Tara Stoinski, chief scientist of the Dian Fossey Gorilla Fund, answers your questions about primates from Twitter. Why do gorillas pound on their chest? How do apes communicate with one another? Why do chimpanzees have wars? Are there social hierarchies within primate groups? Answers to these questions and many more await—it's Ape Support.To learn more about gorillas and how you can help them visit http://gorillafund.org.Director: Lisandro Perez-ReyDirector of Photography: Chris MarshallEditor: Richard TrammellExpert: Tara StoinskiLine Producer: Joseph BuscmieAssociate Producer: Paul GulyasProduction Manager: Peter BrunetteCasting Producer: Nicholas SawyerCamera Operator: George ZelaskoSound Mixer: Lee BaileyProduction Assistant: Trent BarfieldPost Production Supervisor: Christian OlguinPost Production Coordinator: Ian BryantSupervising Editor: Doug LarsenAdditional Editor: Jason MaliziaAssistant Editor: Justin Symonds
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00:00I'm Tara Swinsky, Chief Scientist for the Dian Fossey Gorilla Fund.
00:03Let's answer some of your questions from the internet.
00:05This is Ape Support.
00:06At Lissy Eager asks,
00:13Why do gorillas pound on their chest?
00:16Does anybody know?
00:17It is part of their display.
00:19It is part of how they show off how big and strong they are.
00:22A chest beat is with an open palm, usually cupped,
00:25and then they beat on their chest like this.
00:27The males actually have these big air sacs underneath their chest.
00:30They're bringing air into these air sacs.
00:32So it sounds like,
00:36This is a lower frequency chest beat from one of the gorillas that we study in Rwanda.
00:45You're hearing the buildup as the male's filling his air sacs.
00:47So when they beat on them, that sound can actually carry up to a kilometer away.
00:51So the lower the frequency that these males can get
00:54actually corresponds with the males being larger in size.
00:58The rival male can get some information while he's still pretty far away
01:01about the size of the male that he's approaching.
01:03And a female can use that information to decide,
01:06is this going to be a good mate for me to join in the long term
01:09and to have my offspring with?
01:10At AfroNuna asks,
01:15Bonobos have this incredibly unique way of settling social conflict,
01:19and that is basically through sex.
01:20It's male-male sex.
01:21It's male-female sex.
01:22It's female-female sex.
01:24One example is if there's a highly prized food item,
01:26so say a ripe fruit that an individual wants.
01:29In a lot of primates, they will fight over access,
01:31and the dominant individual just gets priority of access over that food.
01:35In bonobos, however, they settle that social tension by coming together,
01:39having sex, and then oftentimes sharing the food item.
01:42At Bagelman asks,
01:44Primates are an order within the mammals.
01:47They appeared on Earth roughly 60 million years ago.
01:50These are animals that have high levels of social complexity for the most part.
01:54They have a relatively large brain size.
01:57They have forward-facing eyes.
01:58And currently, there are three main categories.
02:01You have your prosimians.
02:03These are your bush babies, your tarsiers, your lorises, your lemurs.
02:07They are kind of considered the most primitive of the primates.
02:11Then you have your monkeys.
02:13New world monkeys are found in Central and South America.
02:15They include capuchins, spider monkeys, howler monkeys, squirrel monkeys.
02:19And then you have your old world monkeys that are found in Asia and Africa.
02:22And there you think of baboons.
02:24You think of langurs.
02:26You think of blue monkeys, sykes monkeys.
02:28And then you've got the apes.
02:29This includes the smaller apes, the gibbets and the siamangs,
02:32and then the great apes.
02:33Orangutans, bonobos, gorillas, chimpanzees, and humans.
02:37At ItsFaceBaby asks,
02:39How do some apes communicate with other apes?
02:42Is there a secret discord or something?
02:44They communicate a lot through vocalizations.
02:47One of my favorites is what we call the pig grunt.
02:49In gorillas, it sounds a little like...
02:52And it's kind of a mild warning, like, leave me alone.
02:55Another really fun vocalization that gorillas do is called a belch vocalization.
02:59And a belch vocalization sounds a little bit like this.
03:04So particularly when the group is spread out,
03:06you'll hear a belch vocalization there.
