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The Great Apes
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Nice close up of a silverback mountain gorilla.
 *This image is copyright of its original author Doesn't he just remind you of a massive man but with a beard? 
Female gorillas recognize and respond to contagious disease
Lara Streiff 5 days ago  *This image is copyright of its original author  *This image is copyright of its original author A yaws-infected adult gorilla with red lesions mainly located on its face. Photo by Céline Genton/Université de Rennes 1 Salt clearings deep in the Congo basin host numerous breeding groups of Western lowland gorillas (Gorilla gorilla gorilla). These intelligent social mammals usually reside in groups of two to eight females defended by a single silverback male. Now, long-term studies of these populations show that female gorillas can identify a disfiguring disease in one another, and they consciously avoid it through informed social dispersal to other groups. A team led by Nelly Ménard of the ECOBIO laboratory at CNRS/University of Rennes 1 used a decade of observations to conclude that gorillas recognize a contagious skin infection called yaws in other individuals. Female members of a breeding group take the disease into account when deciding whether to migrate to another group. The findings, published recently in Ecology, suggest that females are more likely to change groups when the red facial lesions caused by yaws are visible either in the silverback or among multiple females in their breeding group. They also avoid joining groups with a high prevalence of the disease.  *This image is copyright of its original author *This image is copyright of its original author Odzala-Kokua National Park in the Republic of Congo. Photo by A. Lavandier/CNRS-University of Rennes 1When Ménard first visited the Odzala-Kokoua National Park in the Republic of the Congo nearly 20 years ago, she recognized that the frequent visits by gorilla social groups provided access to exceptional data on the demographic structure of their populations – as well as their dispersal patterns. During their years in the field, her team identified 593 individuals, divided into 59 breeding groups and 50 unmated units, clustered within two distinct populations of gorillas. Females move between breeding groups several times during their lifespan. The researchers recorded dozens of instances when females left their own groups or joined new ones. Both of the studied populations live in the same dense tropical forest with overlapping home ranges, so habitat was not a factor in the females’ decisions to change groups. In all cases where both the old and new groups were known, females moved to new groups with fewer numbers of severely infected gorillas. A female was more likely to leave her breeding group when there were more severely diseased individuals, when her breeding group was older, or when the male silverback was infected, the team’s observations showed. “We suspected that females were able to take the disease risk into account in their decision to leave or to join a group,” said Ménard. These perceptive apes most likely associate the visual cues of red facial lesions with the worsening effects of the disease, like deformities and handicaps, she said.  *This image is copyright of its original author *This image is copyright of its original author This infant was likely contaminated through contact with its mother. Photo by Peggy Motsch and Guillaume Le Flohic/CNRS-University of Rennes 1 *This image is copyright of its original author *This image is copyright of its original author Close contact with its mother may have led to the infection of this infant at a young age. Photo by Peggy Motsch and Guillaume Le Flohic/CNRS-University of Rennes 1Other studies have shown that spiny lobster, ants, mosquitofish, and house mice avoid others of their species who are visibly sick, said Dieter Lukas, a senior researcher at the Max Planck Institute for Evolutionary Biology in Plön, Germany, who was not involved in the study. Among primates, mandrills (Mandrillus sphinx) will avoid grooming others who are infected with endoparasites. However, the finding by Ménard’s team appears to be the first case of social mammals “choosing which group to join according to the disease status of the other group members,” Lukas said. There is still a social toll when females leave familiar breeding groups, such as lower status in new groups or delayed mating opportunities. Females also hesitate to migrate if they have an unweaned infant, fearing infanticide. The animals weigh these risks, Lukas noted: “The interesting observation is that female gorillas might be willing to pay a short-term cost… in order to potentially avoid a long-term cost associated with contracting a disease.” Ménard is curious whether other primates, such as chimpanzees (Pan troglodytes), show similar behaviors. “The few [chimpanzees] who visited the study clearings did not show any signs of this disease,” she said. However, a chimpanzee population being studied in Uganda displays facial deformities due to ingesting pesticides, offering a research opportunity: “It would be very interesting to test whether these [deformities] impact social relationships.”  *This image is copyright of its original author *This image is copyright of its original author A yaws-infected adult gorilla with red lesions mainly located on its face. Photo by Céline Genton/Université de Rennes 1https://news.mongabay.com/2019/11/female-gorillas-recognize-and-respond-to-contagious-disease/amp/?__twitter_impression=true
