(Describer) Streams of light collide to create a globe filled with water. Title: Science Nation. Vehicles head down a road between sand dunes with tufts of green on them.

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(narrator) It's 6:00 AM. Bree Rosenblum and her team are headed to do some fishing.

(Rosenblum) I like to use the slip knot in the slip knot.

(narrator) Don't let the dunes or fishing poles fool you. This is no beach. This is the desert. Want to get a GPS point?

(narrator) With support from the National Science Foundation, biologists from the University of California, Berkeley, are at the White Sands National Monument in New Mexico to study evolution in action. These lizards tell have a story about how new species form. Hey, hey, hey, hey, hey, hey.

(Describer) Two lizards she holds try to squirm away.

Hey! Hang on. Hang on!

(Rosenblum) We're interested in biology questions. It's exciting in this time when our world is changing really rapidly and we want to know whether and how and when animals will be able to adapt to environmental changes.

(Describer) The sun is low over the desert.

(narrator) They come to White Sands because it's an evolutionary hotbed. The 275-square-mile gypsum dune field formed very recently, geologically speaking-- only about 10,000 years ago.

(Rosenblum) The animals that colonized this area went through an incredible amount of change to live in this unique environment. We see a lot of the animals have evolved a number of adaptations to survive here. The most noticeable one is that they're all incredibly light in color.

(narrator) These are whiptails, one of the lizards they study. They are the same species, but may be diverging into two. The guy on the left was caught here on the dunes. The White Sands one is a lot lighter than the one from down the road. Its stripes on its back are much fainter.

(Describer) She catches them with loops on a pole.

(narrator) The team also studies lizards in nearby transitional zones where white sand gradually gives way to brown. These so-called "fence lizards" are climbers-- they like trees, and running along ridges.

(Rosenblum) We measure their color, different aspects of their body size, what they're eating.

(narrator) They take a tissue sample, usually from the tail tip, back to the lab for genetic analysis.

(Rosenblum) The same gene involved in the color difference in these lizards is also a gene that's involved in color variation even in humans.

(narrator) Rosenblum says lighter-colored lizards have a better shot than darker ones at living long enough on the white sands to breed and pass on genes. They even select mates based on color. They must be camouflaged in their environment because they are out looking for food and looking for mates and doing things lizards do. And their predators are out looking for food and all the things that predators do during the day.

(Describer) She kisses one of them.

Love you, puppy.

(narrator) She says understanding the process of evolution is important, given the large number of species facing extinction around the world today. Some won't make it, but some will, in part, by adapting quickly-- a lot like these lizards.

(Rosenblum) In this time where things are changing so rapidly-- how can we give species the best chance at survival? Part of that story is evolution. It has to be. The world is changing too quickly for species to survive without evolving.

(Describer) She sits with her team.

(narrator) Sunset and twilight. A good day's fishing for these folks, even though they only caught little ones.

(Describer) The globe turns.

For Science Nation, I'm Miles O'Brien.