nowhere to go. again, the american red cross, as always, on the scene, and we're going to follow this breaking news for you here on cnn, just as long as this system is active and it is moving, it is moving across a big portion of the country. we know you can predict these tornados, like where they're going to happen, the storm system but you don't know quite exactly where they're going to go and just the power and the size of them until they hit the ground and until possibly it is too late. so, everyone, i'm don lemon, it is the to the hour, again, i want to tell you we're following this deadly storm system in the southern states right now. emergency officials say seven people are dead in mississippi, alone, two of them children. and you need to be on alert this hour if you're in alabama, kentucky, or tennessee. already there are dozens of unconfirmed reports of tornados from northern missouri through mississippi. and perhaps, the most destructive one nit yazoo city, mississippi, before the storm cell traveled across the state and then into alabama. a tornado that blasted through

there was almost a mile wide. yazoo city fire chief says 20 to 30 homes are destroyed and he believes some people were inside of those homes. search-and-rescue efforts are now under way at this hour. overall, 12 counties are reporting injuries and that's according to mississippi emergency management agency. let's get to our expert here, jacqui jeras. jacqui? >> ah what an amazing day it's been, don. this is a high-risk tornado day as we call it and you only get a handful of days like this a year and exactly what happened in mississippi, as why we've been telling you about this for days. the threat of tornados ongoing this evening and even into tomorrow so we still have quite a ways to go with this severe weather threat in this event. we have watches in effect extending from missouri and illinois, stretching all the way down into the panhandle of florida. i kind of tried to spell this out for you, more specifically, to let you know when these warning times expire from 8:00 all the way from 3:00 in the morning for this most recent watch from ohio stretching down

into eastern parts of tennessee. now we do have some tornado warnings in effect as we speak. christianson counties in illinois, just east of the springfield area. this storm has a history producing some wind damage. this is a doppler indicated tornado but any could touch down at any time. northern parts of alabama, coleman county. doppler radar indicating tornado here stretching up from the north and the east, about 55 miles per hour. so when those warnings go off you need seek shelter immediately because they are coming very, very quickly. there's also a line, a very nasty weather just to the west of nashville, not much in terms of warnings on this, but you're going to see a lot of lightning, heavy downpours, and gusty winds that can cause some damage. so be aware. there you can see those live lightning strikes right through the nashville area as we speak. now, we were talking about ef scales and what kind tornados

these can cause, we don't have the official word yet out of jackson, mississippi, how strong this tornado was but based on the pictures i've been seeing, don, i would say at least an ef-3 tornado, which would be considered a severe tornado and winds around 165 miles per hour and i've also seen a couple of pictures where some of these homes have been wiped clean off of the slates and if that is case and these are well-constructed homes maybe see this upgraded to an ef-4 or more so we'll watch that and of course as we get word from them tomorrow we'll bring that along to you so this threat continues overnight with that high risk, don, especially mississippi, alabama on into western kentucky and tomorrow this moves into the eastern seaboard and though tomorrow while we're expecting severe weather we don't anticipate as many strong violent tornados. >> yeah, don't anticipate. we never know what will happen. jacqui, just unbelievable. jacqui jeras, thank you. jacqui's watching this for you. make sure you stay tuned. we will cut into our next program. i'm don lemon.

i'm i'll see you back here at 10:00 p.m. eastern. that storm system, so stay tuned right now for "planet in peril." we begin our journey here in central africa where a rising food prices are pushing deeper and deeper into previously untouched forrests. they're just trying to make a living, of course, clearing land, hunting for food. the problem is, not only are they threatening fragile habitats and wiping out animal populations at an alarming rate, they're also exposing themselves to potentially deadly viruses. viruses which once unleashed in humans can quickly spread around the world. these forests may seem remote, but what's happening here now affects us all.

