A team of 102 scientists spent a year surveying a small area of the San Lorenzo rain forest in Panama to count the number of species of arthropods living there. After collecting 129,494 specimens—using nets, traps, shovels, tree-climbing harnesses, helium balloons, and other creative gear—it took the team eight years to sort and identify the arthropods. By comparing the number of arthropod species that were common among the 12 plots sampled, the researchers estimated that the total number of arthropods in the whole San Lorenzo forest is 25,000 species. To come up with this estimate, what's one assumption the researchers had to make about the forest?

Verified step by step guidance

1. Step 1: Understand the problem. The question is asking for an assumption the researchers had to make to estimate the total number of arthropods in the whole San Lorenzo forest based on their survey of a small area.
2. Step 2: Consider the method used by the researchers. They surveyed a small area and then extrapolated their findings to the entire forest. This implies certain assumptions.
3. Step 3: Identify the first assumption. The researchers must have assumed that the small area they surveyed is representative of the entire forest. This means that the species diversity and population densities in the surveyed area are similar to those in the rest of the forest.
4. Step 4: Identify the second assumption. The researchers must have assumed that the sampling methods they used were able to capture all or most of the species present in the area. If some species were missed because they couldn't be captured by the methods used, the estimate would be too low.
5. Step 5: Identify the third assumption. The researchers must have assumed that the number of species doesn't change significantly over time. If the species diversity in the forest changes from year to year, the estimate based on a single year's survey might not be accurate.