Brownsville is a borough in Fayette County, Pennsylvania, United States, officially founded in 1785 located 35 miles (56 km) south of Pittsburgh along the Monongahela River.
2nd Item Specification: Given a group of organisms and a key, classify organisms based on observable characteristics. Depth of Knowledge Level 1. 1  A tool used by scientists to identify unknown organisms based on observable characteristics is called a. 2  dichotomous key.
Scientists mainly compare similarities and differences in what the organisms look like. With the less obvious relations, they analyze their DNA. The goal is to find a common ancestor between the two organisms. The more recently that ancestor existed, the more closely related the organisms are.