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Post by arctozilla on Mar 10, 2024 10:57:35 GMT -5
That's because polar bears are more active hunters than brown bears due to being more hyper-carnivorous.
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Post by oldindigosilverback on Mar 16, 2024 3:18:14 GMT -5
That's because polar bears are more active hunters than brown bears due to being more hyper-carnivorous. Actually being a better hunter doesn't mean stronger. Polar bears have traded off speed for strength compared to brown bears mainly because of their decent weight advantage. The only time polar bears are faster is when the brown bear is in winter weight mode. I do think the brown bear is the stronger one pound to pound depending if their weights overlap as we do not want to neglect the square cube law.
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Post by arctozilla on Mar 16, 2024 3:39:57 GMT -5
Cats do have inferior strength to bears pound for pound. They mostly train lower body while bears mostly the upper body.
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Post by oldindigosilverback on Mar 17, 2024 2:37:14 GMT -5
Cats do have inferior strength to bears pound for pound. They mostly train lower body while bears mostly the upper body. Polar bears have 2/3 white fibre muscles on their chest and probably the brown bear too since the yellowish white bears owe their existence to the letter. Therefore, at least the brown bears and polar bears have more upperbody strength than big cats in my opinion. However, I believe big cats have their white fibre muscles distributed overall, which makes them more explosive locomotively.
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Post by oldindigosilverback on Apr 17, 2024 8:30:16 GMT -5
Two interesting quotes from the same link: manoa.hawaii.edu/exploringourfluidearth/biological/mammals/adaptationsCheck out the link for more info. I have already posted a link somewhere on this thread saying captive polar bears actually have more fatty adipose tissue compared to their wild counterparts. Polar bears do not seem to have true blubber although many articles call their fat blubber which actually helps them to float.
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Post by oldindigosilverback on Apr 17, 2024 8:31:34 GMT -5
It seems polar bears do not have true blubber. Many articles consider their fat to be blubber.
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Post by Gorilla king on Apr 17, 2024 21:39:16 GMT -5
It seems polar bears do not have true blubber. Many articles consider their fat to be blubber. Yes, this is very confusing, i have been researching and i really cant find the difference between "true blubber" and the blubber that polar bears have.
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Post by oldindigosilverback on Apr 19, 2024 22:29:17 GMT -5
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Post by oldindigosilverback on Apr 19, 2024 22:30:12 GMT -5
To be honest it is good to have people challenge your views as it can drive you to look for info until you find something new .
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Post by Gorilla king on Apr 20, 2024 5:37:53 GMT -5
So polar bears dont really have blubber, they have non specialized adipose tissue.
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Post by oldindigosilverback on Apr 20, 2024 6:28:17 GMT -5
/\ In addition captive polar bears have more fatty adipose tissue.
Due to having high metabolic rate, they lose their fat quickly.
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Post by oldindigosilverback on Apr 20, 2024 6:29:55 GMT -5
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Post by oldindigosilverback on Apr 20, 2024 6:41:35 GMT -5
Female Polar Bears Are Truly The Queens Of The Arctic.March 06, 2020 We have noticed the epithet often given to polar bears, “Kings of the Arctic” is unfair and doesn’t do justice to the most important figure in the Arctic, the mother polar bear. When we think of the sacrifices that mother polar bears endure and the role they play in preparing the next generation of polar bears, it is clear why female polar bears are truly “Queens of the Arctic.” What They Endure.
