Evolution How species change and how new species

Evolution: How species change and how new species are created • Why do species seem to be “molded” to their habitats? • Fossil evidence tells us that species change over time. Some species disappear (go extinct) and other species appear. How does this happen? • Why can the introduction of a new species into an ecosystem cause disruption?

Important Terms Evolution: All the changes that have transformed life on Earth from its earliest beginnings to the diversity that characterizes it today. Natural Selection: Process by which a particular beneficial gene or genes is reproduced more than other genes in succeeding generations. Biodiversity: Variety of different species.

Jellybean experiment Jellybeans are your favorite prey The following slide contains a forest filled with delicious jellybeans. See which ones you can capture in 5 seconds. Record how many of each color you can catch.

Jellybean forest

Results #Eaten: Blue Black Yellow Green

Implications Start Survivors (reproduction) Next Generation

Genetic variation There must be genetic variation in traits (characteristics) on which natural selection can operate. For jellybeans it could be color or ? ? ? versus

Example of the Peppered Moth

Example of natural selection: Changes in moth color due to changes in the color of tree trunks in England in the 19 th and 20 th centuries moths tree trunks pre-industrial tree trunks and moths post-industrial pollution controls