>> january 2008. rising food prices touch off riots around the world. in haiti, ten people died. in cameroon, 20 are killed. unable to afford basic supplies, people increasingly turn to the forests for food. june 2008, deep in a remote region of cameroon, two hunters stalk their prey. their names are patrice and patty. they're searching for bush meat. forest animals they can kill to feed their families. they set out most days to go out hunting in the forests around their homes. they have a series of traps, of snares that they've set up. they'll catch wild pigs, snakes, monkeys, rodents. anything they can really.

pat ris and patty have been out for hours but found nothing. the animals are simply gone. not too far away, dr. sanjay gupta is with another hunter. but he, too, is finding his traps empty. >> it really gives you an idea of just how hard it is to actually get even a little bit of food. diddy, who is trying to provide enough food for nine people tonight, he doesn't really care what he gets at this point as long as he gets something. i can tell you, we still have a long ways to go. it is hot, it is humid, it is a lot of work. >> hunters have to keep going deeper into the forest but that is where hidden danger lurks. forest animals are a reservoir of viruses. microscopic pathogens living in the animals' blood. some are harmless but some are potentially deadly when passed to humans. >> individuals have been infected with these viruses

forever. what's changed, though, is in the past you had smaller human populations. viruses would infect them and possibly go extinct. viruses actually need population density as fuel. >> dr. nathan wolff is a world renowned epidemiologist, a virus hunter. he works in these forests, tracking what he calls zoanotic viruses, ones that can jump from animals to human. it's zoanotic viruses that scientists say could trigger the next pandemic. >> when i look around in this forest, part of what i'm thinking is, what's the diversity of viruses out there? >> it may sound far-fetched, but it's already happened. hiv is the deadliest example. it was in a forest not too far from here in southern cameroon that scientists now believe that hiv was born. they say it started with a chimpanzee, infected with several strains of viruses by eating smaller viruses. an infected chimp's blood must have then come in contact with

the blood of a human being. most likely, say scientists, a hunter or someone cutting up the chimp for cooking. that simple, seemingly insignificant transmission set off a global epidemic, a pandemic that so far has killed tens of millions of people. scientists now believe hiv crossed into humans in the early 1900s. but it wasn't until air travel increased that it spread and became a global epidemic in the 1980s. is it inevitable that there will be another pandemic like hiv? >> yes. the human population is going to have pandemics. that's just the nature of how we operate now. we are so profoundly interconnected that it will be the case that things will enter into the human population and they'll spread globally. >> hiv may be the most well-known virus to cross over from an animal to a human, but there are many others. and many we don't even know about. that's why wolff has created

what he calls a global viral forecasting initiative. a kind of early warning system in virus hot spots around the world to track the transmission of viruses. he's worked in cameroon for nearly a decade monitoring hunters and those who butcher bush meat. both activities where human and animal blood are constantly in contact. dr. wolff likens his work to the way an intelligence service tracks threats made by potential terrorists. if he can track what viruses are crossing into humans, what he calls the viral chatter, he hopes to stop the next virus before it spreads. >> each one of the species of animals has their own sort of repertoire of different organisms. viruses, parasites, bacteria. and anytime that humans are in contact with those animals, there's going to be the possibility for the jump-overs. that's what we're considering the sort of chatter. the pinging, if you will, of viruses from these animals into the human population. and most of the times the ping just bounces back.

but every once in a while, it sticks. >> it's sticking more often. the national academy of sciences says 75% of the world's emerging diseases jump over from animals. the sars virus crossed from civet cats in asia to infect thousands and kill more than 700 people in more than 20 countries. avian flu jumped over from birds around 2003 and killed more than 200 people. the origins of many other zoanotic viruses are still unknown. ebola has killed hundreds over the past decade but its origins remain a mystery. if scientists don't know where a disease starts, it usually means it can't be stopped. it's been hours in the forest for both our teams. chasing prey that seems to vanish.

we stop for a drink of water. then there's a rustle in the brush. a group of hunters approach. their packs loaded with wild game. there is at least three viruses that you know about which are in this particular monkey. >> this species, yeah. and there's many, many more pathogens that are present in these animals.