03:08And then you'll hear another one over from the bushes over there.
03:10And they're letting each other know that they're around, that everyone is well.
03:14And we even use that vocalization when we're approaching the gorillas.
03:18And it's basically a way to say, I'm here, nothing's wrong, I come in peace.
03:23At JohnnyV45385760 asks,
03:27Hashtag primatologists, how accurate are those new Planet of the Apes movies?
03:32Lots of parts of those movies are accurate.
03:34When you look at Caesar and his clear leadership and dominance,
03:38that's very typical of chimps, where males have hierarchies,
03:41and there will be a dominant male.
03:43And his job is to kind of be in charge of the group.
03:46When you look at the intellectualism of Maurice, the orangutan character,
03:50that's very much what orangutans are kind of known for within the primate world.
03:55Where there were some inaccuracies, for example, is bonobos.
03:58So bonobos are represented as being some of the most aggressive and
04:02evil characters within the movie.
04:04And that's actually not true.
04:05Bonobos are probably one of the most peaceful of the great apes.
04:08We do need to remember that those apes in the movies were genetically modified apes.
04:12So they weren't supposed to necessarily represent how apes in the wild behave.
04:17At Gus802, you know when non-human primates smile, it's actually a sign of aggression.
04:22That is not quite accurate.
04:24It is often used in aggressive situations, but it more often is a sign of submission.
04:30This is an animal showing one of these fear grimaces or submissive smiles,
04:34and it doesn't look like it's very comfortable.
04:36That's in contrast, say, to this chimpanzee that we have here.
04:39It's a much more relaxed facial expression.
04:42The mouth is open, but it's very gentle.
04:44So this would be something that I would say you would see
04:46when an animal is actually quite calm and probably about to play.
04:49But you are correct that teeth are often used in displays of aggression.
04:54This is a baboon showing off their teeth.
04:56And certainly during aggressive displays,
04:58they'll use them actually to bite and attack other rivals.
05:01The other thing is oftentimes,
05:02they'll combine their teeth with other facial expressions to show aggression.
05:06So this is a macaque, and you can see he is showing off his teeth.
05:09And then also his eyes are quite big.
05:11And in macaques, we often see they have these lighter eyelids,
05:14and they'll flash them to let another animal know that they're dominant
05:17or they're not happy with their behavior.
05:19At Ivy Green asks,
05:20LMAO, why do gorillas have two foreheads?
05:24I must admit, I have never thought about it that way,
05:26but I could easily see where someone might make that kind of assumption.
05:30So this is a cast of a male gorilla, which we call a silverback.
05:33What you see here is he's got this heavy brow ridge over his eyes,
05:36which I would imagine is what you're thinking is the first forehead.
05:39But then what's really neat,
05:40and this is actually only found in the male gorillas,
05:42is what we call the sagittal crest.
05:44It's a bony protrusion.
05:45They have these muscles that connect up through here and onto the sagittal crest.
05:50And that's what gives the males amazing jaw strength.
05:53Not so much for feeding because gorillas are vegetarians,
05:56but they're using it to fight other males,
05:58to attract females and defend their families.
06:01At Sip of Tea asks,
06:02If anything attacks us, zombies, aliens, gorillas,
06:05I won't know what to do, I'ma die.
06:07I can't really help you with the zombies or the aliens,
06:10but I can tell you about gorillas.
06:12First of all, they would hear you way before you would probably hear them,
06:15and they would disappear without you even knowing it.
06:17Gorillas, unfortunately, have not fared well against humans,
06:20and so they have a healthy fear of us,
06:22and they would move out of the way.
06:23Now there is an occasion where maybe you could surprise a gorilla,
06:26it didn't hear you coming,
06:28and they will attack,
06:29but really it's just to defend themselves.
06:31A lot of times it might be a bluff charge,
06:33where they come at you and they beat their chest.
06:35It's very rare, and I know of no humans that have actually been killed by gorillas,
06:40so I don't think you have a lot to worry about there.
06:42Chimpanzees, on the other hand, are a little bit of a different story,
06:45and chimps have been known to attack humans,
06:48and actually to grab human babies that they have found and eat them.
06:52But of course, they are more meat eaters than gorillas,
06:55who are purely vegetarians.
