Post by Hatzegopteryx on Jun 6, 2014 19:18:51 GMT
Below is a extract from a book documenting Wolf and 19th and early 20th century domestic dog skull measurements.
While the book is a bit dated, some very interesting data is presented. The inclusion of dog breeds from 100-150 years ago may give us a snapshot of what dogs looked like back then and also may reflect more functional designs since selective breeding for form was less prevalent then.
Source: Scott and Fuller, Genetics and the Social Behavior of the Dog. 1965
Large Northern European Races of Wolf and Dogs Mostly from 1863 t0 1930
The extract below states most data comes from Wagner's 1930 study which comprised mostly northern european wolf and dog skulls from european museums dating back as far as 1863. Note the wolves may not all been mature animals, as wolves were heavily persecuted at this time, resulting in more immature animals in population. However, based on results below the measurements appear to come from a roughly even mix of male and female northern wolves which are full grown. Also, the dog sample may be predominantly male dogs since owners kept more male dogs during this era.
Wolves Have Longer and Heavier Lower Jaws Than Most Dogs
The extract below states wolves have longer lower jaws than any dog and thicker lower jaws than all but the largest breeds. Keep in mind a sample with a roughly even mix of male and female northern wolves would likely average 100 lbs or less compared to Saint Bernards perhaps weighing 150 lbs or more. Longer lower jaws would provide a wider gape for biting larger body parts and allow for quicker jaw closure and therefore more frequent bites. A thicker jaw would indicate a stronger bite and/or better ability to hold onto struggling prey since the lower jaw must withstand these forces.
Wolves Have Skulls as Wide as Much Larger Sain Bernards and Wider Skulls Than Other Breeds
The following extract summarizes results showing wolves have very large skulls and jaw muscles compared to domestic dogs:
Specific details are shown in charts below. The chart plots basal skull length, which is a few centimetres shorter than total skull length, against bi-zygomatic width. Note how only saint bernards had skulls as wide as wolves and other large breeds, such as great danes and newfoundlands, had smaller skulls. Also, the bulldog and bulldog-old type are listed as well. During this time period bulldogs, particularly "old type", were likley more functional being closer to their roots. I wonder if the "old type" bulldog at this time (1863-1930) was essentially a pit bull? Either way the "bulldogs" do have wider skulls than most other dogs.
You can also see several dog breeds have wider skulls at similar skull lengths than jackals, coyotes, and dingos. However, certain of these dog breeds may weigh more than the wild canids at similar skull lengths. Still, it's quite clear that wolves have broader skulls relative to dogs than some of the smaller wild canids. This dichotomy is likely due to following two reasons:
1) Jackals, coyotes, and dingo hunt big game less frequently than wolves (i.e. lower "BFQ" or bite force for body size)
2) Smaller dogs are paedomorphic and have relatively broader skulls similar to young wolves
That being said, these smaller canids do tend to have longer upper canines than smilar size domestic dogs.
Upper Jaw Breadth Yields Interesting Results
The data below plots upper jaw bredath at the carnassials (i.e. palate or snout width). Interestingly, the great dane and german shepherd score "off the charts" compared to wolves and other dogs. Theoretically, a wider snout allows greater ability to resist struggles from an animal being bitten at the expense of reducting bite pressure. Certain dogs do seem to have wider snouts than wolves. However, IMO wolves more than make up for this by having much larger incisors and likely incisors in more curved arrangements which increase gripping power. Therefore, wolves may be able to bite with more pressure given same jaw musculature without trading off gripping power.
That being said, I was surprised to see german shepherds and great danes having much wider snouts than saint bernards, newfoundlands, and bulldogs. Not sure if great danes and german shepherds were much different at this time or some measurement errors occurred. Would be interesting to look at modern breed data.
Wolves Have Much Larger Molar Teeth
The following chart plots molar teeth size vs basal skull length. Wolves have much larger molar teeth than all dogs. While molar teeth are not directly relevant to a fight, other teeth are and data at end of post is quite consistent with this.
Results are Consistent with Modern Studies
The study below is as follows:
Source: Nowak, North American Quarternary Canis
The study used a sample of medium to large dogs including a mastiff, great danes, newfoundlands, and irish wolfhounds:
"For a sample of domestic dogs, only those
skulls were selected which, while known to
be C. familiaris, were superficially nearest to
those of C. lupus or C. latrans in appearance.
The extremes of domestication represented
by broad-skulled dogs (as bulldogs), narrow-skulled dogs (as Russian wolfhounds), and
dogs having greatly reduced rostra (as pugs)
were avoided. Extremely small dogs, those
in which the skull was less than 150 millimeters in greatest length, also were not used. Specimens utilized for a sample of domestic dogs, only those
skulls were selected which, while known to
be C. familiaris, were superficially nearest to
those of C. lupus or C. latrans in appearance.
