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