BIOLOGY 101 Study Guide - Final Guide: Exaptation, Plesiosaurus, Coelacanth
Document Summary
Differences in the concepts of time (physiological, geologic, etc. Physiological time: less than a second, a minute, hour, day, month. Ontogenetic time: year, decade, century, millennium, 10,000 years. Geologic time: million years, 10 my, 100 my, 1000 my. Relative time scale: based on the sequence of the geological layering of the rocks and the evolution of life. Radiometric time scale: based on natural radioactivity of chemical elements found in some rocks. More accurate, but can be affected by human error, is expensive. Different fields that all contribute to the history of life: petrology: type of rocks, stratigraphy: layer of rocks, paleontology: fossils. Igneous: rock formed through the solidification of molten magma (basalt) Sedimentary: buried continental material, deposition of strata, most fossils found here (sandstone) Mold fossils: a fossilized impression is made in substrate, a negative image of the organism. Cast fossils: formed when a mold is filled in. True form fossils: fossils of an actual animal or animal part.
