Day 7 Evolution
EVOLUTION!
-The word evolution means change over time.
-We can apply this to anything. We can say that a band or musician's career has evolved. This does not mean that it got better it just means that it has changed over time.
EVERYTHING CHANGES
-In biology, evolution means change of allele frequencies over time. Think of this as a change in genes over time
In order to pass on your genes you need to reproduce. Evolution is all about who reproduces
-The four mechanisms of evolution refer to who chooses who gets to reproduce
The four mechanisms of evolution
Natural Selection
-Is when nature chooses who gets to reproduce
-Survival of the fittest
Artificial Selection
-Humans choose who gets to reproduce
-How we turned wolves into Chihuahuas
Sexual Selection
-The opposite sex chooses who gets to reproduce
-Usually goes against natural selection
-A peacock's feathers and a frog's croak are good examples
Watch this video on evolution. (Online Course instructions only) Create a box in your sketchbook, title it "Evolution" and take notes, write down the definitions and explanations in your own words and include an image in your sketchbook.
Genetic Drift
-This is the only one that is not a selection
-It is usually an accident
-You reproduce with what you have because they are the only options
-The only ones in an area (Founder Effect) or a disaster kills off most of the group (Bottle Neck effect)
Speciation
-Speciation is when one species turns into another species.
-Speciation uses evolution to describe its process.
-Usually one species branches into two species. From that point one of the species could go extinct or both can continue to survive.
History of life
-The first cell hypothesis is the hypothesis that one cell turned into all life on earth. This is a hypothesis that uses evolution to describe how it happened.
Evolutionary Structures
Watch this short video on evolutionary structures. (Online Course instructions only) Create a box in your sketchbook, title it "Evolutionary Structures" and take notes, write down the definitions and explanations in your own words and include an image in your sketchbook.
Homologous Structures
Analogous Structures
Vestigial Structures
