Smithsonian National Museum of Natural History

Science Process

Process of Science

Did you learn science the old-fashioned way, with a textbook with a set of instructions for using equipment provided to do experiments to test hypotheses? The experiments had outcomes known to teachers and the people who wrote the textbook. If you followed the instructions well, you got to the right outcome. If you got the wrong outcome, you reasoned through what might have gone wrong.

How Science Starts

Real science does not look for known outcomes. Scientists choose to study things that they want to know more about. There are many starting points for the process of real science. Often, questions arise during research and lead to new research.

For example, Smithsonian researcher Dr. David Johnson studies remoras, fishes with sucking discs on their heads used to adhere to host fishes. By observing their development, he found that the sucking disc is a modified dorsal fin. Scientists have known for years that larval remora have large, hooked teeth on their lower jaws, but their function is unknown. During his research it occurred to Dave that the hooked teeth might allow the larva to live in the gill cavities of a host fish, hanging onto the gills until its disc is fully developed.

Where Science Happens

While the image of a scientist in a white coat working in a laboratory is familiar, much of science is conducted in other settings.

For example, Smithsonian Paleobiologist Dr. Bill DiMichele conducts his science in coal mines. Because coal is made from 300-million-year-old plant material, it is a great source for fossil remains of plants. Bill capitalizes on mining operations that expose ancient layers of coal. With colleagues from the Illinois State Geological Survey and the Peabody Coal Company, Bill discovered the world’s oldest known tropical rainforests in the ceiling of a coal mine.

Where Science Leads

While real science may include the testing of hypotheses through experimentation using tools, the process of real science is often nonlinear. Research leads in unexpected directions and can yield surprising results.

Former Smithsonian zoologist Dr. Kristofer Helgen set out to study small South American mammals called olingos (genus Bassaricyon). While examining museum specimens and their historic data, he noticed sets of specimens that looked different. The specimens had smaller teeth, denser fur, and a higher altitude distribution than other olingos. DNA analysis confirmed that they belonged to a distinct species (Bassaricyon neblina), new to science, which he named "olinguitos." Kristofer and a team of colleagues, including an Ecuadorian zoologist, found olinguitos in the high Andes mountains, and began work to learn as much as they can about them.

Filling in the Gaps

The data collected from science is gradually assembled over time to tell an evidence-based story about how the world works. A key piece of scientific work may fill in gaps in the story.

Scientists had long known that the oldest known dinosaurs were upright, running on their two hind legs and preying on other animals. But they weren’t sure how those early "theropod" dinosaurs were related to species that appear much later in the fossil record. Then, a team of Smithsonian scientists led by Dr. Hans Sues discovered a new species of dinosaur in New Mexico. Named Daemonosaurus chauliodus, the structure of its neck and other features pegged it as an evolutionary link between the early and later theropod dinosaurs.

New Views of Old Data

Science always includes collecting evidence; for example, observations of organisms, outcomes of experiments, or results of genetic analyses. However, scientists may not collect new data, but instead look at old data in new ways.

For example, a team of Paleobiologists, including Smithsonian’s Dr. Gene Hunt and Dr. Matthew Carrano, put an old theory to the test by combining data in new ways. Cope’s Rule states that animal body sizes get bigger over evolutionary time. Usually applied to mammals, the team set out to test whether the rule applied to dinosaurs as well. Using measurements of thigh bones, they discovered that some lineages of dinosaurs, such as hadrosaurs, got bigger over time, but others did not. Theropods, the lineage including T. rex, grew very large, but reached an upper limit beyond which they may not have been able to support their bodies on two legs.

Science Takes Time

Significant scientific findings may take decades, lifetimes, or more. Good science is grounded in repeat observations, multiple lines of corroborating evidence, and peer review.

For example, the late Smithsonian Anthropologist Dr. Dennis Stanford analyzed early stone tools from the eastern United States (Clovis tools). The conventional theory is that the earliest inhabitants of North America were Asians who crossed the Bering Strait. What Dennis found, based on the workmanship of 12,000-year-old spear points, was evidence that earlier inhabitants arrived from Europe. His findings were rejected by colleagues in 1999 when first announced. Additional evidence he gathered over nearly 15 years has convinced many colleagues, although the origins of the earliest North Americans continue to be debated.

Evolving Techniques

Scientific knowledge evolves as new data is collected and new techniques allow data to be gathered and processed differently.

Scientists had traditionally believed that ostriches were closely related to emus and other flightless birds. DNA sequencing techniques allowed Smithsonian’s Dr. Michael Braun to take a modern look at the relationships among flightless birds. He was surprised to find that some flightless birds are closely related to flying birds called tinamous and that ostriches are not closely related to other flightless birds. The research raised the new question of whether flightless birds evolved from flying birds or the reverse.

Erratic but Essential

So, the process of science cannot be summed up with a science manual because science takes many pathways. The what, how, when, why, and where make every scientific study unique. The information that results from a study may disappoint or exceed expectations, depending on what happens along the way. Scientific studies are journeys of discovery, united by their common focus on gathering evidence and exploring what it reveals about our world. Good science is grounded in reliable evidence and conclusions that have been vetted with credible scientific peers. 


Resource Type
Science Literacy Articles
Grade Level
Life Science