Lines of latitude measure north-south position between the poles. The equator is defined as 0 degrees, the North Pole is 90 degrees north, and the South Pole is 90 degrees south. Lines of latitude are all parallel to each other, thus they are often referred to as parallels. Your latitude can be calculated by measuring the angle of the sun.
Got this from google, scientists count a species population by first knowing the population in a certain area or small geographical sample location then multiply the result by the total area.
