Nov. 1, 1911 



631 



®[PD°(§©ra: 



INBREEDING. 



Some of its Possibilities; how we can Develop De- 

 sirable Characteristics in Bees ; the Editor's 

 Scheme to Mate Drones and Queens on an Island. 



BY H. D. TENNENT. 



Mr. Raleigh Thompson asserts, Nov. 15, 

 1910, p. 786, that the laying or individual re- 

 production of bees can not exist without 

 swarming or colony reproduction. They 

 certainly do not appear on the surface to be 

 more closely connected than the laying and 

 sitting of poultry and other associated func- 

 tions of living things in which just as great 

 variations occur. Since nothing else with 

 which we have to do has the same complex 

 system of reproduction we have nothing ex- 

 actly analogous to the swarmless bee; but 

 there is no lack of cases in which just as 

 serious and fundamental variations have oc- 

 curred. 



The production of flowers and setting of 

 seed are certainly closely related functions 

 of plants, yet we have numerous ornamental 

 plants which bloom profusely but produce 

 no seed. The sole use of fruit to trees and 

 plants is to secure distribution of their seed; 

 yet there are varieties of oranges, pineapples, 

 apples, pears, grapes, tomatoes, and persim- 

 mons, nearly or quite seedless. If animals 

 could be propagated by division it would 

 not be much trouble to form barren breeds. 

 As plants, animals, and insects, so far as 

 investigated, are (in the main) subject to 

 the same laws of heredity, such comparisons 

 are not so far amiss as might at first seem. 

 In experiments with potatoes, constant se- 

 lection of varieties which have devoted the 

 most energy to the production of tubers has 

 resulted in some which seldom or never pro- 

 duce seed, though themselves raised from 

 seed-balls. It is quite probable that similar 

 breeding from the colonies which produce 

 the most honey would lead, in time, if wide- 

 ly practiced, to the inclusion of non-swarm- 

 ing strains if such are not already in exis- 

 tence. 



The statement that the swarming instinct 

 can not be eliminated by keeping bees for 

 any length of time, under conditions un- 

 favorable to its exercise, is quite in line w' ith 

 the results of modern investigation. It was 

 formerly thought that the mere disuse of a 

 part or function would in time lead to its 

 being left out entirely; but it has since been 

 shown that the complete removal of a part 

 for many generations has no effect on its in- 

 heritance. Such changes must ordinarily 

 come from sports or mutations affecting the 

 germ, which occasionally occur, but the 

 causes of which are as yet unknown and be- 

 yond the control of man. 



If such a variation were once found to ex- 

 ist in transmissible form, its perpetuation, 

 though involving considerable trouble, 

 would certainly not be impossible. It is 



very rare that nature sets uj) any impass- 

 able barriers to the perpetuation of propa- 

 gable variations. Except by the rare chance 

 of another sport, a true sport can not revert 

 back to the original type unless crossed with 

 it or with some other strain derived from it, 

 and, in the great majority of cases, is not 

 destroyed by such crossing. This is the 

 conclusion reached by modern investigators. 

 If unusual length of tongue, as mention- 

 tioned by the editor, Dec. 1, p. 748, behaves 

 as do hereditary characteristics in nearly all 

 cases among other forms of life, its hybrids 

 with the normal form will, if mated togeth- 

 er, give a proportion having tongues just as 

 long as in the original sport, and j^ure for 

 the characteristic. If, in the heredity of 

 bees, differences in tongue-length should 

 happen to belong to the rare class of cases 

 known as non-segregating, in which hybrids 

 breed true to the intermediate or hybrid 

 form, as with the long ears of the lop rkbbit 

 in its crosses with other breeds, then the 

 quality might indeed be lost by continued 

 crossing with the common form. 



But proved cases of this kind are very 

 rare. Such characteristics as the various 

 combs of chickens, the taillessness of the 

 Manx cat, and the rumpless or "bunty" 

 fowl, separate jierfectly from their hybrids, 

 and may be combined with any unrelat- 

 ed characters of other breeds. The same 

 is true, to some extent at least, with 

 long and short hair among animals, as is 

 also apparently the case with the less tan- 

 gible qualities, such as the trotting and pac- 

 ing gaits of horses and the sitting and non- 

 sitting dispositions among poultry. 



But in either case, if this queen, men- 

 tioned p. 748, Dec. 1, had been in some iso- 

 lated locality, "long-tonguers " might now 

 be selling at rates which would make an 

 ordinary queen "look like thirty cents." 

 The drones of the original queen might, of 

 course, not carry the characteristic, in which 

 case they w^ould have to be left out, and the 

 drones of her daughters and purely descend- 

 ed queens used for quickest results. 



It seems to me that the stand taken by 

 some concerning the possibilities in the 

 modifying of bee nature is too conservative 

 for these days of seedless fruit, thornless 

 cacti, and wiiite blackberries. The difficul- 

 ties in the way of perpetuating unusual 

 variations in bees may be discouraging to 

 those ordinarily situated; but there are, no 

 doubt, many readers of Gleanings located 

 within reach of islands, or otherwise isolated 

 places, who, by a little trouble, could abso- 

 lutely control drone parentage, and so might 

 secure valuable results in improvement. 



Should inbreeding have any unavoidable 

 injurious effects, ordinarily by occasional 

 crossing with other breeds followed by suit- 

 able selection, the strain could be kept vig- 

 orous without losing its valuable qualities. 

 If the characteristic should not separate 

 from its hybrids, it might be necessary to 



