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Evolution in Action. Evolution In Action. Evolution is a continuous process that is happening all the time Many people have a hard time noticing this because how long it takes to happen. Evolution In Action. - PowerPoint PPT Presentation
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Evolution in Action
Evolution In Action
• Evolution is a continuous process that is happening all the time
• Many people have a hard time noticing this because how long it takes to happen
Evolution In Action
• If we look at individual species and their traits we can see how a species has evolved in the past
• We can also see how the trends in their current course of evolution
Anole Lizards
• A good example is the anole lizard species on the Islands in south east North America
• Among the many different types of anole lizards there many different body types and sizes
Anole Lizards
• There are several twig dwelling species of lizards on the islands
• All of these lizards have thin bodies, short legs and tails
• This allows the lizards to have an advantage in living in and hiding among twigs
Anole Lizards
• When scientists tested the DNA from each of these lizards on different islands they noticed they had different DNA
• This means that all of the lizards have different ancestors
• They came from different parent species!
Convergent & Divergent
• This means that the species of lizards on these different islands adapted to have similar traits
• They came to each island separately and adapted to living among the twigs on each island
• The most successful adaptations just happened to be similar on each island
Convergent & Divergent
• The process where different species evolve similar traits because of their environment is called convergent evolution
• This often happens in a similar environments where certain traits are more likely to allow a species to survive
Convergent & Divergent
• Along with the twig dwelling species there are also grass dwelling species, trunk dwelling species and leaf dwelling species
• All of these species have different characteristics
• Some have long legs, big feet or longer tails
Convergent & Divergent
• All of the different traits came about because of adaptations of the part of the environment lived
• Lizards with larger feet were better suited for the trees
• Lizards with longer legs were better suited for the ground
Convergent & Divergent
• Divergent evolution is a process where descendants of an ancestor adapt different traits to fit in their environment
• We see this with different species all over the world
Artificial Selection
• What is the process that Darwin proposed is the driving force behind evolution?
• Natural selection is a process that occurs in the natural world
• This means that no human can interfere
Artificial Selection
• Sometimes humans tamper with natural selection
• This can be seen most often in dogs
• Humans tend to want dogs with certain desirable traits
• They breed dogs together that have these traits
Artificial Selection
• Artificial selection is the process of humans selecting individual traits to give to the next generation
• It is the only way that we could have gotten one of these from one of these
Video
• Watch First!• http://www.youtube.co
m/watch?v=nVSJNhUhV-4
• Watch Second!• http://www.youtube.co
m/watch?v=gxeD65E_AvE
• http://www.youtube.com/watch?v=0zHnhbW08yQ