Moritz's Lab:

When Craig Moritz took the helm at Berkeley's Museum of Vertebrate Zoology seven years ago, he wanted to develop a flagship research project that would allow the university to address pressing 21st Century conservation issues, and honor the museum's long tradition of documenting California's species diversity. He envisioned a grand undertaking to which faculty and students could all contribute, regardless of their individual areas of expertise.

Lucky for Moritz, someone had already laid out a blueprint for just such a project nearly a hundred years before. Biologist Joseph Grinnell, the museum's first director and a prodigious collector of animal specimens, suggested in a 1910 paper that future scientists revisit his California fauna collection to find clues about how populations change over time.

The specimens, now housed in seemingly endless rows of metal cabinets in Berkeley's Museum of Vertebrate Zoology, are accompanied by sound recordings, drawings and painstaking notes about habitat, weather and fieldwork locations--so painstaking, in fact, that scientists are able to set traps and collect animals at the exact same spots where Grinnell worked during the last century. And that's exactly what professors and students are doing for the Grinnell Resurvey Project, now in its fifth field research season.

"It's not rocket science," Moritz says. "It's actually a really simple idea--go back and see what's changed, and then try to figure out why and how."

Data collected during the first three field seasons has yielded astonishing information about the effects of climate change on the distribution of species in Yosemite, a wilderness icon and one of America's most beloved national parks. The range of some small mammals, it turns out, has constricted considerably over the last century. Warmer temperatures have forced critters to seek cooler climes by moving uphill to higher elevations. But animals already living on mountaintops, like alpine chipmunks and bushy-tailed woodrats, have no place higher to go--they are running out of space.

"We're losing these high elevation species, and it really freaks me out a bit," says Moritz, a historical biogeographer whose fieldwork is concentrated in the wet tropics of his home continent, Australia. There, he has analyzed amphibians' genes to reconstruct the evolutionary pasts of present populations, work that required an understanding of past climates--and past climate change. So although he doesn't consider himself a climate scientist, Moritz's rare ability to take the long view and look back millions of years informs the way he thinks about what he calls the "climate change juggernaut that's coming at us."

To deal with climate change, we have to approach conservation differently than we have in the past, says Moritz. For example, the United States' strongest environmental protection law--the Endangered Species Act--is written to protect individual species and their habitats. That's a problem, Moritz says, because it means we end up protecting current diversity without simultaneously protecting the processes that produced that diversity: natural selection and evolution.

"It's not enough to circumscribe a certain area that captures a certain number of species that happen to be there," Moritz says. "Species are the outcome of a particular process. So if you're talking about conservation, should you just focus on the products or on the process that generate diversity? The answer is you want to do both. And I'd like to think that by better understanding biographic history, how speciation and extinction work together, we might be able to make better predictions given inevitably very sparse knowledge."

Recently, Moritz and a team of researchers used predictive techniques to identify the areas in California that seem to be promoting rapid evolution. "We simply asked, where are the geographic concentrations of young species?" Moritz says. Those areas, the team reasoned, will likely give rise to new diversity in the future, and should be conservation priorities now.

They analyzed molecular data from California's 25 endemic mammals to locate areas with high concentrations of "neoendemics," or young species. According to their results, the northern and central coasts, the Central Sierras, and the Tehachapi ranges all turned out to be evolution engines. But protecting these areas of potential diversification means protecting larger swaths of habitat, including low-elevation lands that are good for farming, Moritz argues.

"You've got to protect much broader landscapes," he says. "Connecting up protected areas will enable the sort of natural process of ranges' natural contraction and expansion and differential evolution to go on. Animals have to be able to migrate, and most of our pieces of protected area landscapes are really too small to allow this to happen."

Now, Moritz and his team are working to expand the analysis of the state's hotspots with data about California's amphibians and plants. Meanwhile, work proceeds in the southern hemisphere. Moritz has spent much of his career working in Australia's northeastern rainforests, trying to refine the effect of past global climate changes on the evolutionary histories of species and the resulting distribution of diversity.

A postdoctoral fellow, together with a graduate student in the Moritz lab are using some of these research techniques to look at Brazil's Atlantic rainforest--a system that, unlike most of Australia's tropical forests, largely lacks government protection.

"We found that there's an area in the northern Atlantic forest that was really stable through all these climate fluctuations in the late Pleistocene," Moritz says. In areas further south, models show that glacial cycles caused the rainforest to contract and survive only in little patches. Because ecosystem stability helps facilitate the generation and maintenance of species diversity, that suggests that Brazil's northern forests should be home to more endemic species and more genetic diversity overall than its southern tracts, despite the fact that the two regions look virtually indistinguishable to visitors today.

So far, data are showing that the hypothesis holds up, and the north is more diverse than the south. "But the northern area has hardly been studied using modern systematics, because they're relatively poor states," Moritz explains. "Much of the money and resources for conservation in Brazil are in the south. So we think it's fairly urgent to get in there, and use these models to try and predict which areas to go to, to discover new species and help local conservationists prioritize their efforts."

In addition to writing the grants that support the Grinnell Resurvey Project's expeditions and conducting research that's applicable to solving real-world conservation problems, Moritz also teaches evolution and molecular ecology--the part of his job ("the best job in the world," he says) that he counts as most important.

"The research is good, and that's useful and creative and I love doing it," he says, "but the long term impact is the students you train."

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