06:56At Earth and Space wants to know,
06:58Why do chimpanzees have wars?
07:00Chimpanzee wars are extremely fascinating.
07:04Chimpanzees live in these very complicated societies,
07:07and they're very territorial.
07:08Chimp males will actually patrol their territories.
07:11They get in a single file line,
07:12they walk behind each other,
07:14and they're totally silent,
07:15and they will look for other individuals from neighboring communities
07:18that might have come into their territory,
07:20and oftentimes they will actually kill them.
07:23What's also really interesting about chimps is sometimes these groups will split.
07:27When a community splits,
07:28they'll go and try and eliminate members from a community
07:32that used to be part of their own.
07:34At King Kong in 3D asks,
07:36How well do you think Andy Serkis motion capture performed Kong?
07:40There have been many depictions of King Kong,
07:42but I think that Andy Serkis is maybe the most accurate,
07:46and in some ways the most soulful.
07:48Andy actually came to Rwanda to learn about gorilla behavior from us,
07:52and we spent lots of time out in the field.
07:54I remember one day where there were two gorilla brothers playing,
07:56and they were having a great time,
07:57and they were laughing,
07:58and Andy captured that on film.
08:00And you can see in this clip where Kong is playing with Naomi Watts's character,
08:04and he's also laughing a sort of a chuckle,
08:08and that's exactly what we see gorillas do in the wild,
08:10and Andy had the opportunity to watch these two brothers playing
08:13and doing this exact behavior,
08:15and so it was lovely to see that natural gorilla behavior end up in the Kong film.
08:19At Sheep Kinta asks,
08:20You know, I have no idea where any monkeys or apes live.
08:23I always assumed it was a jungle.
08:25Well, you assumed correctly.
08:26The New World monkeys live in the tropical forests of Central and South America.
08:30Then you have your Old World monkeys,
08:32and they are found in the tropical forests of Asia and Africa.
08:36But interestingly, they don't only confine themselves to tropical forests.
08:40We have the amazing Japanese macaques,
08:42which live in the mountains and are often seen in snow,
08:45and they love to go into these hot pools
08:47and basically, just like us,
08:49sit in a hot pool and enjoy a relaxing afternoon of getting warm.
08:52And then when you come to Africa,
08:54this is where we have multiple species of great apes.
08:57Bonobos are found in only a single country.
08:59Right here, the Democratic Republic of the Congo.
09:02These drawings are approximate,
09:03but this is the only place that bonobos are found.
09:06Then we go to the gorillas.
09:07They're the eastern species.
09:08They have a very small range over here in the countries of Rwanda, Congo, and Uganda.
09:14They're big.
09:15They're hairy because they actually live at high elevations where it is quite cold.
09:19And then you've got the western gorillas.
09:20They live here in countries like Cameroon, Nigeria, Equatorial Guinea, the Republic of Congo.
09:27Finally, you have chimpanzees.
09:28They have the largest distribution of any of the African great apes.
09:32So they start all the way over here in Tanzania
09:34and can come all the way to the west coast in Senegal.
09:38The one great ape that I haven't mentioned is us, humans.
09:42And we are obviously found on every continent on the planet.
09:46At Maybe It's Grace asks,
09:47why do orangutans look like that?
09:50This is a fully adult male orangutan and they have these,
09:53we call them cheek pads or flanges on either side of their face.
09:58These are male secondary sexual characteristics.
10:00We don't see them in females.
10:02Male orangutans make these incredible long calls because they're solitary for the most part.
10:07These cheek pads may help sort of broadcast that message out there.
10:11It's likely also one of the characteristics that females use when they're picking a mate.
10:16Some male orangutans can choose to not develop these characteristics
10:20and they can actually stay in a form that looks more like a female.
10:23And what this means is that they'll often be tolerated by the adult males in the area.
10:28Maybe because they don't recognize them as a male and it's competition.
10:31If there is a male like this in the vicinity and he disappears,
10:34maybe he moves off or dies.
10:36These males that have the more female morphology can then develop
10:40into a fully flanged adult male.
10:42Orangutans are the most arboreal of the great apes.
10:45So they spend lots of time in trees.
10:47So they have these long arms that can help them move between tree to tree.
