HAPPY WEDNESDAY Explain in 32 words what is happening in this PEDIGREE comparing long-necked...
-
Upload
reagan-force -
Category
Documents
-
view
237 -
download
1
Transcript of HAPPY WEDNESDAY Explain in 32 words what is happening in this PEDIGREE comparing long-necked...
HAPPY WEDNESDAY Explain in 32 words what is happening in this PEDIGREE comparing long-necked giraffes vs short-necked giraffes.
Essential Question: How do evolutionary mechanisms other than
natural selection affect adaptation and diversity?
Standard 7F: Analyze and evaluate effects of other evolutionary mechanisms.
It is widely accepted that the first living things on Earth were prokaryotic cells (bacteria). How did prokaryotic cells turn into eukaryotic ones?
The answer is The Endosymbiotic Theory.
K. The Endosymbiotic Theory is the theory that eukaryotic cells formed from a symbiosis (two
organisms live together) among several different prokaryotic organisms.
• Sometimes organisms that are closely connected to one another by ecological interactions evolve together.
• An evolutionary change in one organism may also be followed by a corresponding change in another organism.
• The process by which two species evolve in response to changes in each other over time is called coevolutioncoevolution.
Co-evolution
• Mimicry occurs when one organism evolves to look like the other in order to benefit itself. The mimic benefits from the situation while the organism it mimics in unaffected.
Example:Example: Orchid flowers that mimic female wasps
Mimicry is another example of coevolution
• Convergent evolution describes evolution toward similar traits in unrelated species.
• When two species are similar in a particular characteristic, it’s only convergent evolution if their ancestors were not similar
Convergent Evolution
• Divergent evolution describes evolution toward different traits in closely related species.
• Divergent evolution can lead to speciation.
kit fox
ancestor
red fox
Mix-Freeze-Group
• I am going to survive! Because I have the best genes for my environment.
• I am HUGELY affected by genetic drift.• I am VERY picky. I will only choose you, because your traits
are most attractive to me.• I am a mistake in the DNA sequence
Natural Selection
SmallPopulation
GeneticMutation
Non-RandomMating
1. Amish people are required by their religion to only marry and have children with other Amish people.
2. The DNA sequence in a bird is changed from ATT CCG TTG to TTA CCG TTG which changes the beak shape from long and thin to short and fat.
3. Peppered moths are eaten by birds. The moth color varies from light to dark. Light colored moths can blend in with a nearby species of tree. In the 1800s factories released large amounts of soot, which changed the tree color, so the birds were able to more easily find the lighter moths instead of the darker moths.
4. Northern elephant seals were hunted almost to extinction by people in the 1890s. The remaining population has reduced genetic variation.
6. A small group of birds flies from the mainland to an island and starts a new colony. (The birds never return to the mainland.)
WHICH PATTERN IS IT? coevolution convergent evolution divergent evolution
divergent evolution
The Galápagos finches evolved through natural selection from a common ancestor into a wide variety of different looking species with different kinds of beaks
http://images.encarta.msn.com/xrefmedia/aencmed/targets/illus/ilt/T014608A.gif
WHICH PATTERN IS IT? coevolution convergent evolution divergent evolution
coevolution
Hummingbirds have a beak just the right length to reach the nectar in a cardinal flower and as they feed their foreheads bump into the pollen structure. Cardinal flowers are red which hummingbirds can see, but bees can’t, and their pollen structure is at just the right height forthe hummingbird to pick up pollen as it feeds.
WHICH PATTERN IS IT? coevolution convergent evolution divergent evolution
Convergent evolution
Whales, sharks, and penguins all have streamlined bodies and fins/flipper for moving in water even though they belong in different animal groups (mammals, fish, and birds)
WHICH PATTERN IS IT? coevolution convergent evolution divergent evolution
divergent evolution
Beaver in North America and capybara in South America are closely related species living in very differentenvironments that have evolved to look differentover time.
Beaver
NORTH AMERICA
Muskrat
CapybaraSOUTH AMERICA
Coypu
Beaver
Muskrat
Beaver andMuskrat
Coypu
BIOLOGY by Miller and Levine Pearson Publishing