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The Great Apes
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I love the really close-up camera shots ( post #75 ) where we can see little minute details of the animals.
From Dian Fossey Gorilla Fund blog, Cantsbee, last of Dian Fossey’s silverbacks, now presumed dead:
 *This image is copyright of its original author He was named “Cantsbee” by Dian Fossey upon his birth in 1978, since she believed his mother to be a male until she gave birth. Upon seeing the newborn, Fossey exclaimed “It can’t be,” which turned into the name Cantsbee. That day was Nov. 14, 1978, about a year after Fossey favorite gorilla – Digit – was killed by poachers. Since then, mountain gorilla Cantsbee went on to create a historic legacy in many ways, leading the largest group of gorillas ever observed, remaining dominant for the longest reign ever recorded, siring the most offspring, and passing the statistical life expectancy for mountain gorillas. On Oct. 10, 2016, Dian Fossey Gorilla Fund trackers reported that silverback Cantsbee was not in his group when they arrived for daily monitoring. Since he is elderly and the group had been traveling a lot, it was possible that he had been left behind, so the group’s trackers spent the next day looking for him or for his traces, but nothing was found. A succession of teams have since conducted extensive and wider searches and a big final search was conducted on Nov. 3, with seven teams composed of Fossey Fund trackers and Rwanda park authorities. However, no trace of Cantsbee has been found and staff are ready to conclude that he has died. On Nov. 14, he would have been 38 years old.  *This image is copyright of its original author A closely observed life Cantsbee took leadership of his group from the late silverback Pablo in 1995. His group is still called Pablo’s group today, but for the past year has been largely led by his son, Gicurasi. All other members of the group are being closely observed and exhibiting normal behavior, after some earlier subgrouping. After being followed since birth by Dian Fossey and succeeding staff of the Fossey Fund, stories about Cantsbee and his group are many. Along with being a strong leader, Cantsbee is known to many as an active and responsible father. For example, Fossey Fund President and CEO/Chief Scientific Officer, Tara Stoinski, Ph.D., remembers seeing Cantsbee “babysit” five or six infants at a time while their mothers were off foraging. “I think of Cantsbee as the most powerful and confident of all the silverback leaders,” says Veronica Vecellio, the Fossey Fund’s gorilla program manager in Rwanda, at the Karisoke Research Center. “I have bright memories of his group resting together, gathered around Cantsbee or following him by forming long lines, among the most surreal moments that I have experienced in the wild. “Cantsbee is definitely a piece of history that has now ended,” Vecellio adds. Indeed, there is now only one gorilla remaining from among those that Dian Fossey knew personally – the elderly female Poppy. Special strategies and personality Cantsbee actually maintained a multi-male group for many years, and this gives his group a good asset for the future, says Vecellio. “We hope the males will follow the father’s example and be cohesive in order to keep the group strong going forward. In any case, it will be a very interesting dynamic to observe.” Fossey Fund trackers and staff all remember Cantsbee as a peaceful and gentle, yet strong, intelligent and respected leader. “Cantsbee was a unifier and pacifier,” says Karisoke tracker Francois Xavier Ndungutse (“Conseiller”). “He was a nice leader who knew how to keep different and diverse individual gorillas together. He was also good in caring for orphans in the group and in fact he is the one who cared for his son, Gicurasi, when the mother was lost at early age. I worry about the group now, once they realize that he really is deceased.” “Cantsbee was a strong and respectable leader even during his old age,” adds tracker Jean Bosco Ntirenganya. “He was a leader who cared and protected the family and group, always leading them to find enough food as well as safety from other groups interacting. He could calm an intense situation among others in the group too, including strong aggressions.”  *This image is copyright of its original author Fifty years of protection pays off “The longevity and success of Cantsbee is credit to not only his own unique strengths, but also to the daily protection and monitoring provided by the Fossey Fund’s trackers,” says Dr. Stoinski. “At the time of Cantsbee’s birth, poaching was at some of its highest levels, which motivated Dian Fossey to start funding anti-poaching patrols. As a result of this increased protection, which we have maintained for decades, Cantsbee lived the longest and most successful life of any male gorilla ever observed. His legacy will continue for a very long time.” By the late 1970s, when Cantsbee was born, the mountain gorilla population had dwindled to 250 individuals and it was thought that they could be extinct by the year 2000. Today, almost 50 years since Dian Fossey began her vital research efforts in Rwanda, their numbers in the Virunga mountains have nearly doubled, to 480 individuals. The Fossey Fund is now also applying this successful conservation model to save a close cousin of the mountain gorillas, the Grauer’s gorilla, a critically endangered species found only in Democratic Republic of Congo and considered one of the 25 most endangered primates in the world."
