Life on Earth is disappearing, quite simply, because we're f*cking it up. How's that for a colorful quote?! Life is disappearing because on an individual level, we use a vast amount of resources and the human population has just been growing like crazy for the last 500 years. When you multiply lots of resource use by lots of people, you get a big problem in terms of the depletion of resources, pollution and global warming.

It's important that we maintain biodiversity for a couple reasons. One is the ethical reason - What right do we have to destroy the rest of the world? The other is a self-interested reason - biodiversity works for us.

A lot of medicines are made from wild plants, so when you destroy the tropical rainforests, you're destroying medicines that could be curing your cancer or saving your baby. That's just one example. If you take one species out, the whole system can collapse. It's not a question of which species matter; they all matter.

The Red List of Endangered Species came about because people, and scientists in particular, began to realize that animals were being threatened. The list was a means of giving the rest of the world the status of the wild animals and plants of the world in one centralized, compelling message.

The fact there are more and more species on this list every year is partly because our knowledge is increasing. We're finding new species all the time and getting new data about species in trouble. The other part of it is just that we're increasingly wiping species out because our rapacious use of the natural world is accelerating and more species will become extinct as a result.

Extinct means zero left. Critically endangered means it fits one of two criteria: Either there are very few animals left, or they're declining at a very rapid rate, so that in the near future, there would be very few left.

For the gorillas, we used the criterion that their population is declining very rapidly. That is, it would be declining by 80 per cent within three generations. There are still tens of thousands of western gorillas out there, but the decline rate is so fast that it was just staggering.

I'm not only drawn gorillas and chimpanzees; it's everything in the forest. You walk around the forest, turn a corner and suddenly there's this gorilla looking you in the eye, and you're looking at it. There's clear recognition there, and it's an extremely intelligent animal. It has the same emotions you and I have, it can remember things that happened in the past, it has a concept of the future, it mourns its dead, and it has very strong social bonds. Female gorillas will nurse their babies for five years.

They're just so much like you and me that it's just a crime to kill them-an absolute crime. A number of things are killing gorillas, but in Africa and other parts of the world, habitat loss is the huge issue. In this part of the world, it's not habitat loss, but hunting, poaching and Ebola virus.

Now, they're our closest relative in the animal kingdom and are like us in many ways, but gorillas are also different from humans. They don't hunt other animals. That's the biggest difference. Chimpanzees have sort of organized wars, and humans have organized wars, but gorillas don't. Also, gorillas aren't destroying the planet.

The biggest thing we're doing (but not doing enough) to reverse the trend of endangerment is anti-poaching law enforcement. In North America, that's the basis of all the politics. If you shoot a grizzly bear or a bald eagle, you'll be arrested. In the countries where gorillas live, they don't have established parks services to protect them. They're just developing their park systems and getting their anti-poaching going, and the problem is they don't have enough money.

Anti-poaching isn't sexy. People would rather give money toward sexy eco-tourism stuff or working with local villagers to develop alternative sources of protein. These are things that make a nice brochure, but actually aren't as effective as basic park management and, in particular, anti-poaching.

For some species it's already too late. For example, the Yangtze River dolphin - they thought it was extinct, and they recently just found one individual. Essentially, for that species, it's just too late. You can't bring it back when it's dwindled to one, and it's very sad.

The California condor is another one. It had dwindled to I think six individuals, and that was because people were shooting them. They had mistakenly thought they were predators that were eating sheep or something, but it turns out they don't eat sheep - they're scavengers, not predators. They were hunted to the brink of extinction for no good reason. Because some dedicated people did something about it, they were able to bring them back, and now they're making a slow recovery.

The most frustrating thing for me is that saving animals is really possible. It's not that much money involved. The political will is just not there. If people would just pay attention a little bit and maintain their relationship with these conservation projects, we could really do it. For instance, one of the biggest problems in any conservation is sustainable funding. You get a grant for three years, the grant dries up and then everything you were doing just falls apart.

The idea now is to have trust funds for particular parks, and you'll operate the park off the profits of the trust fund. The amount of money that would be involved in setting up a trust fund to protect five or ten thousand gorillas is about $20 million, which is the equivalent of four tanks in Iraq. If you didn't spend the money on tanks in Iraq and spent the money instead on protecting the parks, you'd protect five or ten thousand gorillas forever.

Humans have been waiting until it's too late, and not only that, they are also actively destroying the planet. Throughout evolutionary time, we have developed a system of prioritizing things and tend to focus on the thing that's right in front of us. As a consequence, we wait until the very last minute for conservation. When the condor is about to go extinct, we go, "Whoa, whoa, whoa," and then we act.

At a more general level, we wait until it's too late because people think Africa as a continent is just hopeless and they just don't want to get involved. The reality is if you have sustained involvement, you can effect change.

Mountain gorillas in Rwanda have been through two or three civil wars, but because particular people devoted to them, they have actually been increasing in number now. It is possible to succeed, but it takes sustained focus.

Speaking of people who have been devoted to gorillas, Jane Goodall is a goddess. Watching her films as a child was so inspiring. That being said, I don't think her current focus is the most productive focus. She's now focusing on sanctuaries for animals who have been orphaned or confiscated. I don't think that's the biggest concern. For most of Africa, the issue is all the tens of thousands of gorillas and chimpanzees that are dying from poachers and Ebola.

I have great respect for Jane Goodall, but the most important message is the anti-poaching, and it's got to get done NOW. The rate of decline is so great, that if we fool around for five or 10 more years, it's going to be too late. We'll still have gorillas and chimpanzees out there, but the population will be so small that it just won't be sustainable in the long run.

There are two things that are most positive. The one is just that seeing animals in the wild is mind-blowing. Walking around the forest among gorillas and chimpanzees is just the biggest high I've ever had in my life. It's amazing. I can't describe it.

The other thing is that through working on this Ebola work, I've gotten in contact with a lot of people from the biomedical community, and every single one of them is like a little kid. They get so excited when they think that they can possibly help. It's just great to deal with people who don't have any contact with apes in the wild, but who are so excited about doing something. It really gives me hope.