in the forests of cameroon, dr. sanjay gupta and i have split up. we're both following men hunting for animals or bush meat. patrice and patty, the two hunters we've been with for the last couple of hours haven't been able to find any game today. they've been unlucky, but today we did come across this group of hunters who have several packs

full of animals that they've caught. >> this monkey is potentially is infected with retroviruses. >> nathan wolff is concerned about what unknown viruses these animals might carry, viruses that could make their way into the human population, touching off a pandemic. >> there's at least three viruses that you know about, which are in this particular monkey? >> this species, yeah, yeah. i mean, there's many, many more pathogens that are present in these animals. these individuals are at specific risk. particularly, you know, depending on the level of contact. if there's blood contact, they're at risk for transmission and possibly infection with novel viruses. >> as the hunters display their kills, something surprising happens. they show us filter paper they've used to collect the animals' blood. the blood will be tested for zoanotic viruses, part of a program dr. wolff has spent years setting up. does it surprise you that we've run into two groups of hunters out here and they're all carrying the filter paper that you've been teaching them about?

>> yeah, no. i mean, from our perspective, it's a good indication of the coverage we have. so this is from this animal right here. greater spot-nosed guenon. these individuals, every person who has one of those filter papers has, at least at a minimum, been through our basic health education about the risks associated with these activities. which presumably from our perspective gives them the ability to decrease their own risk and then obviously the risk to their families, the village, the country and the world. >> once bush meat is taken out of the forest, you can find it for sale everywhere. on the side of the road, there's pangolin for sale, snakes, monkeys and markets selling bush meats are packed with people. >> would you check the blood of these monkeys at all? >> absolutely. >> dr. wolff estimates 4.5 million tons of bush meat are taken from central africa's forests every year. a task force of leading

conservation groups says the bush meat trade is the single biggest threat to africa's animal species. and that's making it more of a threat to humans. >> contact with some animal in this remote village that previously might have led to the jump of a virus into that community that would have maybe infected a few people, maybe infected one person, probably would have died out. now all of a sudden that remote village is immediately connected to the major city and through air transportation and ships, through the rest of the world. so it's something that's in the middle of nowhere here, for example, can potentially, you know, be in new york in the course of 48 hours. >> health officials aren't sure how many animals are humans -- >> jumped to more than 30 humans. >> there may be other individuals with ill animals. >> in 2003, americans were shocked when a rare zoanotic disease called monkeypox infected dozens of people in the midwest. >> the disease has spread to wisconsin, illinois and indiana. >> like fever. >> turns out it was caused by

african rodents imported into america as pets. that outbreak was quickly contained. >> but in central africa, monkeypox continues to kill. dr. wolff takes sanjay and me on a long journey from cameroon to the democratic republic of congo where 20 people have just died from a monkeypox outbreak. we fly to a remote town called loja, where in a walled compound, we find coy alone in a small hut. >> now, we're standing out here and she's inside there. why is that? >> so the first thing you need to do is to isolate the patient. >> he is a local scientist working with dr. wolff's team. >> are we at risk? how contagious is this? >> just looking at the patient, you have no risk. but when you are in contact, direct contact with the patient, at that time you are in danger.

>> coy is the latest victim. all of these people are slowly recovering and are still quarantined in this makeshift clinic. painful sores cover their bodies and they say they feel tired all the time. >> if she hadn't made it to you, to this place, what would happen to her? >> some patients recover but others die. >> coy probably got monkeypox through contact with bush meat, which she says she handled over the past few weeks. or she came in contact with an infected person. its exact origins are still unknown. it's unlikely monkeypox could become a pandemic because it loses strength as it passes from person to person, unlike hiv. coy will have to stay quarantined for weeks. there's little the medical team can do for her aside from hoping

the monkeypox runs its course and she survives. for dr. wolff, coy's case is both a warning and a sign of things to come. >> we're just tapping the surface. we've got the tip of the iceberg when it comes to our knowledge of the different viruses that are out there. and by documenting them, potentially to get in a space where we can prevent pandemics instead of waiting for aids to happen and spread globally, to actually catch it earlier and potentially save millions of lives. >> great white sharks are the most feared animals on the planet but a still that we don't know about them. we decided to get in the water for ourselves and find out.

