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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.
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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.com/watch?v=nVSJNhUhV-4 • Watch Second! • http://www.youtube.com/watch?v=gxeD65E_AvE • http://www.youtube.com/watch?v=0zHnhbW08yQ