0_Wizard
Researchers have compared dog mutations to genetic changes in humans that trigger reduced intelligence. Looking at my dog, I can believe that.
New research seems to show that dogs have mutations to equivalent genetic regions in humans where changes are known to trigger high sociability and somewhat reduced intelligence.
chosen_Dog_0
Dog
chosen_topic_0_Dog
Carcinogenesis
Carcinogenesis, also called oncogenesis or tumorigenesis, is the formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by changes at the cellular, genetic, and epigenetic levels and abnormal cell division. Cell division is a physiological process that occurs in almost all tissues and under a variety of circumstances. Normally the balance between proliferation and programmed cell death, in the form of apoptosis, is maintained to ensure the integrity of tissues and organs. According to the prevailing accepted theory of carcinogenesis, the somatic mutation theory, mutations in DNA and epimutations that lead to cancer disrupt these orderly processes by disrupting the programming regulating the processes, upsetting the normal balance between proliferation and cell death.
Dog
The domestic dog ("Canis lupus familiaris" or "Canis familiaris") is a member of the genus "Canis" (canines), which forms part of the wolf-like canids, and is the most widely abundant terrestrial carnivore. The dog and the extant gray wolf are sister taxa as modern wolves are not closely related to the wolves that were first domesticated, which implies that the direct ancestor of the dog is extinct. The dog was the first species to be domesticated and has been selectively bred over millennia for various behaviors, sensory capabilities, and physical attributes. Their long association with humans has led dogs to be uniquely attuned to human behavior and they are able to thrive on a starch-rich diet that would be inadequate for other canid species.
Origin of the domestic dog
The origin of the domestic dog is not clear. The domestic dog is a member of the genus "Canis", which forms part of the wolf-like canids, and is the most widely abundant terrestrial carnivore. The closest living relative of the dog is the extant gray wolf and there is no evidence of any other canine contributing to its genetic lineage. The dog and the extant gray wolf are sister taxa as modern wolves are not closely related to the wolves that were first domesticated. The archaeological record shows the first undisputed dog remains buried beside humans 14,700 years ago, with disputed remains occurring 36,000 years ago.
Evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. Evolutionary processes give rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms, and molecules. Repeated formation of new species (speciation), change within species (anagenesis), and loss of species (extinction) throughout the evolutionary history of life on Earth are demonstrated by shared sets of morphological and biochemical traits, including shared DNA sequences. These shared traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct a biological "tree of life" based on evolutionary relationships (phylogenetics), using both existing species and fossils.
Evolution of the wolf
The evolution of the wolf occurred over a geologic time scale of 800 thousand years, transforming the first Middle Pleistocene wolf specimen that is recognized as being morphologically similar to "Canis lupus" into today's dog, dingo and gray wolf. Ecological factors including habitat type, climate, prey specialization and predatory competition has greatly influenced the wolf's genetic population structure and cranio-dental plasticity. Wolves went through a population bottleneck 20,000 years before present (YBP), which indicates that many wolf populations had gone extinct at a time that coincided with the Last Glacial Maximum and the expansion of modern humans worldwide with their technology for capturing large game.
Domestication of animals
The domestication of animals is the mutual relationship between animals with the humans who have influence on their care and reproduction. Charles Darwin recognized the small number of traits that made domesticated species different from their wild ancestors. He was also the first to recognize the difference between conscious selective breeding in which humans directly select for desirable traits, and unconscious selection where traits evolve as a by-product of natural selection or from selection on other traits. There is a genetic difference between domestic and wild populations. There is also such a difference between the domestication traits that researchers believe to have been essential at the early stages of domestication, and the improvement traits that have appeared since the split between wild and domestic populations.
Introduction to evolution
Evolution is the process of change in all forms of life over generations, and evolutionary biology is the study of how evolution occurs. Biological populations evolve through genetic changes that correspond to changes in the organisms' observable traits. Genetic changes include mutations, which are caused by damage or replication errors in organisms' DNA. As the genetic variation of a population drifts randomly over generations, natural selection gradually leads traits to become more or less common based on the relative reproductive success of organisms with those traits. The age of the Earth is about 4.54 billion years.