Considering that most here hold the Big Cats like tigers and lions in the highest of regards, I wanted to make a point in this Silverback's case.
He first became dominant within his older brother's group in 1994. So that means he was the dominant male of his group for twenty two years. Let that number sink in for a moment. And one more thing. He has fathered a huge number of sons and daughters, I think the number is around thirty offpsrings, and that is even taking into consideration he always led multi-male groups, to make it more understandable, esentially the same as a coalition of lions. And yet, he was able to do this, to be such a successful male, surpassing most coalitions of lions or individual dominant tigers or other big cats.  (11-14-2016, 11:31 PM)Majingilane Wrote: Considering that most here hold the Big Cats like tigers and lions in the highest of regards, I wanted to make a point in this Silverback's case. Wouldn't that also speak to the lack of the species #'s in that region? I don't know enough of about gorilla social life to try and compare. Either way, it's an impressive run. (11-14-2016, 11:35 PM)Pckts Wrote: Wouldn't that also speak to the lack of the species #'s in that region? Well, yes and no. It's true in a sense, because there aren't many mountain gorillas, at least not in the species sense. However, during the last yeras those numbers have been in a steady rise, and now the opposite is happening. There are almost "too many" gorillas relatively to the small amount of space they have to live in, something that has led to many more deaths of dominant silverbacks in intergroups fights, or dominant silverbacks vs lone silverbacks. The situation is very similar to what is happening with tigers now, like it happened in Kanha, you know with territories filled with dominant males that eventually a death is going to happen. Quote:Either way, it's an impressive run. I agree completely. You know, for them it isn't that much different than for big cats. Not every silverback is fit enough for being the leader. Some males get to be leaders of a group to then finding themselves unable to hold on to that for more than a few months. All males have this drive to form a group, it's so wired into them that they will try until their last days, but most of them simply aren't able to get there. And for them, it's more than just about being good fighters. That's an important part, but it's not enough. A dominant silverback has to be able to look after his entire group, has to be able to led them to proper food sources and at the same time avoinding poachers. He also has to be able to deal with different groups, either trying to have the stamina, the charm and a proper show off base to attract females to his group, or the inverse, to be able to be "enough of a man", so to speak, to convince his females that he's the best they can get so that they don't ditch him off for a rival silverback. A dominant silverback has to be able to difuse tension between the group's members, and he has to do it often. Females are kind of bitches with each others and, naturally, the younger silverbacks also want a piece of the cake if they can get it (if you know what I mean...). And finally, children. A good sign of a good dominant silverback is how good of a father is he. Kids are drawn to him in a huge manner, and he has to be extremely patient with them and, should the mother of one die, or as it happens countless time, leave him for a rival, he has to care for that orfan kid, because the rest of the females in his group don't give a damn for that little one. This is just some of the things that make up what the social life of a silverback is, but it is much more complex than what it seems like, and just as fascinating as the lives of the predators.
I agree, so from the sounds of the first part, it's a two part answer.
1st: He was extremely fit and strong as a leader. Smart, courageous and imaginative, I'm sure. 2nd: He came at the right time, numbers were down and he was the right one to lead them and now their population is booming fast and new leaders will have a tough time of repeating that longevity with the constant competition not seen in years past.