10:50And they have these enormous hands and their thumb is placed pretty far back on their hand.
10:56It just gives them more space to be able to grab onto large tree branches
11:00than if their thumb was kind of a bit higher up like ours is.
11:02At Tinterdrone asks,
11:04Are most primates monogamous or not?
11:07There are some species that we see in Central and South America
11:10called marmosets and tamarins.
11:12They are often monogamous.
11:13Most primates, however, are not monogamous.
11:15And the two reproductive strategies we see most of the time,
11:18one is polygyny.
11:19And that is where one male will mate with multiple females.
11:22The silverback male of the group generally mates with all of the females.
11:26And then you have a promiscuous mating structure.
11:28And that is where both males and females will mate with multiple members of the opposite sex.
11:33That is commonly seen in chimpanzees, for example, in baboons.
11:37By mating with multiple males, you're confusing paternity.
11:40That no one male knows he is the sire of that offspring.
11:43And so hopefully all of them will be invested in helping to make sure
11:46that that offspring stays safe.
11:48At Grawkay asks,
11:49How do gibbons choose their mates?
11:51What we do know for gibbons is that they are one of the few primate species that are monogamous.
11:56So males and females will spend long periods of time living together.
12:00They do something called duetting, which is an absolutely beautiful sound.
12:04The duet involves both of them singing together,
12:07making this very unique sound that can be heard for long distances through the forest.
12:11Here's an example actually of a gibbon duet.
12:17It is definitely one of the most unique vocalizations that we hear in the primate world.
12:21At Element 82 wants to know,
12:23Why do gorillas get to be so f***ing ripped from eating leaves and not lifting?
12:28Not fair.
12:29Gorillas are the largest primate on the planet.
12:31Male gorillas can weigh around 400 pounds.
12:34And you are right.
12:34They are ripped 100% muscle.
12:37So they do only eat plants.
12:38And plants do have a lot of protein.
12:40But they do have an extra advantage that we don't.
12:42And that's their digestive system.
12:44So they have a much larger intestines than us.
12:47And particularly the large intestines is bigger than us.
12:49And they do something called hindgut fermentation.
12:52There are microbes in their digestive system that are helping them
12:57break down that fibrous plant material in a better way than just their own enzymes can do.
13:02And it means that they are able to extract more nutrients out of plants
13:05than we would actually be able to.
13:07One of the questions that I get asked most frequently about gorillas is like,
13:10how strong are they compared to humans?
13:12And I don't really know that we have the definitive answer.
13:14What I hear out there is that they are roughly 10 times as strong as we are.
13:18So this is a replica of a male gorilla hand.
13:22It's true to size.
13:23You can see how actually enormous their hands are.
13:26At SDF4041SDF404 asks,
13:31What are the social structures and hierarchies within primate groups like monkeys and apes?
13:36Within primate social groups, there's generally always hierarchies.
13:39Bigger males are often the ones that end up becoming dominant.
13:42They use a lot of those secondary sexual characteristics,
13:45the big canine teeth, the large size, to fight for access to dominance.
13:48And they want to be dominant because that's what gets them the opportunities to breed.
13:52In gorillas, for example, we will have one very large male, the silverback.
13:56His job is to protect the group.
13:58It's to decide where the group's going to go.
14:00In other primate groups, you might find that females are actually dominant.
14:04And we see that in bonobos.
14:05Baboon females stay in the group they were born in for their entire lives.
14:08So they've got all their female relatives around them.
14:11And they organize in matrilines.
14:12So if your mom is the dominant female and you're a tiny little baby baboon,
14:16you will be dominant over all the other females in that group
14:20because guess who's backing you up should someone pick on you?
14:22Your mom, who is the dominant female.
14:25At Autumn Lupin asks,
14:26Do primates have culture?
14:28I don't know. I'm not a f***ing primatologist.
14:30Well, I am a primatologist.
14:32And I can say that yes, primates do indeed have culture.
14:35Culture are behaviors or traits that have been passed down not through genetics,
14:40but learned from one generation to another.
14:42One great example that I love from chimpanzees is this behavior called leaf clipping.
14:47So a chimpanzee will put a leaf in their mouth and then rip it.
14:50In one population of chimpanzees, this is an invitation to play.
