The size of dogs is a known factor for dog’s longevity. Smaller dogs tend to outlive bigger dogs. However, body size and mass are not the only factors that determine how long a dog will live. Fascinatingly, according to a new study, a dog’s personality influences its longevity. This might intriguingly promote better understanding of how animals evolve naturally.
Studies conducted on ants to apes or insects to animals, has projected that every single species have their own respective personality. There are those who are aggressive while others might be timid. Natural biologists have suggested that character is something that is built up during a life history. The underlying thought is that aggressive and bold animals tend to use more energy and hence their lives are shorter. On the other hand, animals which are calm tend to reproduce later in life and therefore, live longer.
Evolutionary experiments are tremendously hard to conduct on a living organism that survives longer than a fruit fly. However, Vincent Careau, an evolutionary biologist from Université de Sherbrooke in Canada proposed to use dogs in evolutionary experiments. According to Careau, this new evolutionary prototype for experiments is bringing new ideas to evolutionary studies. There are several categories of dogs, with diverse traits. This has given scientists a new agenda to discover; Dogs sitting near the sofa; dogs managing a herd of sheep; and notorious dog chasing foxes to the peril.
Assimilating data from earlier studies, Careau could analyse the differed breeds’ energy expenditure as well as longevity factors. The body size was a major factor accounted in the study, but apart from that Careau examined the relation of obedience, aggressiveness and activity.
In the June issue of The American Naturalist, Careau revealed that dogs that were more obedient had a greater survival chance. For example, the German Shepherds & bichon firsés, lived longer than expected when relying on their body size. However, dogs such as Pomeranians and beagles, that are less easy to tame and to teach, tend to die earlier than other dogs of the same size..
There was an alike association identified for energy expenditure. Dogs being calmer, using less energy per kilogram, like Labradors and Newfoundlands had a better longevity prospect than aggressive dogs such as Great Danes and Fox terriers. According to Careau, individuals who created these breeds were choosing dogs in respect to personality. They did not consider whether the dogs lived long or ate much. This is why Careau, believes that metabolic demands and personality are somehow associated genetically.
Franjo Weissing, a theortical biologist from University of Groningen in the Netherlands says that “It’s an intriguing finding”. He associated the finding to the philosophy to “live fast and to die Young”. Weissing, was a co-author of a significant paper in 2007 analysing relations of “how tradeoffs in life history between living speed and longevity can lead to the evolution of animal personality”. It is interesting to note that, this research is in-line with what is proclaimed by the natural selection models.
Nevertheless, everyone does not agree to the idea that longevity for dogs is related to the evolution in nature. Joseph Williams, physiologist, of Ohio State University in Columbus, consider that dogs are different in nature regarding longevity. For example, an Elephant survives for decades, whereas a mouse lives roughly only 7 to 9 months. However, a Saint Bernard is outlived by a small Chihuahua.
Source: Science Magazine
Mon, Jun 28, 2010
Anti Aging, Bioscience, Longevity