when great white sharks start to circle your boat, the feeling is unsettling. 15 feet long, thousands of pounds, these are the animals of so many nightmares. >> this is a famous shark, ely. >> we've come to dive with the great whites to get an up-close look at them and the battle that's being waged around them. >> please do not go down unless we tell you to. >> mike takes tourists cage diving with great white sharks off the coast of south africa. >> and then you can lean back and be comfortable. >> it's become a big business but it's also, he says, a conservation effort. he thinks if people can see these endangered animals under water, they'll learn to appreciate them and want to help protect them.

cage diving, however, is highly controversial. we'll tell you why in a second. but right now the water is filled with blood and fish parts called chum. and the great whites have arrived. is there any recommendations for what to do? >> well, basically, don't scare the sharks. you're going through the water -- >> i'm not worried about scaring the sharks. it's usually the other way around, i think. after we get used to being in the water with the sharks inside a cage, we have the chance to do something few others ever have, we'll go swimming with great white sharks without a cage. smart...you're staying at this resort for free? how?

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climbing into a shark cage is scary. the sea is chummed with blood and fish parts and underwater visibility is low. at first, all you see is a vague shape moving fast. then, all of a sudden, you find yourself face-to-face with a great white shark. its mouth open, its eyes rolling back into its head. it's one thing to see a great white shark from above but to be actually down in the water, six, seven feet away from one, it's an extraordinary experience. this experience has become a major draw for tourists. each one of these people paid $150 to visit this reef off the coast of south africa, known as shark alley. >> there's the great white

shark. >> it's one of the best places in the world to see great whites and shark tourists bring in more than $30 million every year to south africa. but is this really good for sharks? >> whoa. >> the battle lines are drawn. at issue is how the sharks are brought to the boat, chumming, mashed up fish parts and blood are thrown into the water and the scent attracts the great whites. once the sharks arrive, a tuna head attached to a rope is used as bait to lure the sharks to the surface and get thom lunge at the cage. >> the bite's a visual reference to the smell. all we're doing is we don't take the bait, we try to pull the bait a little bit closer so the animal can come closer to the cage, so people can see a little bit better. >> it does sometimes get the bait? >> it does sometimes get the bait. that's unfortunate. >> critics say it's more than unfortunate, they say it's dangerous. when the sharks get the bait, it

teaches them to associate food with humans in the water. and that, some locals believe, is encouraging great whites to try to eat swimmers and surfers. craig boven thinks cage diving could be why a great white almost killed him. boven was diving for lobster on this beach near cape town in 2005 when he was attacked. >> i just clamped on on both of my arms, chicame out of that impact, i was still inside his mouth and he was slowly swimming with me. >> the shark was dragging him out to sea. after he overcame the shock of what was happening to him, he began to fight back. >> so i started putting my knees into his belly and i saw that that was having some effect on him and i head-butted him with my mask on his nose and carried on this tussle for quite a

while. >> you're wrestling with a shark under water? >> yeah. >> and i realized i wasn't getting out. so i just pulled on my right hand. i thought i was going to leave my hand inside. i pulled and my arm came free. >> so this bite here, here -- >> that's it, yeah. >> both of boven's hands were mangled and his right one is permanently damaged. today he still surfs and dives in the same water where he was diving and chumming's most vocal critics. >> you cannot find a single example of people feeding and attracting and baiting animals that has been successful. it's a no-no. >> with no other animal do people bait or chum. i mean, to go see the lion, you don't throw out food. >> they used to. nobody would even think about doing that anymore. >> shark tour operators can't do it anymore in florida and hawaii. after a series of vicious shark attacks, chumming was banned in

