Showing posts with label General Information. Show all posts
Showing posts with label General Information. Show all posts

Saturday, September 12, 2020

Modern Dogs May Have Originated From Primitive Canids From Altai - Not From Wolves

A Deviation From Widely Known Information: Probably Primitive Wolves Are Not The Ancestors of Our Modern Dogs



The DNA analysis affirms that the Canidae from Altai was a primitive and one of the oldest ancestor of dogs. DNA was collected from a right lower lateral incisor and a mandibular bone fragment from the dog-like canid



Fact be revealed at the very outset! Clear and unambiguous phylogenetic reconstructions of the evolutionary process of today's dogs cannot be laid with perfection because incidences of hybridization within the genus Canis has disturbed the evolutionary flow to a great extent. This eventually lead to an unresolved trees. Hence, the perfect interpretation of branch support values on phylogenetic trees of the evolution of contemporary dogs may not possible. However, researchers have ascertained that today's dogs had very close relation with a dog-like canids from Altai, contrary to the popular belief that dogs have descended from Pleistocene wolves.



There has been a lot of controversies related to the origin of the modern domestic dogs. Findings from the advanced genetic research indicated that the modern dogs that we domesticate today have no relation with wolves of Late Pleistocene age. Some fossils of ancient creatures somewhat like dog were found even prior to the * Last Glacial Maximum. It was, thereafter globally accepted that the dog domestication had started even prior to agriculture about 10,000 years ago.



While evaluating the genetic relationship of one of the oldest dogs, the researchers have isolated ancient DNA from the recently described putative 33,000-year old dog of Pleistocene age from Altai. They analyzed 413 nucleotides of the mitochondrial control region, and came to a conclusion that the unique haplotype of the Altai dog is more closely related to our modern dogs than it is to contemporary wolves.



In the year 1975 Dr Nikolai D Ovodov conducted the first paleontological survey, when complete skull and mandibles of a dog-like creature were discovered. the fossile was found in a cave called Razboinichya in southern Siberia, Russia. The Razboinichya cave was discovered in the year 1962 in the northwestern zone of the Altai Mountains.



* Note: The Last Glacial Maximum (LGM) was the last period in the history of Earth's climate. This was a period when ice sheets were at their greatest extension and the period was approximately between 26,500 and 19,000–20,000 years ago. This was the peak of the last glacial period.



The discovery of a 33,000-year-old fossil tooth in southern Siberia opened up a new chapter about the age of dog-human relationship. This was the fossil of one of the oldest known ancestor of the dogs that we see today, said the researchers, who named the animal 'Altai Dog' - named after the mountain where the discovery was made. The study was made by a group of scientists led by Anna Druzhkova from the Institute of Molecular and Cellular Biology, Russian Federation.



According to the researchers 'Altai dogs' have been found to have more close resemblance with the contemporary dogs and prehistoric canidae found in the American continents than it has with the wolves. The finding shows that the dog-human relationship could be as old as around 33,000 years, which means human used to domesticate dog even 33,000 years ago.



The skull of a dog-like canid found in a cave in the Altai Mountains of southern Siberia

(Image: © Ovodov ND, Crockford SJ, Kuzmin YV, Higham TFG, Hodgins GWL, et al. (2011) A 33,000-Year-Old Incipient Dog from the Altai Mountains of Siberia: Evidence of the Earliest Domestication Disrupted by the Last Glacial Maximum. PLoS ONE 6(7): e22821. doi:10.137)


Documentations have shown that human and dogs had been buried together in Germany around 14,000 years ago. This has gone a long way to prove that dog-human relationship is quite old. However, advanced genetic studies have shown that the act of domesticating dogs was originated in China and the Middle East, as reported by LiveScience.



The study of Anna Druzhkova and the team was published Jyoti Madhusoodanan in the journal PLOS ONE in 6 March, 2013. The study was made by the critically analyzing of "DNA extracted right lower lateral incisor and a mandibular bone fragment" from the fossil of dog-like animal that used to live in southern Siberia. The genetic sequences of the the Altai specimen was compared with those of 72 modern dogs picked from 70 different canine breeds, 30 wolves, 4 coyotes and 35 prehistoric canid species from the Americas. The study on the new Siberian fossil revealed that it was one of the oldest known domestic dogs that was more related to the the dogs of today that the wolves.



The 'Altai Dog', as the researchers named it, used to be domesticated, which means the origin of the domestication of dogs would be pushed further back and the widely popular belief of domestic dogs evolving from the grey wolf has been seriously debated.



Scientists say, "Pleistocene wolves from the Razboinichya cave are not closely related to the specimen studied here.... more data of prehistoric wolves from the same region are needed to estimate the population diversity and obtain a more comprehensive picture of genetic relationships of Altai canids"



In 1975, the researchers excavated the skull of dog-like canid that existed on the Earth some 33,000 calender years ago. the excavation was carried out in Razboinichya Cave, located in the Altai Mountains of southern Siberia. Dr. N.D. Ovodov, co-author and member of Institute of Archaeology and Ethnography SB RAS, stated that the team had extracted DNA from a right lower lateral incisor and a mandibular bone fragment from the fossils of canid, by rigorously following the all stringent criteria of extraction that are mandatory to prove the authenticity of ancient DNA.


