Evolution Evolution is the process of change over time Evolution occurs not only in living populations but in all sorts of other areas. Nintendo Super Nintendo Nintendo 64 Gamecube Wii Wii U
Theory of Evolution -NOT necessarily an explanation for the origin of life - Species are constantly changing. - Evidence for evolution comes from many fields of science
Evidence from Fossils Fossils allow us to view changes that have occurred in organisms over time (evolution) The oldest fossils are found at the bottom and the youngest are found at the top.
Evidence from Fossils The earliest organisms were small and simple in structure Over millions of years organisms became larger and more complex
Fossil Record The number of different types of organisms has increased over time Many species of organisms have disappeared and been replaced by different species
What’s so Humerus? • Homologous Structures • structures in different species that have the same structure but different functions
Checking 4 Understanding ___________allow us to view changes that have occurred in organisms over time. a. Evolution b. Fossils c. DNA d. Homologous Structures
Checking 4 Understanding • ___________structures in different species that have the same structure but different functions. a. Evolution c. Homologous Structures b. Fossils d. Vestigial Structures
Vestigial Structures Vestigial Structures - small incomplete structures / organs which have no apparent function [are useless] An analogy to help you… What is the purpose or function of the strap on back of some shoes?
Vestigial Structures Vestigial Structures - small incomplete structures / organs which have no apparent function [are useless] Real World Biological Examples: - Vestigial leg bones in snakes are evidence that the ancestors of snakes were reptiles with legs. - Vestigial pelvis bones in whales are evidence that their ancestors once walked on land
Checking 4 Understanding In the diagram of a whale below, the bones labeled "pelvis" and "femur" appear to be useless. Structures that do not appear to serve a function in modern organisms are called a. evolution b. fossils c. homologous d. vestigial structures
Biology Vocabulary Review 1. Evolution Fossil Fossil Record Homologous Structures Vestigial Structures / Organs