The extremes of domestication represented
by broad-skulled dogs (as bulldogs), narrow-skulled dogs (as Russian wolfhounds), and
dogs having greatly reduced rostra (as pugs)
were avoided. Extremely small dogs, those
in which the skull was less than 150 millimeters in greatest length, also were not used.
Specimens utilized For a sample of domestic dogs, only those
skulls were selected which, while known to
be C. familiaris, were superficially nearest to
those of C. lupus or C. latrans in appearance.
The extremes of domestication represented
by broad-skulled dogs (as bulldogs), narrow-skulled dogs (as Russian wolfhounds), and
dogs having greatly reduced rostra (as pugs)
were avoided. Extremely small dogs, those
in which the skull was less than 150 millimeters in greatest length, also were not used.
Specimens utilized in the sample included 1
Eskimo dog, 5 Irish wolfhounds, 3 German shepherds, 2 sheep dogs 2 Newfoundlands.
1 doberman pinscher, 1 greyhound, 1 great
Dane, 1 mastiff, 1 Irish setter, 1 beagle, 1
basset hound, and 30 dogs of unknown or
mixed breed (see appendix A, part 3). Of
these 50 specimens, only 11 males and 9 females had been previously identified as to
sex. For the reasons explained above, domestic dogs of male, female, and unknown
sex were combined into a single sample.
"
Many of same or similar measurements from Scott's study were taken for the entire sample of northern wolves, and largest and smallest of each measurement.
The third row under Canis familiaris and Canis lupus male represent largest individual measurents.
From looking at these, we can note the following:
"Column 1" - Total Skull Length
Largest male wolf: 29.3 cm
Largest dog: 28.5 cm
"Column 2" - Zygomatic width
Largest male wolf: 16.4 cm
Largest dog" 15.4 cm
"Column 5" = Maximum width of snout across rear most molars
Largest wolf: 9.4 cm
Largest dog: 8.55 cm
"Column 6" - Palate (snout) width at P1
Largest wolf: 3.91 cm
Largest dog: 4.23 cm
"Column 7" - Snout Width at Upper Canines
Largest wolf: 5.5 cm
Largest dog: 5.9 cm
"Column 13 - Width of C1 (i.e. anterio posterior width of upper canines)
Largest wolf: 1.72 cm
Largest dog: 1.40 cm
"Column 14" - Crown length of P4 (upper carnassial)
Largest wolf: 3.05 cm
A canid researcher (Dayan) has theorized that carnassials play an important role in holding prey in canids (in addition to helping increase speed of eating).
Largest dog 2.25 cm
While the book is a bit dated, some very interesting data is presented. The inclusion of dog breeds from 100-150 years ago may give us a snapshot of what dogs looked like back then and also may reflect more functional designs since selective breeding for form was less prevalent then.
Source: Scott and Fuller, Genetics and the Social Behavior of the Dog. 1965
Large Northern European Races of Wolf and Dogs Mostly from 1863 t0 1930
The extract below states most data comes from Wagner's 1930 study which comprised mostly northern european wolf and dog skulls from european museums dating back as far as 1863. Note the wolves may not all been mature animals, as wolves were heavily persecuted at this time, resulting in more immature animals in population. However, based on results below the measurements appear to come from a roughly even mix of male and female northern wolves which are full grown. Also, the dog sample may be predominantly male dogs since owners kept more male dogs during this era.
Wolves Have Longer and Heavier Lower Jaws Than Most Dogs
The extract below states wolves have longer lower jaws than any dog and thicker lower jaws than all but the largest breeds. Keep in mind a sample with a roughly even mix of male and female northern wolves would likely average 100 lbs or less compared to Saint Bernards perhaps weighing 150 lbs or more. Longer lower jaws would provide a wider gape for biting larger body parts and allow for quicker jaw closure and therefore more frequent bites. A thicker jaw would indicate a stronger bite and/or better ability to hold onto struggling prey since the lower jaw must withstand these forces.
Wolves Have Skulls as Wide as Much Larger Sain Bernards and Wider Skulls Than Other Breeds
The following extract summarizes results showing wolves have very large skulls and jaw muscles compared to domestic dogs:
Specific details are shown in charts below. The chart plots basal skull length, which is a few centimetres shorter than total skull length, against bi-zygomatic width. Note how only saint bernards had skulls as wide as wolves and other large breeds, such as great danes and newfoundlands, had smaller skulls. Also, the bulldog and bulldog-old type are listed as well. During this time period bulldogs, particularly "old type", were likley more functional being closer to their roots. I wonder if the "old type" bulldog at this time (1863-1930) was essentially a pit bull? Either way the "bulldogs" do have wider skulls than most other dogs.
