Name __________________________________________ Period ______ Natural Selection and Evidence of Evolution Evolution is ___________________ in ______________________ characteristics over time. (Descent with modification) Before the 1800’s, few thought much about evolution. 1. Most people thought the Earth was only ____________ years old instead of _________ BILLION years old. 2. Few ___________________ to see similarities in species. 3. Many people accepted the ________________ story of creation. In the 1800’s, scientists started to change people’s minds…. Lamarck- A ___________________ scientist who proposed that traits developed during a parent’s lifetime would be _________________ on to their kids. Example: Giraffes stretch their neck to reach tall leaves, this results in a ____________ neck. This trait is then _________________ by the kids. Lamarck didn’t realize not all things are passed onto the offspring. (muscles, plastics surgery, etc.) Genetics wasn’t described until the 1860’s by_______________ Charles ___________________ - A _________________ scientist who studied nature and noticed similarities among animals. He concluded that all living things must be ________________________ and somehow they __________________________ or evolved over time due to natural selection. Natural Selection- An organism with the best _______________ for their environment is more likely to _________________________ and ___________________________. “Survival of the _______________________” How does Natural Selection Happen? (How do we get the “fittest” organism or the one with the best traits for its environment?) 1. Lots of _____________________________. (example_____________________) 2. __________________________ or variations occur in those offspring. 3. Some variations are _____________________, this results in a better chance of _____________________, reproduction, and passing on of those traits. 4. Over time, individuals with new variations may become a whole new ____________________. This is ____________________________. Adaptations are _____________________ that can make an organism better suited for its________________________. Adaptations can be _____________________ (on their body) or _________________________. Adaptations can help an organism….. Attract a ______________________, warn _______________________, _____________________ from predators (camouflage), or imitate a more dangerous animal ( ________________________) Geographic Isolation can allow some variations to ________________in a species that might have otherwise stayed hidden. Geographic Isolation Model Speed of Evolution Gradualism: A continuous series of _____________________ and variations which, over time will result in a new species. Punctuated Equilibrium: Rapid evolution that occurs when the mutation of a few ______________ results in the appearance of a new species over a relatively short period of time.