When we consider that for polar bears the winter is their most successful hunting season, where they build up the body mass to last through the slower seasons, it is remarkable the sacrifice mother polar bears experience by giving birth through this season. When they emerge from their maternity dens it is often the end of the frozen season and the beginning of a long season where a lack of sea-ice as a hunting platform makes it significantly harder to hunt and most polar bears tend to fast through the warmer months. Although polar bears mate during the spring season when they’re out on the frozen sea-ice, mother polar bears don’t actually become fully pregnant until the autumn. They undergo something called “delayed implantation”. This means that the initial fertilized egg stops growing for the next 4 months. This allows the mother to build up the energy stores and fat content to physically last the long winter without hunting and has the energy to nurse the cub once it is born. Then, after 4 months the egg implants in the uterine wall and continues to develop for another 4 months. This “delayed implantation” ensures that the mother has the best chance of giving birth and supporting a cub(s) and is in the physical condition to then raise the cub. This sacrifice of body and time is a lot to endure. A pregnant polar bear must gain at least 200 kg (441 lb) to build up the fat reserves for cubbing, or else the egg is absorbed and does not fully gestate. With this mass gain, a mother polar bear can weigh as much as 500 kg (1,102 lb) which is twice their regular weight. This weight gain becomes vital because the mother will dig their maternity den between October and November and won’t emerge until March or April, having not eaten anything at all the whole time. Cubs are born between November and January and the mother will begin nursing a cub up to six times a day for the first four months. The average fat content of polar bear milk is 33%, which is much higher than a human with 3-5% fat content. This is aimed at quick development and weight gain for the polar bear cubs. A cub is born weighing roughly one pound and when they leave the den they weigh as much as 22-33 lb. Consider the effects this has on a nursing mother. Mothers tend to give birth to twins but sometimes will have one cub and even more rarely three. The cubs will nurse from the mother for the following 18 to 30 months. Some will ween off nursing after 18 months but still stay with their mother for a total of 2 to 3 years as they learn to hunt and tricks to surviving in the Arctic landscape. As soon as the new family emerges from their maternity den they will start the walk from their inland sanctity to the coast, often up to 16 km (10 mi) away, to begin hunting and a chance for the mother to have her first meal. Training The Next Generation.
It’s an obvious statement to say there wouldn’t be a next generation of polar bears without females bears since male bears still play a part in impregnating a partner, but that is where the duties of the male bears stop. It is the mother that will give birth and raise the cubs. Her sole focus is entirely on the development of the cub, going four to eight months without food or drink while they are in a den dug into snow or peat soil just a little bit larger than the mother herself. The den is aimed at providing a secluded and temperate environment for the fragile newborn cubs. Their baby fur is very fine and provides little insulation yet, and the cub is blind at first. When they emerge from the maternity den between March and April, the mother and cub will remain near the den for about 12 more days. This allows the cub to start to acclimatize to the colder weather outside and develop their walking muscles near the protection of the den. The mother will then lead the cubs towards the sea ice to begin hunting again. This walk to the sea is often slow and full of distractions as the cub plays in the snow and gets used to walking on ice. Mothers will often carry cubs on their back through deep snow and over water because their fur and fat insulations have not developed to keep the fragile cubs warm. Cubs will often start eating solid food as soon as the mother makes her first kill, along with nursing from the mother. The cubs will spend the first year mostly watching their mother hunt and learning the techniques for catching seal. The cub may start trying to hunt within the first year but is very rarely successful until their second year. They are still a little clumsy and don’t understand the need for patience. Tricks their mother will teach them can be waiting at a seal’s breathing hole waiting patiently for it to appear or sneaking along its belly or tiptoeing in the effort to prevent any vibrations on the ice that might warn the seal of a coming polar bear.
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Post by oldindigosilverback on Apr 20, 2024 6:43:51 GMT -5
By the time a cub is two years old, they spend about 7% of their time hunting and may only catch a seal every five to six days. Seal is their primary diet because it is the only food source with a high enough fat content and calories to keep a polar bear healthy in a landscape with few resources.
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Post by oldindigosilverback on Apr 20, 2024 6:49:00 GMT -5
At Arctic Kingdom
We are constantly amazed by the strength of mother polar bears and the caring attention they give their cubs. We often see cubs crawling all over the mothers back when they take a break. The patience a mother demonstrates when it is sneaking up on a seal and their cub starts to jump or growl, giving away the mother’s hard work. The lengths they go to in protecting the cub from the elements and challenges in the Arctic. To see the sensitivity of a mother cleaning a cub or the bravado of a cub trying to roar up at its mother is one of the most exceptional moments. There is a reason we return to these polar destinations and there is a reason our Expedition Leaders and Inuit guides have such a passion for polar bears. They are a statement of resilience in the face of a harsh climate but delicate and loving for the world’s apex predator. It can not be understated the role and the demands a mother polar bear faces when it gives birth to new cubs. They are solely responsible for developing the next generation and it is their own remarkable knowledge of the Arctic that allows them to pass on their skills to succeed. We, at Arctic Kingdom, give thanks to the mother polar bear and by providing safe viewing opportunities with the goal of making Arctic Ambassadors of our guests that visit the realm of the polar bear. We believe that this connection will encourage the protection of these beautiful animals. Seeing a polar bear in its natural environment makes their challenges real but also allows you to experience the tenderness of a mother polar bear to its cub and reminds us that caring for all animals makes the world a better place. Therefore, on this International Women’s Day we wanted to spend some time detailing the role of the mother polar bear but also to thank all the women in our lives. resources.arctickingdom.com/female-polar-bears-are-truly-the-queens-of-the-arcticFor more info, click the link above.