both states. but shark tour operators in south africa point out that even though shark tourism has risen dramatically in the past decade, shark attacks have not. on average, there are around five attacks on humans every year in south africa. but craig boven and others insist the behavior of sharks is changing. normally if a shark bites a human, they release them. but the shark that attacked boven did not. and in the last four years there have been at least two deadly attacks in which the sharks eat their victims whole. so who's right? unfortunately, the science to support either position isn't easy to come by. for all of our fear and fascination with great whites, they remain a mystery. there's so much we simply don't know about their behavior. they've never been seen mating or giving birth, for example. and though they're classified as an endangered species, we don't even know how many of them there

are. alison is a marine biologist studying the effects of cage diving on the feeding habits of great whites. she's tagging great whites with darts attached to transmitters. she can then track the shark's movements around the waters for months. >> here we go, here we go. keep it there, keep it there. >> tagged. >> she's tagged over 70 sharks so far. the data she's collected led to the only peer-reviewed studies on the effects of cage diving on shark behavior. >> the study that we did showed a surprising result in that the sharks, most of them, stopped responding over time to the boats. >> so you don't see any connection between increased shark attacks in this area and shark tourism? >> no, not at all. all the evidence we have at the moment finds no links between chumming and shark attacks. we are definitely not on the shark's menu.

>> mike ruddson's so sure we're not on the shark's menu, he stakes his life on it. he's one of the few people in the world willing to swim with great white sharks without a cage. he's been doing it now for ten years. he believes to understand the true nature of great whites, you have to do it without a cage. you have to meet the animal on its own terms. so we decided to join ruddson under water so we, too, can come face to face with this most feared predator of the sea without a cage. it gets your heart beating. it doesn't take much; an everyday moment can turn romantic at a moment's notice. and when it does, men with erectile dysfunction can be more confident in their ability to be ready with cialis. with two clinically proven dosing options, you can choose the moment that's right for you and your partner. 36-hour cialis and cialis for daily use. cialis for daily use is a low-dose tablet you take every day, so you can be ready anytime

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hello, everyone. don lemon here at the cnn headquarters in atlanta. breaking news the death toll in mississippi now stands at nine. it is rising and it could rise after a deadly storm system tore right through the southeast. two of the victim, we're told,

are children. and you need to be on alert this hour if you're in alabama, kentucky or tennessee, or anyone in the path of this storm system. already there are 43 unconfirmed reports of tornados from northern missouri, right through mississippi. perhaps the most destructive one hit yazoo city, that's in mississippi, before the storm cell traveled across the state and into alabama. the tornado that blasted through there was almost a whole mile wide. the yazoo city fire chief says 20 to 30 homes are destroyed. and he believes some people were inside of them when that tornado came through. search-and-rescue of the s are under way at this hour. let's go over now to our meteorologist jacqui jer awho's been tracking this all for you, throughout the evening. jacqui. >> dorng the threat remains widespread at this hour from parts of missouri, stretching wall way down the panhandle of florida. our most recent watch isured here to cover parts of alabama.

northwest georgia and including the metro atlanta area until 2:00 in the morning. a good indication that these storms will be holding together and continue through the overnight hours. make sure that you have your noaa radio on before you go to bed. six miles east of coleman, alabama. this continues to move quickly up to the north and the east and to put it into perspective for you here's huntsville in birmingham, just down do the south, so kind of sandwiched about halfway in between the of 2 of those. we also have a very intense line north and west of nashville. just new tornado warnings issued here. doppler radar indicated near the state line, moving over towards kentucky, and we have seen this continuing throughout much of central kentucky at this hour. now, we have a high risk of these tornados continuing, these large, violent tornados that stay on the ground for a very long period of time and so it's this big purple area, mostly where we have the watches now