Credits to Tim Flach - The Aspinall Foundation.
Silverback Djala does not skip Chest Day...  *This image is copyright of its original author
@Majingilane,
I like the muscular structure of gorillas (even though they have less muscle mass % than humans on average): they always look quite fit regardless of fat content. Their protein-filled herbivorous habits help with this too.
Another one of Silverback Djala. Credits to @timflachphotography.
 *This image is copyright of its original author
(11-15-2016, 08:15 AM)Polar Wrote: @Majingilane, Do you have data in regards to a gorilla having less muscle mass and more fat than a human. I'm not denying it; but it doesn't seem too logical. (11-14-2016, 11:31 PM)Majingilane Wrote: Considering that most here hold the Big Cats like tigers and lions in the highest of regards, I wanted to make a point in this Silverback's case. 22 years is a remarkable time for any dominant male to remain at the top for any species. I have read about various individual grizzlies to dominate their domain for such a similar length of time, but a grizzly does not defend a harem of females with their young. For a bear, a big cat, a gorilla, or any other male animal, 22 years as the dominant male is quite the remarkable achievement.
Credits to Gorilla Doctors.
Dr. Fred performed a Routine Health Check on the Nyakagezi group this week and has reported back that the group is doing well. Here are some photos he took during his visit. Infant Mutagamba feeding.  *This image is copyright of its original author Young silverback Rukundo  *This image is copyright of its original author Adult female Czizanye feeding on a bamboo shoot  *This image is copyright of its original author
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There are a few NCBI articles that explain the muscular differences between a gorilla male (37-40% muscle weight/total weight) and a normal, fit human male (40-43% muscle weight/total weight), but that doesn't mean that a gorilla has less muscle mass, only that it has less muscle mass relative to its weight. Not more fat either, since gorillas constantly eat dense vegetation (their digestive system is quite longer), and thus that digestive weight gets stuck inside them for a long time, thus accounting for a lot of the body mass. Not to mention the thick skin as well.
Body mass in lowland gorillas: a quantitative analysis.
Zihlman AL1, McFarland RK. Author information Abstract Body proportions and tissue composition (e.g., relative contributions of muscle, skin, bone, and adipose to total body mass) were determined through dissection of four adult captive lowland gorillas. The relative contribution of bone varies little among the four animals (10.2-13.4%) despite considerable range in body weights (99.5-211 kg). In tissue composition, three animals have on average 37.3% muscle relative to body mass. Maximum estimates of body fat range between 19.4-44%. Differences in age, sex, and life history events partially explain the observed variation in body proportions and tissue composition among the four animals. Although gorillas are considered extremely sexually dimorphic in body weight and canine size, differences in tissue are not as dramatic as body mass differences suggest. This study found sex differences mostly in the upper body; males have relatively heavier forelimbs, including heavier deltoid, trunk-binding, and deep back muscles compared to the younger female. The old, obese female had one half the muscle tissue of the other three animals (16% vs. 37.3%), and twice the body fat (44%); forelimbs and upper body musculature were relatively well-developed to compensate for the restricted hip-joint movement due to arthritis. Data on the variation in tissue composition and body proportions in gorillas provide a basis for comparison with other hominoids, including humans. For example, compared to highly dimorphic orangutans, gorillas have more muscle, less adipose tissue, lighter forelimbs and heavier hindlimbs. Such analyses complement studies of the skeleton and contribute to our understanding of human evolution and adaptation. Copyright 2000 Wiley-Liss, Inc. https://www.researchgate.net/publication...e_analysis Most importantly is muscle distribution Results "In this study, our interest is in the gorilla pattern of total body composition, i.e., the proportion of bone, muscle, fat, and other tissues relative to total body mass and their distribution in the