WackyJacki wrote:I am curious where that information comes from, because I have always read that their digestive systems are virtually identical? I realize that dogs are opportunistic of course.
If you could provide the studies/science behind the differences in their digestive systems and dietary requirements I would be genuinely interested in seeing them. (I'm not saying that to be snarky, I really am curious!)
I struggled to find the exact study, but the nutritionists refer to a study in 2001 published in Science that details the genetics and evolution of dogs, as well as development into 5 separate "lines". There is TONS of research on the genetic co-evolution of dogs and humans...
Here is an excerpt from a conference proceeding that also hints at what I'm speaking of...
Behavioral Genetics Update (CAH3)
Western Veterinary Conference 2005
Karen L. Overall, MA, VMD, PhD, DACVB
Center for Neurobiology and Behavior, Psychiatry Department, School of Medicine, University of Pennsylvania
Philadelphia, PA, USA
Objectives of the Presentation
We now have a sufficiently dense map of the canine genome to begin to ask questions about heritability of types of behaviors. A sequela to this should also be the full and functional investigation of cognition in dogs. Part of this understanding will include the heritability of specific suites of genes that may allow for a more plastic nervous system response in learning.
1. Data from 85 domestic dog breeds indicate that differences among breeds account for about 30% of all genetic variation.
2. When breeds are clustered according to genetic similarities they become groups in patterns that would be supported by breed and the tasks that breeds have been asked to execute, so much of this 30% of variation should be in things that dogs do as parts of jobs, or in their behavior, 'temperament', or tendency to behave in certain ways in certain situations.
3. Although the dog genome is arranged differently than is the human genome, when like sequences are compared, the canine genome maps more closely to the human genome than does the mouse genome. In fact, many of the ~360 canine genetic disorders resemble those seen in humans, and 2/3 of the relevant canine DNA sequences / genes appear to be orthologs of those in humans. These data and conclusions are not surprising. In all likelihood, domestic dogs--which branched off from wolves over 135,000 years ago--were not 'domesticated' by humans, but, instead, co-evolved with them.
Overview of the Issue
Dogs share both foraging mode and a virtually identical social system with humans, and have co-evolved for co-operative work with humans for approximately 135,000 years, with intense selection for specific suites of behavioral traits (e.g., the development of breeds) occurring in the last 12,000-15,000 years. Dogs mirror humans in hallmarks of social development. Recent data indicate that dogs are significantly more comparable to humans than are chimpanzees and wolves with regard to the complex social cognition involved in understanding long-distance signals that indicate where food is hidden. Dogs are further able to communicate this information to other dogs. Also, like humans, dogs suffer from what we recognize as maladaptive anxiety--that which interferes with normal functioning--which was selected against during the co-evolution of dogs and humans.
Dog breeds were developed on the basis of specific work or jobs (e.g., border collies, Australian shepherds, Australian cattle dogs [herding]; Labrador retrievers [retrieving in water]; beagles [alerting for hidden prey]; Jack Russell terriers [tracking and killing small prey], Belgian Malinois [herding, guarding, and flock protection], et cetera). Breeds selected for different behaviors or jobs express different manifestations of extreme anxiety. Understanding how genetics works at the macro and micro level can help us understand these important issues.