that we think that that greatest threat will continue. this will move eastward through the overnight and through the day tomorrow, we'll have that risk of severe weather, say, from parts of pennsylvania in the mid-atlantic states down through the carolinas and even into parts of florida. however, tomorrow, the threat not quite as strong in terms of getting rotating storms as what we've been seeing tonight. don, this has been a really rare event of what's been taking place. this happens only a couple of times a year. it's been an unusually quiet severe weather season so far. i mean, this is late april and this is really the first big outbreak that we've seen, and this could be one of the strongest, easily that we'll see throughout the year. we'll know to track these storms and let you know, nashville, we're a little concerned about it at this hour. nothing severe to your west but heavy downpower downpours. >> jacqui jeras watching it all from the cnn severe weather center. jacqui, thank you. we saw you live on the air it was seven and now we're being

told nine people dead and just moment ago i spoke with cnn's ed lavend d lavandera who just arrived in yazoo city, missouri. >> reporter: we just arrived at yazoo city and our first glimpse whether we saw as you see along the highway 49 the main road that brings you into in city, you see about a half-mile wide swath off of that highway where this storm's essentially ripped apart many the businesses, restaurants, they were right there on that stretch of highway and then back in -- into -- off of the road you see where the storm cut through and essentially just clipped hundreds of trees in half. we just arrived and we're told that the damage really kind of begins where we're at and stretches back a mile and a half off of this highway. so we're in the process of trying to get a sense and get back in there as best we can so that we can do our best to assess the damage. >> and, ed, i imagine people are devastated. have you had a chance to speak to any residents, anyone who witnessed this or is affected by it? >> reporter: yeah, actually one

of the first people that i met here when we got out of the car was a couple by the name of rob and ashley. and they just told me this horrifying story how essentially they were caught in the middle of this tornado as they were driving to their father's restaurant. they were in their car trying to race over to the restaurant so that they could hide in the freezer of the restaurant. but they couldn't make it in time. the car windows exploded. the car was picked off the ground, they say, and tossed several feet. and they told me in their words they thought they were about to die. >> ed lavandera, stay safe. ed, thank you. a story that we'll be following throughout evening. meantime, i'm don lemon, back to "planet in peril" right after this. (s. phillips) malaria is the number one killer of infants in africa. exxonmobil has many employees in africa

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preparing to swim with great white sharks without a cage produces two reactions. the first is, well, fear.

it's hard to believe you're about to actually do this. the second reaction is a surge of adrenaline. it definitely gets your heart beating. mike ruddson knows that better than anyone. he's dived with great whites without a cage hundreds of times. he once even caught a ride on a great white's dorsal fin. he insists these animals might be top predators but they're not the man-eating machines so often portrayed in movies. we decided to take him up on his offer to dive with sharks without a cage to see the great whites in their natural state. what do i need to know before going down? >> whatever you do, don't make fast movements. what we are is the same as a jackal at a lion feed. as long as the jackal behaves it doesn't get killed. >> we're like a jackal in a lion feed. the great whites are the lions, we're the jackals. >> exactly. >> they'll let us be there as long as we don't interfere with them.

>> don't try to grab a bite and run away. >> the water is filled with chum, fish parts and blood. a number of sharks are already circling the boat. so it's time to go. to get to the bottom, i climb into a cage which is lowered about 20 feet to the ocean floor. mike's already there scouring for any sharks. then he signals for me to swim out. almost immediately, my weight belt falls off. struggling with that is the last thing you want to do around great whites. the current is really strong and mike has me hold on to a rock to stay in place. visibility is low. but then, suddenly the sharks come into view. it's clear they see us, but

they're keeping their distance, gliding by slowly, gracefully. it's remarkable to see them like this, to be so exposed to an animal that's so feared. mike warned me they don't like the sound of air bubbles and told me to hold my breath when they got near. truth is, my heart's pounding so fast, holding my breath is almost impossible. at one point, there were four different sharks swimming around us. it's important to stay alert. but after a while, i'm also able to appreciate the beauty, the power of these animals. widely hunted, universally despised, capable of such destruction. and, yet, when you see them like this, not lunging after bait, but simply gliding through the water, you see them in a different way. you understand there is more to them than we know. we stay down for more than 30

minutes until our oxygen nearly runs out. >> seeing it so close is -- >> yeah. >> -- never seen anything like it. it's amazing. you can get a totally different sense from seeing them like that versus a cage attacking a piece of bait. >> they're just trying to be sharks. >> they're just trying to be sharks. but the truth is, we really don't know enough about what that means. as long as our knowledge of sharks and the role they play in our oceans is dwarfed by our fear and our hatred of them, the fight over their future will go on. next on "planet in peril" mountain gorillas. >> we've been hike for nearly

