Are the Effects of Training Inherited?—Breeders and trainers very commonly believe that the offspring of trained animals inherit in some measure the effects of the training. Thus the increased speed of the American trotting horse is often pointed to as strong evidence of such transmission. According to W. H. Brewer, the earliest authentic record of a mile in three minutes was made in 1818. The improvement, approximately by decades, from that time was as follows:
| During | 1st | decade | after | 1818, | improved | to | 2:34 |
| 2nd | " | " | " | " | " | 2:31½ | |
| 3rd | " | " | " | " | " | 2:29½ | |
| 4th | " | " | " | " | " | 2:24½ | |
| 5th | " | " | " | " | " | 2:17½ | |
| 6th | " | " | " | " | " | 2:13½ | |
| 7th | " | " | " | " | " | 2:08½ |
By 1892, the date of Professor Brewer’s publications (See Agricultural Science, Vol. 4, 1892) the record had reached 2:08½. Since then it has been lowered still further.
On the face of it this looks like a good case of inheritance of training, and Brewer himself believed it such. If so this would mean that colts of a highly trained trotter would be faster than they would have been if their parent had remained untrained. It is impossible to get positive proof in the case of any trained horse since there is no way of establishing just how speedy the progeny would have been had the parent remained untrained. If it could be shown that colts sired by a trotter late in life were on the whole faster than those sired by the same father when younger and as yet not highly exercised in trotting, then the facts might give some evidence of value, but unfortunately no such records are available.
On the other hand, even ignoring the fact that improvement in track and sulky are probably the biggest items in the shortening of records in recent times, selection instead of inheritance of the effects of training will equally well account for any innate progress in trotting. And since, as pointed out by Professor Ritter, there are even more striking cases of similar improvements in other fields, such as college athletics, where the factor of use-inheritance is entirely precluded, it is wholly unnecessary to postulate it in the case of the trotter.
For example an inspection of the records of college athletics for the last thirty-five years in running, hurdling, pole-vaulting, jumping, putting the shot, etc., shows on the whole a steady advance year by year. Moreover, the greatest improvement has occurred in those events in which skill and practise count for most together with selection of the inherently ablest candidate for the events. But in the case of athletics the improvements shown in thirty-five years have all come within a single generation and hence the inheritance of the effects of training is ruled out as a factor. Selection and improved training are the only factors operative.
In the case of the trotter inheritance undoubtedly has also been a factor, but inheritance based on selection of what the race-track has shown to be the speediest individual, not inheritance of the effects of training. In other words, horses which have shown the capacity for being trained to the highest degree of speed have naturally been selected as sires and dams and so through selection generation after generation a speedier strain has gradually been established.
Instincts.—When we turn to the realm of mental traits, particularly of instincts, we meet with a whole host of activities which are frequently pointed to by transmissionists as examples of inherited acquirements. Thus according to them, habits at first acquired through special effort ultimately become instinctive, or according to some, instinct is “lapsed intelligence.” Instances often cited are the pointing of the bird-dog, the extraordinary crop-inflation of the pouter-pigeon, or the tumbling of the tumbler pigeon. We can not stop to discuss these cases beyond pointing out as many others have done that practically all dogs have more or less of an impulse to halt suddenly, crouch slightly and lift up one fore-foot when they scent danger or prey, that all pigeons pout more or less, and that practically all show more or less instincts of tumbling when pursued by a hawk. Thus in all of these cases the fundamental germinal tendency is already at hand for the fancier to base his choice on and thus through selection build up the type desired. Just as in the fan-tailed pigeon, by repeatedly selecting for breeding purposes individuals which showed an unusual number of tail-feathers he has built up a type with an upright, fan-like tail having many more feathers than the twelve found in the tail of the ordinary pigeon, so by similar procedure in the case of other forms he has markedly enhanced certain features. The idea of instincts being “lapsed intelligence” is so clearly and concisely criticized in an article by the late Professor Whitman[4] that I can not do better than quote an excerpt. His views to the contrary are as follows:
“The view here taken places the primary roots of instinct in the constitutional activities of protoplasm and regards instinct in every stage of its evolution as action depending essentially upon organization. It places instinct before intelligence in order of development, and is thus in accord with the broad facts of the present distribution and relations of instinct and intelligence, instinct becoming more general as we descend the scale, while intelligence emerges to view more and more as we ascend to the higher orders of animal life. It relieves us of the great inconsistencies involved in the theory of instinct as “lapsed intelligence.” Instincts are universal among animals, and that can not be said of intelligence. It ill accords with any theory of evolution, or with known facts, to make instinct depend upon intelligence for its origin; for if that were so, we should expect to find the lowest animals free from instinct and possessed of pure intelligence. In the higher forms we should expect to see intelligence lapsing more and more into pure instinct. As a matter of fact, we see nothing of the kind. The lowest forms act by instinct so exclusively that we fail to get decided evidence of intelligence. In higher forms not a single case of intelligence lapsing into instinct is known. In forms that give indubitable evidence of intelligence we do not see conscious reflection crystallizing into instinct, but we do find instinct coming more and more under the sway of intelligence. In the human race instinctive actions characterize the life of the savage, while they fall more and more into the background in the more intellectual races.”
For further discussion of this field the reader is referred to an excellent chapter on “Are Acquired Habits Inherited?” in C. Lloyd Morgan’s book, Habit and Instinct.