Which feature causes a gap in the geologic record? extrusion
fault
intrusion
erosion

What drives an advertising campaign?

Where does the information about where each transcription factor binds originate?

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.