INHERITANCE IN CANARIES. 



A. STATEMENT OF PROBLEM. 



The objection has been raised that much of the material used in 

 studies of heredity has been long under domestication, in consequence 

 of which, first, extensive hybridization has occurred, and, secondly, 

 characteristics of an "abnormal" sort have been preserved, and, as 

 a result, conclusions drawn from such material can not properly be 

 applied to feral species as they are evolving "in nature." It is 

 extremely doubtful if this objection has any validity, as I have argued 

 elsewhere (1906). Nevertheless it is well to study heredity widely and 

 to include in the study some undomesticated and semi-domesticated 

 species. On this account, four years ago I began the breeding of certain 

 cage-birds and especially the canary bird {Sermus canarius). 



The canary is, it is true, a semi-domesticated animal. I say semi- 

 domesticated, for in domestication there are all degrees. The essence 

 of domestication from the standpoint of heredity is long-continued 

 control by man of mating. Many species of birds have been bred 

 in zoological gardens, and various finches — linnets, siskins, goldfinches, 

 bullfinches, etc. — are bred in confinement by fanciers and for commer- 

 cial purposes. Likewise grouse and quail and numerous species of 

 swimming birds have been kept captive through many generations, 

 yet such acclimated animals are ordinarily not regarded as domesti- 

 cated, because the breeding has not been long enough continued nor 

 rigidly enough controlled to produce a number of varieties. Between 

 such acclimated wild species and thoroughly domesticated species, such 

 as poultry, dogs, sheep, and horses, which are hardly to be found in 

 the wild state, the canary occupies an intermediate position. 



The history of the canary in captivity is given as follows:* It 

 occurs as a wild species in the Canary and the Madeira Islands. The 

 wild species agrees in coloration so completely with the captive ' 'green' ' 

 canary with greenish-yellow breast and without white on remiges and 

 rectrices that only a person with precise and thorough knowledge of 

 both can find any certain distinguishing characteristic. After the 

 Spaniards took possession of the Canary Islands in 1478 they brought 

 many of the products of the islands home, and among others these 

 remarkable songsters; but for a long time they were rare in Europe. 



*The history has been written by Bolle. e 