You can also see several dog breeds have wider skulls at similar skull lengths than jackals, coyotes, and dingos. However, certain of these dog breeds may weigh more than the wild canids at similar skull lengths. Still, it's quite clear that wolves have broader skulls relative to dogs than some of the smaller wild canids. This dichotomy is likely due to following two reasons:
1) Jackals, coyotes, and dingo hunt big game less frequently than wolves (i.e. lower "BFQ" or bite force for body size)
2) Smaller dogs are paedomorphic and have relatively broader skulls similar to young wolves
That being said, these smaller canids do tend to have longer upper canines than smilar size domestic dogs.
Upper Jaw Breadth Yields Interesting Results
The data below plots upper jaw bredath at the carnassials (i.e. palate or snout width). Interestingly, the great dane and german shepherd score "off the charts" compared to wolves and other dogs. Theoretically, a wider snout allows greater ability to resist struggles from an animal being bitten at the expense of reducting bite pressure. Certain dogs do seem to have wider snouts than wolves. However, IMO wolves more than make up for this by having much larger incisors and likely incisors in more curved arrangements which increase gripping power. Therefore, wolves may be able to bite with more pressure given same jaw musculature without trading off gripping power.
That being said, I was surprised to see german shepherds and great danes having much wider snouts than saint bernards, newfoundlands, and bulldogs. Not sure if great danes and german shepherds were much different at this time or some measurement errors occurred. Would be interesting to look at modern breed data.
Wolves Have Much Larger Molar Teeth
The following chart plots molar teeth size vs basal skull length. Wolves have much larger molar teeth than all dogs. While molar teeth are not directly relevant to a fight, other teeth are and data at end of post is quite consistent with this.
Results are Consistent with Modern Studies
The study below is as follows:
Source: Nowak, North American Quarternary Canis
The study used a sample of medium to large dogs including a mastiff, great danes, newfoundlands, and irish wolfhounds:
"For a sample of domestic dogs, only those
skulls were selected which, while known to
be C. familiaris, were superficially nearest to
those of C. lupus or C. latrans in appearance.
The extremes of domestication represented
by broad-skulled dogs (as bulldogs), narrow-skulled dogs (as Russian wolfhounds), and
dogs having greatly reduced rostra (as pugs)
were avoided. Extremely small dogs, those
in which the skull was less than 150 millimeters in greatest length, also were not used. Specimens utilized for a sample of domestic dogs, only those
skulls were selected which, while known to
be C. familiaris, were superficially nearest to
those of C. lupus or C. latrans in appearance.
The extremes of domestication represented
by broad-skulled dogs (as bulldogs), narrow-skulled dogs (as Russian wolfhounds), and
dogs having greatly reduced rostra (as pugs)
were avoided. Extremely small dogs, those
in which the skull was less than 150 millimeters in greatest length, also were not used.
Specimens utilized For a sample of domestic dogs, only those
skulls were selected which, while known to
be C. familiaris, were superficially nearest to
those of C. lupus or C. latrans in appearance.
The extremes of domestication represented
by broad-skulled dogs (as bulldogs), narrow-skulled dogs (as Russian wolfhounds), and
dogs having greatly reduced rostra (as pugs)
were avoided. Extremely small dogs, those
in which the skull was less than 150 millimeters in greatest length, also were not used.
Specimens utilized in the sample included 1
Eskimo dog, 5 Irish wolfhounds, 3 German shepherds, 2 sheep dogs 2 Newfoundlands.
1 doberman pinscher, 1 greyhound, 1 great
Dane, 1 mastiff, 1 Irish setter, 1 beagle, 1
basset hound, and 30 dogs of unknown or
mixed breed (see appendix A, part 3). Of
these 50 specimens, only 11 males and 9 females had been previously identified as to
sex. For the reasons explained above, domestic dogs of male, female, and unknown
sex were combined into a single sample.
"
Many of same or similar measurements from Scott's study were taken for the entire sample of northern wolves, and largest and smallest of each measurement.
The third row under Canis familiaris and Canis lupus male represent largest individual measurents.
From looking at these, we can note the following:
"Column 1" - Total Skull Length
Largest male wolf: 29.3 cm
Largest dog: 28.5 cm
"Column 2" - Zygomatic width
Largest male wolf: 16.4 cm
Largest dog" 15.4 cm
"Column 5" = Maximum width of snout across rear most molars
Largest wolf: 9.4 cm
Largest dog: 8.55 cm
"Column 6" - Palate (snout) width at P1
Largest wolf: 3.91 cm
Largest dog: 4.23 cm
"Column 7" - Snout Width at Upper Canines
Largest wolf: 5.5 cm
Largest dog: 5.9 cm
"Column 13 - Width of C1 (i.e. anterio posterior width of upper canines)
Largest wolf: 1.72 cm
Largest dog: 1.40 cm
"Column 14" - Crown length of P4 (upper carnassial)
Largest wolf: 3.05 cm
A canid researcher (Dayan) has theorized that carnassials play an important role in holding prey in canids (in addition to helping increase speed of eating).
Largest dog 2.25 cm