 When I was about four, we traveled across the mighty Pacific to New York and there I was introduced to dinosaurs. They impressed me, but what impressed me more is the fact that the world changes sometimes radically. Fast forward about half a century and here I am now at Berkeley in my dream job, custodian of some six million fossils including T-Rex. The missions of the Berkeley Natural History Museum is to understand life and the forces that have shaped it. I'm going to give you a sense of the way that operates. Here is a piece of Middle California taken in 2013. What did it look like 70 years ago? More trees just the same? With the historical record we know what the answer actually is. So the museums and our communities have been mapping the world. This next slide shows you one of those maps. This is now vegetation cover in Central California centered around Lake Tahoe. The dark green is Juniper and Douglas Fir. Again if we go back 70 years what did it look like? It turns out that forest was predominantly pinion pine in the light green changed from the dark green. Change is hard to comprehend in part because it's the spatial scale that's much more than our individual senses can pick up and also because change is slow. But there are two other reasons that make change difficult to comprehend. The first is the way we grow up. We grow up well with a platform of stability. We are not well suited to dealing with instability. That's the first reason. The second one is that we are highly adaptable. We get used to change particularly if it's slow. I want to give you an example. I grew up in the land of fire. That land is large about the size of the lower 48 states. It also has a predominance of fire. But we get used to it in Australia and so here are some cricket players barely paying attention to the blaze that's raging in the background. We get used to the way the world is. Now the historical record has shown us that we have changed the world irreversibly in the past. Here is a picture of California about 13,000 years ago and at about that time a species arrived. Us driving all of those species to extinction as we simply looked after our family, our children. The same thing happened in Australia about 50,000 years ago where the natives wiped out 10-foot kangaroos and wombats the size of small elephants. Now what's interesting in Australia is this occurred over about 5,000 years. Without museums, without historical records, they could not have known that they were driving these species to extinction. So what I want to do now is turn to the historical record of the two primary drivers of global change, population increase and carbon emissions. The data on population increase are really interesting. The upswing occurred quite recently in the 1950s and we see the impact of it again with historical record, for example, with the deforestation of the massive island of Borneo starting again in about the 1950s. CO2 emissions is also very interesting. This is the CO2 emissions of the world at about the time of the American Revolutionary War, just the UK. This is the time of the defeat of Napoleon at Waterloo. This is during the American Civil War. This is at the end of World War I, World War II and about a decade ago. So it turns out that the emissions and the population growth and the resource extraction has really been basically within my lifetime. Now, I experience the world as being fundamentally stable and yet viewed globally, it's been fundamentally unstable in my lifetime. And so rather than being stable, it's very much like the globe is like this poor whale from Hitchhiker's Guide to the Galaxy that was blinked in probably into existence high in the atmosphere. We are in freefall. What is exciting for me being at Berkeley, apart from my six million fossils, is the incredibly rich community of scholars, postdoc students with rich partnerships with industry, government organizations, NGOs, making a difference in the world, retarding that fall. And we've seen some very nice examples of that. For example, the Berkeley-innovated cook stoves in Africa or at larger-scale technologies that lead to solar farms that can supply energy for whole communities. At present, the world is giving us lemons. But here at Berkeley, we're really good at making lemonade. Thank you.