Every gorilla will take a look at you, Purdy said. It actually only happens once. They kind of look at you a little bit like someone walking into a room.On the last day of his photo shoot, Purdy said, the gorillas started pulling branches effortlessly from trees. They meant no danger, instead they were showing off to see who was the strongest. Read more:25 award-winning photos of polar bears to help you celebrate International Polar Bear Day50 stunning wildlife photos that will make you see animals in a whole new light12 adorable photos of unlikely animal friends5 times animals masterfully photobombed proposals and engagement photosIt takes about two years of inhabitation, Purdy said. The silverback will look at him and go, 'Oh.' The next day he'll look at him and stay 10 seconds, 20 seconds. [The guide] builds that up over two years until the silverback is comfortable with people being around. This is the difference between animals that are potentially dangerous and animals that are dangerous. The difference is intent, Purdy said. A gorilla could just rip your limbs off, I mean literally just rip you to pieces. But when you're with gorillas, you never get the impression that's what they want to do. They're so gentle and so trusting.The males, one of them had died of natural causes, Purdy said. The other one had been chased away. Six new males had moved into the pride and killed all the cubs. I don't usually tell people, but every lion cub in the book apart from one — I call him Survivor — all the others were killed.Since then, Purdy said the Ridge Pride has thrived and that eight new cubs have been born: It's kind of the circle of life.The Ridge Pride were a really stable lion pride and they always kind of hung together, Purdy said. Prides can be quite spread out over large areas, but they always seemed to be together and really photogenic. Purdy had added Kevlar to the remote-controlled car for protection, forming a device similar to a makeshift bomb disposal robot that he called the G train. He had to take the doors off his safari vehicle to fit the device in the car. When he saw the group, Purdy decided to deploy the remote-controlled device, but the smell of the Kevlar alerted the lionesses. They were soon circling the safari vehicle like sharks. It was the only time ever I said to the driver, 'Look we need to go. We need to back up here. We need to give the cats a little bit of space because they're really not happy,' Purdy said. If you get within about 100 yards, they'll notice you and actively run back to the river or walk off, Purdy said. They won't let you get close.When Purdy noticed one grazing, he slowly drove the remote-controlled car closer and closer. Every time he was about to take a photo, the hippo would turn away from the camera, but right before it returned to the water, he was able to get a couple of shots. They kind of have a reputation for being some of the biggest killers in Africa, but that's when people used to use the rivers for transport, Purdy said. Basically when the hippo is in the water, it feels safe. If you paddle down the river in a boat, you're kind of threatening their safe space so they get quite aggressive. When they're out of the water grazing, they graze at night and go back into the rivers during the day, they're kind of like a fish out of water. They don't feel comfortable.It's actually an annual cycle, so with red deer, Purdy said. No matter what you do, it's basically only four months of the year that the male elk will be relaxed enough to tolerate any kind of camera in the vicinity of them.Purdy said he tried deer urine, deer scent, and deer food to draw them closer, but he eventually realized that it didn't matter what he did, the deer kept getting spooked. With animals like elephants, I noticed recently even on silent shutter we can't hear it, (it's actually a digital read-out of the sensor so nothing actually moves in the camera) but the elephants can hear it, Purdy said. So I need to wait until I get them right where I want them because as soon as they hear the camera, they get a little bit suspicious.Elephants are different because it depends on what kind of life they had with humans. Some of them have been in permanent conflict with humans, Purdy said. In some parts of Africa, they are very aggressive and if they see [someone] then they'll literally charge. Because they've been well protected where Purdy took photos, the elephants he encountered were peaceful. The buffalo is really, really grumpy, Purdy said. They'll attack lions. They'll attack cheetahs. They'll attack leopards. These are grass-eating animals. They're not going to eat them. They're just really grumpy.They charged my car on a regular basis, Purdy said. You couldn't get too close with the vehicle because they charge vehicles from time to time.People ask what is the most dangerous animal, and it may surprise people but the most dangerous is easily the buffalo, he said. Purdy said most local tribes know at least one person who was killed by a buffalo. When a buffalo sees you coming, they'll hide behind bushes and wait on you.Purdy refused to interfere with the mother and cub when they were hunting because he didn't want to put either in danger. The mother had three cubs, but two had been killed by a buffalo. After three days, Purdy found them while they were enjoying a stroll. For 90 minutes, Purdy took photos of the pair while they walked, sipped water from a creek, and rested. Neither mother nor cub cared about Purdy's nearby remote-controlled car. That was probably one of the rarest moments I had with my remote camera, Purdy said. They're quite placid. They're quite delicate, Purdy said. They're obviously speed demons and excellent hunters, but they don't climb well and they don't have a lot of endurance. They're in decline. If they're out hunting or walking, you don't want to disturb them.Developed by Sony for house pets like cats and dogs, the feature also did a remarkable job of focusing on the faces of lions and other animals like hyenas, Purdy said.It's a very slow, almost stealthy type of photography, Purdy told Insider. You can't go quickly, you can't race around. Animals just see that as threatening behavior or odd behavior.When the remote-controlled car is deployed near the animals, Purdy remains in a separate, safari vehicle nearby with a driver.Purdy has been capturing photos of Africa's wildlife for around 20 years. For his latest book, Purdy decided he wanted to try something different by getting as close as possible to his subjects. The book took him around 18 months and several trips to Africa to complete. Most of the images in the book were taken in Kenya and Uganda.