body. For this reason, we do not report here on the weights of individ- ual bones and muscles. Skeletal data are the focus of another paper, and weights of individual muscles are considered in a fu- ture article that illustrates variation be- tween species, using individual muscle weights"  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author Bone distribution as % total body mass Captive vs Wild "It is likely that, on average, captive goril- las are heavier and fatter than free-ranging ones. Studies of human and nonhuman pri- mate populations show that access to a rich food source and decreased activity result in heavier mass and higher body fat. For ex- ample, monkeys who are provisioned or can obtain human food remains or crops are de- monstrably heavier (Mori, 1979; Strum, 1991; Altmann et al., 1993). Body fat is rarely measured, but Altmann et al. (1993) showed that baboons at Amboseli who ate human food and traveled less were dramat- ically fatter than their counterparts. Parallel evidence in humans based on di- rect measurement of body composition shows that Europeans from the 19th cen- tury were lighter in weight and had lower body fat than the 20th century sample, pre- sumably due to changes in diet and activity" (Clarys et al., 1999). "Orangutans. Like gorillas, orangutans show marked sexual dimorphism in body mass and linear measurements. In tissue composition, gorillas and orangutans are relatively comparable in amounts of bone and skin. The striking difference in the two species is in the relative proportions of mus- cle and body fat. Healthy gorillas in our sample have on average 37.3% muscle, which exceeds that of the female orangutan (27%) and that of the male (35%). In the “other” category of tissue, which includes body fat, organs, and the gastrointestinal tract, gorillas at 35.4% are lower than oran- gutans at 42.7%, suggesting a greater amount of body fat or a heavier gastrointes- tinal tract in orangutans. In body proportions, gorillas have lighter forelimbs than orangutans. In the hind- limbs, female and male gorillas are compa- rable (17.5% of total body mass vs. 17.3%), whereas the female and male orangutan dif- fer markedly from each other in their hind- limb proportions (17.8% vs. 12.0%). These comparisons suggest correlations between the different behavioral ecology of the two species. Lowland gorillas consume foliage, fruit, and insects, feed and sleep in trees or on the ground, and travel exclu- sively on the ground (Tutin et al., 1991; Remis, 1997a). They live in relatively cohe- sive groups, usually with several adult males, adult females, and young (Tutin, 1996; Remis, 1997b). Although there are dif- erences in foraging and locomotion in fe- male and male gorillas, they do not appear to be marked. Orangutans, in contrast, are highly arbo- real and eat fruit, and adults are relatively solitary while foraging (Galdikas, 1984, 1985, 1988). Females and males differ in their arboreal travel, diet and foraging, so- cial interactions, and caretaking of offspring (Sujardito, 1982; Cant, 1987). Relative pro- portions of muscle or body fat probably re- late to a balance between locomotion and the ability to store fat." VS Homo sapiens "Homo sapiens. Clarys et al. (1999) sum- marized the available data on direct mea- surement of tissue composition based on 51 individuals (20 females, 31 males) compiled over a 150-year period. The individuals had known body weights, and absolute weights recorded for skin, muscle, bone, and adipose tissue. The subjects ranged in age from 16 –94 years; the average age for men was 56.6 years (SD 21.5), and for women, 75.5 years (SD 15.4). Body weights ranged from 38.5–97.2 kg in men, and from 32–75.4 kg in women. Muscle relative to body weight av- eraged 39.4% (SD 5.4%) in men; in women, 28.8% (SD 6%). Adipose tissue averaged 19.4% in men and 35.3% in women. For men, the standard deviation was 9.6%, and in women, 11.8%. The older age of the fe- male subjects probably contributed to the higher amount of adipose tissue, and lower muscle mass. The data on gorillas, orangutans, and hu- mans suggest that hominoids have the abil- ity to accumulate body mass, of which a significant proportion is fat. Further analy- sis of body composition in hominoids can refine the species comparisons and so more fully connect body composition and distribu- tion to adaptation and evolutionary history." |
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