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Bear and bigcats anatomy
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Type II Muscle Fiber
EDIT SHARE Type II muscle fiber is also known as fast twitch muscle fiber. Muscle fiber types can be broken down into two main types: slow twitch (Type I) muscle fibers and fast twitch (Type II) muscle fibers.[1] These fast twitch fibers can be further categorized into Type IIa and Type IIb fibers,[1] which are also known as "fast twitch oxidative" and "fast twitch glycolytic," respectively. Type I fibers are characterized by low force/power/speed production and high endurance, Type IIB fibers are characterized by high force/power/speed production and low endurance, while Type IIA fall in between the two.[2] It is possible that a fiber might be transformed from Type IIB to Type IIAB to Type IIA with exercise training.[3]Furthermore, researchers at Boston University School of Medicine have found that increasing the mass or size of type II muscle fibers will lead to a significant decrease in fat mass or the amount of fat in the body.[4] A new study in the February issue of Cell Metabolism suggests that in regards to weight loss, lifting weights may be just as important as running on the treadmill.[5] Contents [show] Type IIA Fibers Type IIA fibers, or fast oxidative fibers, are used more during sustained power activities such as sprinting 400 meters or doing repeated lifts with a weight below maximum (but not with very light weights).[6] They contain very large amounts of myoglobin, very many mitochondria and very many blood capillaries. Type II A fibers are red, unlike Type II B fibers, which are white. Type IIA fibers have a very high capacity for generating ATP by oxidative metabolic processes, and split ATP at a very rapid rate. They have a fast contraction velocity and are more resistant to fatigue than Type IIB. [7] Type IIB Fibers Type IIb fast-twitch fibers, or fast glycolytic fibres (also known as Type IIx), are recruited for very short-duration high-intensity bursts of power such as maximal and near-maximal lifts and short sprints.[6] Type IIB fibres contain a low content of myoglobin, relatively few mitochondria, relatively few blood capillaries and large amounts glycogen. Type II B fibres are white, while Type I (slow twitch) fibers are red. Type IIB fibers are geared to generate ATP by anaerobic metabolic processes, however, they are not able to supply skeletal muscle fibres continuously with sufficient ATP, and fatigue easily. ATP at a fast rate and have a fast contraction velocity. Such fibres are found in large numbers in the muscles of the arms. [7] http://athletics.wikia.com/wiki/Type_II_Muscle_Fiber  *This image is copyright of its original author https://www.researchgate.net/publication...7/download  *This image is copyright of its original author  *This image is copyright of its original author https://www.sciencedirect.com/topics/bio...ology/myh6
Liger skull
Credit to @oddarticulations  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author
 (09-24-2018, 01:12 AM)epaiva Wrote: Liger skull Super massive, I guess the skull should weigh about 9 pounds after being cleaned up and dried. @peter does liger have proportionally denser skull than its parents?   (09-24-2018, 02:29 AM)GrizzlyClaws Wrote:(09-24-2018, 01:12 AM)epaiva Wrote: Liger skull I've seen ligers and tigons. Ligers often are larger and more robust than tigons. In many cases, lion features dominate. In the skulls I saw, things are a bit different. In most cases, the mandibula was lionlike (convex). The 'snout', however, was more tigerlike (relatively short and a bit vaulted). Same for the canines (large). The rostrum, however, often was lionlike (straight). Not one of the skulls I saw was exceptional in size and most were not as dense (heavy) as similar-sized skulls of wild lions and tigers. A few months ago, I found a book on the internet. Although published a long time ago, it was an interesting read. One of the chapters, written by a zoologist, has a lengthy description of a liger skull. I'll post it when I have more time. The heaviest skulls I saw were just over 5 pounds (2,268 kg.). Skulls of wild big cats often are relatively heavier than skulls of big cats born and raised in captivity. An exceptional skull of a wild lion or tiger might exceed 6 pounds, maybe 7. I've never measured a skull of exceptional size, but I do know that large skulls of wild big cats often are relatively heavier than average-sized skulls. Ligers are known for their size. Some males exceed 10 feet straight and 700 pounds. Although the relation between skull-size and weight is rather weak in big cats, it is to be expected that some exceptional individuals will produce an exceptional skull. The skull discussed is very large in all respects. The exceptional width no doubt is a result of captivity.  (09-24-2018, 01:12 AM)epaiva Wrote: Liger skull This liger skull is actually a little bit wider than the largest skull of Panthera atrox which is at 304 mm or approximately 12". Pretty impressive. I think an exceptional captive lion skull or tiger skull can reach that width too because the length of this liger skull is comparable to some male lion or tiger skull.
In my opinion, females acts as carriers for their fathers genes. So a tigress carries their fathers genes onto her offspring. That is the reason why ligers canine and skull are robust like that of a tiger.
I read this article and asked the concerned authority about the skeleton, they replied me it was brown bear. It is always great to get details from experts.
https://www.telegraph.co.uk/news/uknews/...-cave.html  *This image is copyright of its original author
The presence of ridge on the skulls may indicate the brown bears dominance in pleistocene in respective regions. Where as for polar bear there does not seem to have competition from other carnivores where as brownbears encountered big cats in their regions.
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