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in ru wanda's park where hiking into the mountains to see an animal threatened by conflict on the brink of extinction. we've been hiking already for nearly two hours. we're not sure how much further up the gorillas are. we're heading to a group of mountain gorillas that have not been visited by tourists before. they're not habituated in the same way. they've only been studied by scientists. before we enter the park,

veronica, the wildlife biologist telling us there's a lot of aggression in the group of gorillas we're going to visit. that should be interesting. gorillas are always on the move. searching for food and a place to rest. trackers have gone up ahead of us to locate the family and radio us the coordinates. but even with the extra help finding them isn't easy. nearly three hours into the hike, there are signs we're finally getting close. >> those are fresh tracks. >> we finally find them in a large clearing and come face to face with one of the family's flatbacks, a young male. our trackers grunt, signaling we're not a threat, and he lets us go by.

it's an amazing sight, 43 gorillas in this single spot in the forest. about 20% of rwanda's entire gorilla population. this family is called a pablo group, named after the male silverback who used to be in charge. pablo is still around, but another silverback, kansbey, is now the boss. >> that's the silverback. that's the adult mail -- male? >> an adult male can weigh about 400 pounds and eats up to 60 pounds of vegetation a day. >> she transferred for one of the groups. >> a biologist and director of

data and research for the diane fossey foundation studies the three research groups. what's the value of having a group that's not a tourist group that's just a research group? >> continuing the research in gorillas is always important. give a lot of information in terms of population dynamics. >> population dynamics are important especially since there's only about 720 mountain gorillas left in the wild. and they're smack-dab in one of the world's worst conflict zones, even the gorillas seem to know it. you're here in the congo border and there's obviously so much instability in congo, how does that impact the gorillas? >> the gorilla, they're pretty much obliged to stay in rwanda. they try several time to move her and to cross the border. and after a few hours, they run away. literally, they run away and

they come back here to rwanda. >> we've been here for an hour and kansbey and the others don't seem to mind our presence. frankly, they seem a little bored with us. we've been warned that these gorillas might be aggressive towards us because there's so many adult males in the group. veronica tells us it's been raining so much at night and it's been particularly cold so a lot of these mountain gorillas are exhausted and they're just kind of sleeping through the day. because gorillas can catch human diseases, scientists limit the time they spend with them. so after only an hour and a half, it's time for us to go. what we're doing is kind of look around the world, looking at places that man is in conflict

with nature and natural resources in animals. it seems like rwanda is a success story in many ways. >> yeah, yeah. definitely it is. there's still a lot of conflict but there's a lot of rwanda that they really care of the protection of gorillas. and this is i think the biggest success of conservation of mountain gorillas for people to take care of their own natural resources. >> this is a species still teetering on the brink. but rwanda's protection of these mountain gorillas is a lesson that conservation is possible. even on the battle lines. over the next 40 years the human population is expected to rise by 50%. already many of our natural resources are dwindling. recently, the u.s. director of national intelligence said that over the next 15 years or so, competition for the resources will likely lead to increased global conflict. the question governments around

the world have to answer now is how best to preserve the resources we have left through conservation and innovation and technology. if you of the more information go to cnn.com/planetinperil. i'm anderson cooper, thanks for watching this special of "planet in peril." ♪ [ male announcer ] let's kick our excuses to the curb. cover 'em up with an extra bag of mulch. let's get our hands a little busier.

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