Citation: Baudouin, A., Gatti, S., Levréro, F., Genton, C., Cristescu, R. H., Billy, V., … Ménard, N. (2019). Disease avoidance, and breeding group age and size condition the dispersal patterns of western lowland gorilla females. Ecology, 100(9). https://doi.org/10.1002/ecy.2786 (10-01-2019, 08:18 PM)GuateGojira Wrote: Check the image of the record gorilla (based on weight):@GuateGojira @Shadow Now that you guys have seen my comparisons, I hope they made things clearer. I've concluded based on the comparisons with M'bongo and Samson, Guhonda would likely be over 570+ to 580+lbs (or over 259 to over 263kg). The other males (similar to Guhonda) would likely be over 550+ to 560+lbs (or over 250 to over 254kg). I'm normally not a fan of estimations, but I do have confidence in them when we include comparisons. Anyway, I just wanted to say what I didn't get to say before, but I hope everything is clearer now.  (12-01-2019, 03:51 PM)The Panther Wrote:(10-01-2019, 08:18 PM)GuateGojira Wrote: Check the image of the record gorilla (based on weight):@GuateGojira @Shadow I think, that it´s clear. We have for all animals confirmed weights and then some unconfirmed or estimations. Nothing wrong in discussing about these things, when keeping it clear when talking about confirmed cases and unconfirmed or what is estimated to be possible. I hope, that one day scientists would be able to get weighed one really big one again if some good reason like medical treatment would offer such possibility. Otherwise I hope, that people let gorillas live in peace and mind their own business. (12-01-2019, 04:12 PM)Shadow Wrote:@Shadow(12-01-2019, 03:51 PM)The Panther Wrote:(10-01-2019, 08:18 PM)GuateGojira Wrote: Check the image of the record gorilla (based on weight):@GuateGojira @Shadow Ok then. It's a good thing i had gorillas to compare Guhonda with, otherwise this would've been pretty difficult, but at least we are able to see their size range thanks to this. I'm pretty satisfied with my estimations here, do they look alright to you too? (12-01-2019, 04:47 PM)The Panther Wrote:(12-01-2019, 04:12 PM)Shadow Wrote:@Shadow(12-01-2019, 03:51 PM)The Panther Wrote:(10-01-2019, 08:18 PM)GuateGojira Wrote: Check the image of the record gorilla (based on weight):@GuateGojira @Shadow What you estimate seems to me quite possible. We know from captivity, that some gorillas have been much more. And some gorillas in wild live in excellent conditions with a lot of food too. So some older gorilla getting some extra weight, I don´t see any reason why not. 
Pictures and video from a chimpanzees sanctuary in Sierra Leone:
" Chimpanzees often embrace to provide a sense of comfort to one another and to support social bonds. They are a highly social species and need socialisation with each other in order to be healthy and happy! Pictured hugging is Fifo (left) and Ceasar. " :
I believe this photo has already been posted, but since you spoke about huge gorillas:
" Meet Isabukuru, a protected Gorilla in Rwanda. Behind him is Veronica, @savinggorillas Gorilla Program Senior Advisor. "
Huge dominant silverback and his group. Bwindi Impenetrable national park, Uganda.
 *This image is copyright of its original author
(11-25-2019, 12:44 PM)johnny rex Wrote:@johnny rex(11-25-2019, 05:36 AM)The Panther Wrote:(11-09-2019, 12:56 PM)johnny rex Wrote:@johnny rex(11-08-2019, 03:02 PM)The Panther Wrote: Samson the gorilla. He's one of if not the heaviest gorilla on record, he weighed in at 652 lbs or 296 kg. He died at age 32 and lost a 146 lbs or about 66 kg before that. I was just wondering what your thoughts were on my #378 estimations? Because you do seem like you know your stuff.  (12-15-2019, 03:20 PM)The Panther Wrote:(11-25-2019, 12:44 PM)johnny rex Wrote:@johnny rex(11-25-2019, 05:36 AM)The Panther Wrote:(11-09-2019, 12:56 PM)johnny rex Wrote:@johnny rex(11-08-2019, 03:02 PM)The Panther Wrote: Samson the gorilla. He's one of if not the heaviest gorilla on record, he weighed in at 652 lbs or 296 kg. He died at age 32 and lost a 146 lbs or about 66 kg before that. Not really, I just making guesstimations. If Guhonda's physical/skeletal frame is larger than Samson's, Guhonda could be in the 580-600+ lbs range. Have you seen the picture of Samson's skeleton? His skeleton is very robust. I'll post the picture if I find it.
Samson's skeleton. Note the robust humerus and femur. The skull seems robust too.
(12-09-2019, 01:13 AM)Sully Wrote: On #383 That's forced perspective to the extreme to be fair, no way to tell if he's actually bigger than normal or not Yes, that photo is typical example how some animal can be made to look like much bigger than it is in reality. When people keep in mind, that gorillas are in average around 170 cm tall when standing, it´s easy to notice when something is not right in the photo. But of course, when a woman stands 5-20 meters behind a sitting gorilla, gorilla looks like to be huge. Put there an average male brown bear next to that gorilla and suddenly that "huge" gorilla looks like a child :) |
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