In the 20th century, paleontologists such as [[George Gaylord Simpson]], [[Norman Newell]], [[Stephen Jay Gould]], and [[J. John Sepkoski, Jr.]] developed sophisticated mathematical techniques to analyze the fossil record of evolution and extinction, but they have been disputed among scientists. | In the 20th century, paleontologists such as [[George Gaylord Simpson]], [[Norman Newell]], [[Stephen Jay Gould]], and [[J. John Sepkoski, Jr.]] developed sophisticated mathematical techniques to analyze the fossil record of evolution and extinction, but they have been disputed among scientists. |