Outcome of the Research:

Dr N.D. Ovodov said, "We obtained mitochondrial DNA control region sequences from both the tooth and mandible of the 33,000 cy old putative dog specimen from Altai and found them to be identical. In order to evaluate the genetic relationship of the Altai specimen to any known dog/wolf specimen, we performed several analyses." Sir Ovodov said that the outcome of their research revealed 99% similarity (but no perfect match) to any dog that we know of today.



The team of scientists also took another step forward and compared the mitochondrial DNA control region sequences of the dog-like canid with those of the Pleistocene wolves from the Razboinichya cave. Dr. Ovodov said, "Pleistocene wolves from the Razboinichya cave are not closely related to the specimen studied here".



Reproduced from the articles written by:



Anna S. Druzhkova, Vladimir A. Trifonov, Nadezhda V. Vorobieva, Alexander S. Graphodatsky


Department of Genomic Diversity and Evolution, Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia



Olaf Thalmann



Division of Genetics and Physiology, Department of Biology, University of Turku, Turku, Finland



Jennifer A. Leonard



Conservation and Evolutionary Genetics Group, Estación Biológica de Doñana (Consejo Superior de Investigaciones Científicas), Seville, Spain



Nikolai D. Ovodov



Institute of Archaeology and Ethnography, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia



Robert K. Wayne



Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, United States of America




Click here to know more about the study.


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Monday, December 10, 2018

Feet and Front Types in Dogs

The types of dog fronts and dog feet vary largely from breed to breed. While certain types of dog fronts and dog feet types are desirable for certain dog breeds, they are fault for others. Fronts of dogs and dog feet influence their gait greatly, and in turn affect the working ability of the dog. The types of fronts and feet in dogs are critically judged in the show ring in order to filter out the quality from the sub standard ones. It is hugely important to notice the dog fronts and feet of dogs while you pick a puppy. It is very important to see the parents, the types of fronts and feet they have while picking a puppy. It is hence tremendously necessary to understand the different types of dog fronts along side the different dog feet types.

Different types of dog fronts 


Bowed front: The bowed fronts are those front types in dogs in which the legs tend to curve out from the elbows and then tend to tuck in towards the region of wrists. This type of fronts of dogs gives the dog bowed look while viewed from the front. Although this dog front type is a serious fault in most dog breeds, but this is considered desirable in a few breeds like Pekingese and Tibetan Spaniel dogs.


Crooked fronts: Crooked front, although may sound weird as a dog front type, is an essential construction of forequarters in certain short legged dog breeds like Dachshunds & Basset Hounds. Dog breeds like Dachshunds and Basset Hounds, who have very short legs have to accommodate the front part of the chest in the gap between their front legs. The Crooked legs give a distinctive look with the front legs inclined inwards, and slightly curved sometimes, when viewed from the front.

Gun-barrel front: The gun barrel front is the front type in dogs that have straight front when viewed from the front. In this dog front type both the forelegs and the pasterns are straight and positioned almost perpendicular to the ground and parallel to each other. This dog front type is found in breeds like Irish Wolf Hounds, Norwegian Buhund, Manchester Terriers etc.

Horse Shoe Front: This dog front type are often seen in certain breeds as standard, while faults in the others. The terminology “horse shoe fronts” are used to describe a front type where the forelegs are straight and are positioned wider apart at the chest than at the feet. Bedlington Terrier has this type of front.

Straight front: From the name itself it is clear that this dog front type is a front which is straight. Often considered as the alternative name for the gun barrel dog front type, the straight front type are found in dogs with straight forlegs, which are parallel and almost straight through out the wrist and pastern and are positioned vertically on the ground.

Wide front: Wide front type in dogs give a smart and balanced look when viewed from the front. By this term it is usually meant that the front is wider than it normally should be, but in certain dog breeds such as Bull Dogs, Istrian Short Haired Hound (Istrian Setter), American Staffordshire Terrier have this type of front.

Narrow front: The term “narrow front” is usually used to describe the front types in dogs that have fronts narrower than what the standards demand. This dog front type is normal and desirable in breeds with longer legs such as Whippet, Grey Hounds, African Azawakh. It is hereby to be noticed that dogs with this type front are usually fast runners.



Different types of dog feet

Cat feet: The term cat feet are used to define feet that are tightly compact and round in shape with the toes well arched and bunched together tightly or closely cupped. The two center toes in cat feet are just slightly elongated as compared the rests. The cat feet have well cushioned pads covered with thick layer of skins. Bulldog is an example of a dog breed that has cat feet that leave impressions round, rather than oval.

Hare feet: The hind feet of Borzoi is the best example of this feet type. Amongst all types of dog feet, Hare feet leave a comparatively longer impression, rather than round and oval ones. This type of dog feet has the center toes longer compared to the outer and inner toes. In hare feet type the toe arching is less marked, which makes the feet looks longer than any other types of dog feet.

Oval feet: Also called Spoon feet or Spoon-shaped feet, these types of dog feet are mostly found on Pointers. You may find it to be really confusing while distinguishing between an oval feet type and cat feet type. There’s a hair line difference between the two types of dog feet and that can be understood by minutely examining the center toes, which are comparatively elongated than that of the cat feet. This dog feet type is usually considered as normal canine foot, unless otherwise specified by the standard of any particular breed

Webbed feet: Breeds that are bred to retrieve things from the water have webbed feet. In this type of dog feet there are strong webbings between the toes. Some of the arctic dog breeds like the sledge dogs, who have to work in the snow have webbed feet. These types of dog feet help the dog swim faster. Newfoundland is the best example of a breed this dog feet type (webbed feet).

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