News from College Station, Texas

INHERITANCE IN THE HONEY BEE 

MORE or less time has been devoted by the writer, during the past four years, to a study of inheritance in the honey bee, as a project under the Adams Fund. Innumerable obstacles to the progress of this investigation have presented themselves, but sufficient data have accumulated to justify the announcement of a few interesting points. 

The matings have been made, for the most part, at an isolated mating station on the Gulf Coast prairie, about forty miles northwest of Houston, Texas. The location of the station is almost ideal for this purpose, for there are no trees or shrubs affording shelter for bees and no bees occur except those purposely taken to the mating station. 

The matings thus far have been confined to crosses between the Italian and Carniolan races. As is well known, the pure bees of the former race are distinctly yellow, while those of the latter are more or less gray, but always, when pure, devoid of yellow color. For the primary crosses stocks were selected which had been under observation for several generations without having shown any indication of impurity. 

Pure Italian queens mated to Carniolan drones produce workers and queens which are indistinguishable, so far as color is concerned, from the parent Italian stock: that is, in the F1 generation of this, the "primary," cross, the yellow color is completely dominant. In the reciprocal cross, in which Carniolan queens are mated to Italian drones, the yellow color is also dominant, but not as completely so as in the primary cross: the F1 queens and workers show nearly, but not quite, as much yellow color as the parent Italian stock. The significance of this in practical bee breeding is at once apparent. 

For years professional queen breeders have assumed that if an Italian queen throws workers which show the typical Italian coloring it is prima facie evidence that she has been purely mated. From the above results it is evident that such is not necessarily the case, for such a queen might have mated to either an Italian or Carniolan drone (or even, presumably, to a black drone), and in either case her workers would have the typical Italian color. The purity of an Italian queen's mating therefore can not be determined by an examination of her workers. Further reference to this is made below. The production of yellow workers by a pure Carniolan queen, on the other hand, immediately stamps her as having been impurely mated. 

There is also excellent evidence as to the inheritance of characteristics other than color. For example, the marked proclivity of the Carniolans to use wax instead of propolis for sealing crevices, fastening frames together, attaching hive covers to frames, etc., comes dominantly to the surface in the F1 generation of the primary cross. In the F1 generation of the reciprocal cross this trait is also much more in evidence than in the pure Italian race, though not as completely dominant as in the case of the primary cross. 

It seems to be a well established law of heredity that an individual always produces gametes of the same kind as those of which it is itself composed. With this law the queen bee appears to comply without exception. As the drone is produced parthenogenetically he is essentially a gamete and behaves as such in inheritance, at least so far as the color factor is concerned. Pure Italian queens mated to Carniolan drones produce only Italian drones; and Carniolan queens mated to Italian drones produce only Carniolan drones. This is strictly in accordance with the theory of Dzierson. However, the daughters of Italian queens which have mated to Carniolan drones produce both Italian and Carniolan drones, produce them in equal numbers, and do not produce any other kind. The F1 queens of the reciprocal cross likewise produce drones of these two kinds and in equal numbers. 

This is in accordance with the theoretical expectation under Mendelian law. If the constitution of a pure Italian queen be represented by II and of a pure Carniolan queen by CC, the former will produce gametes I and I, and the latter, gametes C and C, these being Italian and Carniolan drones, respectively. A hybrid queen, however, has the constitution IC and produces gametes I and C in equal numbers, these of course materializing as Italian and Carniolan drones. The practical application of this is that the only test of an Italian queen's mating is found in the color of the drones produced by her daughters. 

Another interesting consideration is that the production of an F1 drone seems to be an impossibility and this, in turn, makes the production of a strict F2 generation look like another impossibility. Beekeepers will at once argue that drones intermediate in color occur in nature, and such is the case. However, drones from purely mated queens are known to vary widely in color and this may possibly explain the occurrence of intermediate coloring. We are still in ignorance regarding the causes of this variation, and it is hoped that further data from the mating station will throw more light on this as well as on other phases of this interesting problem. 

WILMON NEWELL 
COLLEGE STATION, TEXAS, 
December 18, 1914	

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