NAN HAUSER

NAN HAUSER

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Whale Researcher
President of the Center for Cetacean Research & Conservation
Director, Cook Islands Whale Research

I don't think a lot of people realize how absolutely important whales are, and not just because they're beautiful and they make people happy, but whales carry nutrients from the depths they feed back to the surface. And there's this liquidy plume of fecal matter, and it's called the whale pump. And they bring all these nutrients upward with their tails by swimming up and down the water column, it's like an upward biological pump. And there's an incredible amount of nitrogen that's released in these plumes. And we get this great soup of nutrients. We get more from this nitrogen than all the rivers combined. And in the past, we recognized microbes and plankton and fish and that they recycled nutrients in the ocean, yet whales and other marine mammals have largely been overlooked and that's too bad because they are bioengineers. They help the climate so much because of all this creates more plankton by circulating the nutrients and fertilizing the phytoplankton with their poo.

MARK MASLIN

MARK MASLIN

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Author of How To Save Our Planet: The Facts
Professor of Earth System Science at University College London

I think the most important thing is realizing how much impact humans have had on the planet. For example, did you know that we move more rock and sediment than all the natural processes put together? We also have created enough concrete already to cover the whole world in a layer that's two millimeters thick, and that includes the oceans. We have also created and make something like 300 million tons of plastic every single year, which we know ends up in our rivers. It ends up in our oceans. And we've also found that microplastics have been found in human blood. So this is the impact we're having all around the world. We've also cut down 3 trillion trees, that's half the trees on the planet. We have doubled carbon dioxide in the atmosphere. We've increased methane by about 150%, which has led to a warming of the planet of about 1.2 degrees Celsius. And If you weigh the land mammals, 30% of that weight is us humans. There are 8 billion of us, and I have to say a few of us could lose a few pounds, but 67% of that weight is our livestock. And just 3% is those wild animals. So in less than 5,000 years, we've gone from 99% being wild animals to less than 3%. That's how much impact we humans have had on the planet.