14:54And in another population of chimpanzees, it's actually an invitation to have sex.
14:58Another example that we see again in chimpanzees is how they groom each other.
15:01Instead of just sitting next to an individual and going through their hair,
15:05they'll actually put their arms up and clasp.
15:07And they'll hold their arms like that while they're doing the grooming.
15:10And it's very unique to a particular chimp population.
15:13At Dabian TM, I'm gonna be real with you guys.
15:16What the f*** is a slow loris?
15:18Slow loris is a prosimian.
15:20So these are kind of the most ancestral primates that we have out there.
15:24They're found in Asia and they're nocturnal.
15:26So those big, big eyes that you see help this animal forage at night
15:30by capturing moonlight or other light that may be out in the environment.
15:34At Seager Daily says, do primates laugh at farts?
15:38Boy, I wish they did because they do spend a lot of time farting.
15:42In particular, gorillas that I work with, they eat,
15:44you think about it, 60 pounds of vegetation a day.
15:46They're producing a lot of gas.
15:48There is a lot of farting, but they pretty much ignore it.
15:51I've never seen them laugh at it.
15:53It's just a part of what happens on a daily basis for them.
15:56Rachel Osiris asks, what's a prehensile tail?
15:59It is an adaptation where a tail can actually act as an appendage.
16:03So you can use it, if you're a primate, to hold on to branches, to move.
16:07You can think of it as kind of like a fifth arm or leg.
16:10Interestingly, they are only found in New World monkeys.
16:13So we only see them in species like howler monkeys and spider monkeys.
16:16You won't find monkeys that are in Asia or in Africa having this prehensile tail.
16:20Instead, their tails are used more for balance.
16:23Apes are actually characterized by not having tails.
16:26They have a much more balanced sort of upright center of gravity.
16:29They walk and walk upright.
16:30And so needing that tail over time was just not as necessary as it was for
16:34the monkeys that are really confined much more to the trees.
16:37At Rich Lizard asks, how do chimps understand numerical order?
16:41How did they learn it?
16:41There's been a lot of interest in ape cognition in general.
16:45And one of the areas that people have studied is their understanding of numerical order.
16:48And there's a study where they have numbers presented on a screen,
16:51and they can actually put them in order from 1 to, say, 18 or 19 or 20.
16:55Now, we don't really understand what chimps know here.
16:58What they could easily learn is just a sequence of orders.
17:01This number, number 1, is always followed by number 2.
17:04Number 2 is always followed by number 3.
17:06But there have been other really interesting studies
17:08done that show that they do have an idea of numbers and of numerical concepts.
17:13Researchers will put down a choice between a 3 and a 5, say.
17:18And whichever number the chimpanzee picks, another chimpanzee will get that many treats.
17:24So if I pick the 5, my partner will then get 5 treats, and I will get 3 treats.
17:31Chimps are really good at picking the number that will give them the best treats,
17:35which I just think is amazing.
17:36At Matt Potter 79 asks, have you seen the footage of the chimp hunting fish with a spear?
17:42They have entered the Stone Age.
17:43This, I think, references back to a video that went kind of viral of a primate using a tool,
17:49this orangutan, holding itself out over water and using a stick to manipulate its environment.
17:54Allegedly, this orangutan had seen some fishermen nearby and was copying their behavior.
17:59We have seen orangutans copy very specific behaviors.
18:02For example, orangutans in zoos that have seen their keepers do certain cleaning routines,
18:08use a bucket, put water in it, get a rag and clean.
18:10Orangutans that have seen their keepers put a hat on will do the same thing.
18:14If they're given a hat, they might put it on their head.
18:16So that may have happened in this situation.
18:17It's certainly not out of the realm of possibility.
18:20Tool use is not something new to primates.
18:23We've known about tool use now for more than 40 years.
18:26And in fact, it was the pioneering work of Dr. Jane Goodall that first showed us that
18:30chimpanzees use tools for a variety of things.
18:32At the time, it was thought that only humans use tools.
18:35And it was one of the things that we use to define what makes us different from other animals.
18:40We soon learned that chimpanzees use tools.
18:42They have hunted with spears.
18:44They use sticks to fish out termites.
18:46They use moss as a sponge to get water.
