Grand Prismatic Spring
Grand Prismatic Spring is a highlight of the park, colored by microorganisms.

Yellowstone National Park

Yellowstone was the first national park in the world, created in 1872. It existed as a national park for 44 years before there was even a National Park Service. So it is fitting that it should be the focal point of the first Experiencing Life trip.

Yellowstone is probably most well known for its geysers and other geothermal features, such as Old Faithful. The majority of the world's geysers are found within the park boundaries. The existence of the geysers is due to the fact that Yellowstone is located above a geological "hot spot," where the magma under the earth's crust comes closer to the surface than usual in the middle of a continent. The word Yellowstone comes from the yellow sulfur deposits found in the Grand Canyon of the Yellowstone.

Another unique feature of the park is associated with its hot springs, but is not a geological phenomenon. Instead, this feature is biological. A group of microorganisms, similar in some ways to bacteria, but very different in some ways, is found in abundance in these environments which would kill most living things. The name of this domain of life is Archaea. This domain is generally made up of extremophiles, such as those organisms that can live in extremely salty or acidic environments. The domain also includes organisms called thermophiles that can withstand temperatures approaching, and even exceeding, the boiling point of water. These types of organisms are found all over Yellowstone, and are the cause of the brilliant colors found in the picture above.

The park is also home to many of the continent's large mammal species, such as bears, bison, cougars, elk, and wolves. It is also the place to experience the lodgepole pine forest type.

Our introductory video about the park

There is so much that can be experienced in Yellowstone that the problem becomes making a decision about how to narrow down the focus, at least for the biology aspect of the trip. Because no place else really has the extreme environments that Yellowstone has, it makes sense to focus on the organisms that can live in these environments. Whether hot or acidic or whatever, only very specialized microorganisms can live in some of the hydrothermal features of Yellowstone. Since microorganisms are often single-celled, it makes sense to make sure we're all on the same page about what defines a cell and what some of the differences are from cell to cell. To understand one of the fundamental things that defines a cell, the cell membrane, it is helpful to understand the molecules that make up this outer barrier of a cell. Molecules are made up of various elements, or atoms, and the way atoms interact defines the properties of molecules like the ones that make up the cell membrane. There are many other parts of cells but a membrane is common to all cells, so this is the only part we will focus on in detail in this trip.

To summarize things to this point, one major focus in Trip 1 is on cells. We'll get into a little diversity of cell types and the way different cells can handle different environments. And we'll focus on some chemistry so that we can understand better why cell membranes do what they do.

Another major focus is on taxonomy and systematics. Taxonomy is the process of classifying organisms into groups like "plants" and "animals". As bird-watchers know, part of the joy of experiencing life comes from seeing something rare and knowing it. This whole series of trips is rooted in that fundamental belief. But we will move well beyond bird-watching to "life-watching"! Part of the focus of Trip 1 will be on learning how to talk about the wide variety of living things and how they are related so you can eventually know when you see something rare.

Systematics is a specific method of classifying organisms, based on their evolutionary relationships. To contrast the two terms, I'll give an example using three organisms: a tuna, a dolphin and a deer. If we were not concerned with evolutionary relationships, one taxonomic system might put the whale and the tuna into one group containing animals that live in water and cannot travel on land. The deer would be in the land animal group. This would be one form of taxonomic system, and there is a logic to it. But today, the accepted classification systems are based on systematics and evolutionary relationships. So, back to our example, we know that whales have lungs and mammary glands for feeding their young and bones hidden inside their bodies that are similar to the hips of mammals. Evolutionarily, they are much more like the deer than the tuna, so the fish would be the one in a group by itself (fishes) and the whale and deer end up together in a group called mammals. Not all scientists agree on exactly how organisms are related but most agree on using an evolutionary basis for creating the groups.

Tallying things to this point, we will focus on cells, chemistry, organisms that live in extreme environments, taxonomy and systematics in Trip 1, especially Yellowstone. And that's already a lot! But there are a few more things on which to focus in Yellowstone.

With so many different kinds of mammals in Yellowstone, it just makes sense to focus on them. This will be a good way to apply what we learn about taxonomy and systematics while learning more about the class of organisms to which we, as humans, belong.

In addition to experiencing rare organisms, it can be just as exciting to experience different kinds of environments. Trip 1, and Yellowstone itself, will not expose you to very many kinds of environments, but we'll begin to discuss the concepts of environments, ecosystems and biomes here. The name of this trip is "Greater Yellowstone", which refers to the greater Yellowstone ecosystem, so we'd better have at least some idea of what that means.

This brings us to the last focus of Yellowstone: scales. Since the organic topics for Yellowstone range from atoms to molecules to cells to large mammals to ecosystems and biomes, it just makes sense to try to put the scales of these topics in perspective. We'll stop at the scale of Earth in Trip 1 and carry things upward in Trip 9, when outer space is a topic.

Cells, chemistry, very small organisms, very large organisms, how organisms are classified and the environments in which they live. That sums up Yellowstone and Trip 1. On your visit to Yellowstone, you will likely see birds and fish and wildflowers and tree upon tree and many other fascinating organisms, but those will be focus topics of other trips. To explain why Yellowstone has the geysers and hot springs that it has will require a little geology (see video below), but geology will be a focus of another trip as well. Trip 1 gets us started with some of the basics so you can better-appreciate the experiences you have on this and those following trips.

One of the videos about the park's thermal ecosystems.
Other NPS videos


Trip Menu
  1. Greater Yellowstone
    1. Wind River Range
    2. Yellowstone National Park
    3. Wasatch-Cache National Forest
    4. Great Salt Lake
  2. Southeast
  3. Northeast
  4. Four Corners
  5. Northwest
  6. Heartland
  7. California
  8. Great Lakes
  9. Southwest
  10. Mid-Atlantic
  11. Alaska
  12. Hawaii
Northwest Wyoming

Yellowstone Map


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