| operations |
| comment | | "parent_author":"",<br>"parent_permlink":"lifestyle",<br>"author":"tonymahfud",<br>"permlink":"stress-management-helped-wolves-become-dogs",<br>"title":"Stress Management Helped Wolves Become Dogs",<br>"body":"Genetic mutations related to the production of the stress hormone cortisol may have played a role in the process of canine domestication\n\n\n![image.png (https:\/\/cdn.steemitimages.com\/DQmXSDCRkHkiYC3hTpt5fYnUYQFjG7eyLY2VvnhNobcBGD4\/image.png)\n\n\n\n\nThe wolf relatives of modern-day dogs began the evolutionary process of becoming humans\u2019 best friends more than 10,<br>000 years ago. But despite more than a century of research,<br> scientists still do not know the full story of how and why dog domestication occurred in the first place. Now a new study published on Thursday in Scientific Reports reveals genetic changes that may have allowed ancient dogs to feel comfortable around humans by lowering the stress levels the animals experienced in our presence.\n\n\u201cThis is the first genetic demonstration that supports the hypothesis that mutations in the stress response system initiated canine domestication,<br>\u201d says the study\u2019s senior author Miho Nagasawa,<br> an animal scientist at Azabu University in Japan.\n\nNagasawa and her colleagues recruited the owners of 624 dogs to enroll their pets in a study consisting of two behavioral tasks. The researchers categorized the dogs into two groups. One consisted of breeds that are considered to be relatively closely related to wolves,<br> such as Akitas and Siberian huskies. The second was made up of other breeds that are more distantly related to their wild relatives.\n\nFor the first task,<br> the pooches had to rely on clues from the researchers\u2014such as the direction of their gaze or a pointed finger\u2014to determine which of the two bowls had a treat hidden under it. This task was meant to establish how well the dogs understood human communicative signals. And it built on past findings that even very young domesticated-dog puppies are better at understanding human signals than adult wolves raised by people. In the new study,<br> as would be expected,<br> the researchers found no differences in performance between the groups of ancient and more recent dog breeds.\n\nFor the second task,<br> the dogs were presented with an impossible challenge: opening an unopenable container to access the delicious-smelling food inside. The researchers measured how much time the frustrated canines spent gazing back at them for help\u2014another behavior that wolves are less adept at than dogs. In this part of the experiment,<br> the scientists did find a significant difference between the groups,<br> with the closer wolf relatives spending less time looking back at the human experimenters for help. The authors interpreted this as showing that the more recent dog breeds have a higher level of social attachment to humans.\n\nAfter the tasks,<br> the researchers analyzed four genes in their canine subjects to look for differences that might relate to their relationship with humans. Among other things,<br> the team\u2019s analysis included genes involved in producing oxytocin\u2014a hormone associated with social bonding\u2014and cortisol,<br> which is a key stress hormone. The scientists found mutations in a cortisol-producing gene that differed between the recent and ancient dog breed groups. This finding also reflects a previous study that revealed lower cortisol levels in foxes that were selectively bred to be less fearful and less aggressive toward humans.\n\nGiven the correlation between changes in the cortisol-producing gene and the more ancient dog group\u2019s lesser social-cognitive abilities,<br> the authors surmise that lower stress levels likely played a role in dog domestication. Being less wary around humans would be a necessary first step for an animal to begin developing the social-cognitive skills needed to better interact and communicate with us.\n\n\u201cAlthough it is not yet clear whether cortisol,<br> a marker of stress,<br> is actually lower in dogs than in wolves,<br> the fact that two genetic mutations were observed\u2014one of which is accompanied by changes in the production of intracellular cortisol\u2014may provide clues to how the canine tolerance and ability to adapt easily to human society was acquired,<br>\u201d Nagasawa says. She and her colleagues are now conducting follow-up research to check whether cortisol levels actually differ between the two breed groups.\n\nThe Scientific Reports study presents \u201cexciting new evidence that dogs\u2019 unusual ability to cooperate and communicate with us evolved as a result of natural selection favoring wolves who could approach and eventually show friendly behavior toward humans,<br>\u201d says Brian Hare,<br> a Duke University evolutionary anthropologist,<br> who was not involved in the study.\n\nBut Maria Lahtinen,<br> a visiting scholar at the Finnish Museum of Natural History,<br> who also was not involved in the research,<br> questions whether the new findings necessarily apply to ancient dogs. \u201cThe problem in this study is that they have used modern dogs to study the past,<br>\u201d she says. \u201cI would not take this study as an indication of anything from the past but as indicative of how modern dogs behave.\u201d\n\nTo get around this challenge,<br> Hare suggests that future investigations could focus on populations of other ancient dog breeds. For example,<br> if the gene identified in the new study did indeed play a significant role in enabling dogs to communicate with humans in a new way,<br> he says,<br> then \u201cit should be that dingoes and New Guinea singing dogs also show the same relationship between their use of human gestures and this genetic candidate.\u201d",<br>"json_metadata":" \"tags\":[\"lifestyle\",<br>\"money\",<br>\"mind\",<br>\"elonmusk\",<br>\"dogs\",<br>\"intresting\",<br>\"facts\",<br>\"photography\" ,<br>\"image\":[\"https:\/\/cdn.steemitimages.com\/DQmXSDCRkHkiYC3hTpt5fYnUYQFjG7eyLY2VvnhNobcBGD4\/image.png\" ,<br>\"app\":\"steemit\/0.2\",<br>\"format\":\"markdown\" " |
|