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Post by oldindigosilverback on Apr 20, 2024 6:57:11 GMT -5
Reply 13 " We estimated that 31% of the mass of storage is composed of muscles while 44% of the mass of structure is composed of muscle. Given the added pressure climate change has imposed on polar bear energy acquisition and use, our estimates highlight the role of muscles in long-term energy stores."So the mass storage is 31% muscles and the mass structure is 44% muscles. No specifics on white and red fibre muscle tissue sadly . 2/3 of polar bear's upper body consist of white fibre muscle.
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Post by oldindigosilverback on Apr 20, 2024 7:08:30 GMT -5
Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer.Associated Data.
Polar bears experience skeletal muscle atrophy during winter whether they hibernate or not. Bears spending summer on sea ice in the Arctic basin undergo a second period of atrophy caused by fasting, whereas bears with shore access to adequate, alternative food do not. Summer atrophy may influence fitness. Abstract.
When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April–May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these ‘shore’ bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These ‘ice’ bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt. www.ncbi.nlm.nih.gov/pmc/articles/PMC5550809/
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Post by oldindigosilverback on Apr 28, 2024 4:41:50 GMT -5
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Post by oldindigosilverback on Apr 28, 2024 4:42:39 GMT -5
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Post by oldindigosilverback on Apr 28, 2024 4:48:07 GMT -5
Polar Bear Anatomy: Explore Fascinating Details Now! The polar bear anatomy is a perfect result of millions of years of evolutionary refinement, optimizing these magnificent creatures for survival amidst the harsh Arctic conditions. The building block of a polar bear’s anatomy lies in its bulky body structure, which significantly contributes to conserving heat. The polar bear’s body is designed to maintain warmth. With extended torso and shorter legs, polar bears are capable of trapping as much heat as possible which is invaluable in their icy environment. Male polar bears, known as boars, can grow to an impressive size ranging from 350 to more than 700 kilograms, whereas females, sows, are usually half the size of their male counterparts. This large size enables them to retain body heat effectively. Equally essential in the polar bear anatomy are their large feet, crucial for both swimming and walking through deep snow. Measuring more than 30 centimeters in width, their wide, webbed paws provide a better grip and distribute weight more effectively over soft snow and thin ice. The considerable surface of the feet aids in propulsion while swimming, making them efficient and fast swimmers. Their bulky body structure and large paws provide them excellent insulation and movement capabilities, demonstrating the precise adaptive alignment of the polar bear anatomy with the challenging Arctic environment. Having learned about the remarkable adaptations of the polar bear, why not expand your understanding of these fantastic creatures? Uncover another surprising fact in the following exploration: “Are Polar Bears Left Handed? Discover the Truth Now!”). Thick Layers of Fat and Fur: The Insulation System.The harsh Arctic environment hosts a remarkable species – the Polar Bear. With significant physical attributes, the polar bear anatomy is honed perfectly to withstand and even thrive in the intense cold. One of the crucial components of this survival anatomy is the polar bear’s insulating fat layer and fur. Polar Bears are fitted with a dense, two-layered coat that functions as a crucial insulation system. The outer fur is thick and lubricated, repelling water and preventing it from reaching the skin. The underfur, situated beneath the outer layer, is shorter, denser, and works efficiently as an additional layer of heat insulation. The color of the fur, a common misconception, is not actually white. Rather, it appears so due to the way the fur reflects light. This optical illusion further aids their survival by providing a natural camouflage in their snow-white habitat. Underneath this fur is another layer – a thick layer of fat, typically more than four inches thick. This blubber is another aspect of polar bear anatomy that is vital to their survival in the hostile Arctic. The fat reserves, apart from serving as an excellent insulator, are also an energy store for times when food is scarce. The blubber layer contributes significantly to the polar bear’s buoyancy in water, aiding them in their long-distance, sustained swimming endeavors. These anatomical prerogatives, working in concert, enable the polar bears to conserve body heat efficiently, enduring the Arctic’s freezing temperatures, and the icy waters they often traverse. Thus, the anatomy of polar bear – from its two-layered fur to its fat deposits – showcases a fascinating range of adaptations developed for survival in one of Earth’s most punishing environments. Having explored the ingenious adaptability of the polar bear, consider further delving into the wildlife of the Arctic region by uncovering the mysteries surrounding those which prey on polar bears.
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