Genetics of Domesticated Behavior in Dogs and Foxes - Genetics and the Behavior of Domestic Animals - page 362

requires the puppy's separation from the family before the eyes open and
intense socialization with a human caregiver ( Coppinger and Coppinger,
2001 ). Competence of dog and hand-reared wolf puppies in their interaction
with humans was tested in multiple tests at 3, 4, and 5 weeks of age ( Gacsi
et al., 2005 ). Significant differences in their behavior have been recorded at
each time point. Dog puppies showed more communicative behavior with
humans. Wolf puppies were more often aggressive to humans and more often
demonstrated avoidance behavior ( Gacsi et al., 2005 ).
These reviewed experiments argue for a domestication hypothesis ( Hare
et al., 2002 ) proposing that canine competence in interaction with humans
has been acquired in the course of long-term selection for communicative
skills. Differences between dogs and wolves in their skills of communication
with humans strongly suggest a genetic basis for these behaviors. Early
socialization improves the competence of wolves for interaction with humans
but a dramatic difference in wolf and dog behavior remains ( Coppinger and
Coppinger, 2001 ). Variation in social skills among individuals in each spe-
cies, domesticated and wild, is caused by a complex interplay of genetic
determinants, life experiences, and environmental factors. Selection for spe-
cific behaviors can lead to genetically determined modifications of these
behaviors, furthermore, it can lead to unexpected modifications of other
behavioral aspects as well.
ANALYSIS OF TEMPERAMENT TRAITS IN DOGS
Selection for breed-specific behaviors has clearly played an important role in
the course of the formation of the working breeds of dogs. Although reliable
historical records on breed origins barely exist for most breeds, there is
substantial evidence that breed formation was associated with cultural and
economical developments in human societies ( Clutton-Brock, 1995; Willis,
1999 ). Modern breeds were officially registered relatively recently, less than
200 years ago, but a gamut of breeds recognized for their unique behavioral
skills had existed for a much longer period of time ( Leighton, 1910 ). Dogs
with similar working skills but differences in terms of the specific functions
they served as well as differences in appearance were recognized as indepen-
dent breeds and received official breed standards when registries were cre-
ated by dog clubs ( AKC, 2006 ; Dalziel, 1897 ). The migration of Europeans
and their dogs to the New World promoted the formation of new working
breeds descended from the old breeds or their crosses, incorporating new
combinations of desirable skills which were better adapted to new needs and
places ( Clark, 2003; Cummins, 2002; Huson et al., 2012 ).
The development of herding breeds is inevitably linked to the growth of
livestock farming. Herding breeds differ among the geographical regions, as
well as the species they herd and the types of tasks they perform ( Combe,
1987 ). Genetically, working sheepdog breeds that originated in Great Britain