As species of living things change over time, the DNA contained in their cells change, because of evolution. If we can extract the information from living things today, and compare them to each other, we can see which living things are most closely related, the most similar can be thought to be the most closely related in time. Biologists can then construct family trees, or phylogenies. By combining each tree, a grand tree connecting all living things can be made, this is called the "Tree of Life". Bioinformatics uses integration of mathematical, statistical and computational method to analyze biological, biochemical and biophysical data.