Graph It- Introduction to Graphing

1. How many bird species were observed in 1908?

2. How many bird species were observed in 1950?

Data—like that shown in this table—forms the core of all scientific inquiry. Scientists look for trends in data, then attempt to explain those trends. These possible explanations lead to new experiments, which then lead to new discoveries and new questions.

Scientists use graphs to make it easier to see trends in data. 

This graph is a line plot of the data set. Each point represents one row of the table. The connecting lines allow you to visualize the trend in the data.

Learn about each part of a graph.

The vertical axis along the left is called the Y-axis. Number of species is represented along this axis. 

The lowest value on the Y-axis is 0 and the highest value is 40. This range is called the Y-axis scale.

The point where the X and Y axes meet is called the origin. It is the smallest value a point can have on the graph for both axes.

The horizontal axis along the bottom is called the X-axis. Years are represented along this axis.

The lowest value on the X-axis is 1880 and the highest value is 2000. The range is called the X-axis scale.

Each point represents a single data row. You use the vertical and horizontal location to represent the values on the X and Y axis.

The data points are connected by lines that represent the sequence of the data—in this case, years.