present book is done.

I shall be most particularly obliged to you if you will dye with magenta a pigeon or two. (428/2. "Mr. Tegetmeier, at my request, stained some of his birds with magenta, but they were not much noticed by the others."--"Descent of Man" (1901), page 637.) Would it not be better to dye the tail alone and crown of head, so as not to make too great difference? I shall be very curious to hear how an entirely crimson pigeon will be received by the others as well as his mate.

P.S.--Perhaps the best experiment, for my purpose, would be to colour a young unpaired male and turn him with other pigeons, and observe whether he was longer or quicker than usual in mating.