18:48But we also know now that lots of animals use tools.
18:51So we see tool use in dolphins.
18:54We see tool use in elephants.
18:55We see tool use in certain types of birds.
18:58At burglehobbit asks, good morning, everyone.
19:00Do any of you know what's the lifespan of a great ape?
19:04Great apes generally live to be in their 30s or 40s if you're a gorilla.
19:09For the most part in the wild, great apes have shorter lifespans than they do in captivity.
19:13At beamboy asks, what do apes and gorillas do when they're sad?
19:17One of the saddest things to see is if a gorilla loses its family.
19:21They will often do these hooting vocalizations,
19:25where they're calling out and trying to find other members of their group.
19:28One of the amazing things that we see, they have empathy.
19:32And so oftentimes they will come over and they will console them.
19:34They will put their arm around them.
19:36If they're young, they'll often hug them.
19:38We've also seen that when gorillas die, other gorillas will go through a mourning period.
19:43So they don't want to leave the body.
19:44They will lay next to the body.
19:46They will groom the body.
19:47Sometimes they will even push or shove the body a little bit as if to say,
19:51why aren't you moving?
19:52Apefellas asks, did you know all great apes are endangered
19:56and that four of the six are critically endangered?
19:58Yes, sadly, I did know that.
20:00Of the 500 species of primates on the planet,
20:04two thirds of them are considered endangered.
20:06And great apes are among the most endangered.
20:08So at most we might have a couple hundred thousand chimpanzees,
20:13a couple hundred thousand gorillas.
20:14The mountain gorillas that I work with in Rwanda,
20:17we have a thousand of them left on the planet.
20:19That's it.
20:20Sumatran orangutans, 13,000 of them left.
20:23Bonobos, we estimate between 15,000 and 20,000 of them left.
20:28The Nigerian Cameroon chimpanzee, maybe less than 10,000.
20:31So this is a critical time for great apes because not only are they endangered,
20:35but our estimates are of the ones that we have left,
20:38we will probably lose half of them within the next 20 years
20:41from things like deforestation, climate change, and hunting.
20:44So it is really sobering situation for apes in the wild.
20:48At 3BI Concept Inc wants to know,
20:50who was Dian Fossey and what is she famous for researching?
20:54Thank you so much for that question.
20:55I love to talk about Dian Fossey.
20:57She actually founded my organization.
20:59So Dian Fossey is a woman that went in 1967 to Rwanda
21:05to study the then pretty much unknown mountain gorilla.
21:07She didn't have a scientific background, but she loved animals.
21:11And what Dian Fossey did was get accepted into gorilla society
21:15and told the world the story of them and their amazing social life,
21:19how family oriented they are,
21:21and changed our perception from ferocious beast to gentle giant.
21:25These are the gorillas that she knew.
21:27They all had individual names.
21:29And what's amazing is they all have individual nose prints
21:32the same way we have individual fingerprints.
21:34And that is how she identified them.
21:36Down here, we have Shingaza.
21:38Shingaza was born in 1982.
21:40She's actually a gorilla that I had the opportunity to study as well
21:43when I started working with the Dian Fossey Gorilla Fund.
21:46So it was a real honor for me to be able to study
21:48some of the same gorillas that have been studied by Dian Fossey.
21:50When Dian Fossey went to Rwanda,
21:52she quickly saw that these animals were endangered.
21:55They were being killed for trophies.
21:57People thought it was cool to have a gorilla head on their mantle
22:00or a gorilla hand as an ashtray.
22:02And so in addition to the research,
22:04she started doing what she called active conservation,
22:06which was going in and removing snares.
22:08They're sort of set on a branch.
22:10When the gorilla walks through them,
22:12they pull and they catch the gorilla's arm.
22:14We remove thousands of these a year
22:17to help protect gorillas and other wildlife from getting caught.
22:19But this work originally started with Dian Fossey.
22:22She was afraid that mountain gorillas would be extinct by the year 2000.
22:26Instead, right now, they are the only great ape on the planet,
22:29besides ourselves, that are increasing in number.
22:31So those are all our questions for today.
22:33I love hearing how interested you are in primates.
22:36You heard that they need our help, so please get involved.
22:38And thank you so much for watching Ape Support.