Evolution :Evolution Chapter 13 How did this star-nosed mole develop such a well-adapted nose? The answer awaits!


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution Evolution is a theory True- highly probable explanation, has a lot of evidence, not disproven Evolution is something you should believe in, like a faith. False- Should not believe in it, it is based on science 3. Evolution is concerned with how life originated False- Is not concerned with how life was first placed here.


But its just a theory. :But its just a theory. http://www.pbs.org/wgbh/evolution/library/11/2/e_s_1.html How does the scientific meaning of a term like theory differ from the way it is used in everyday life?


: Evolution is a science, something to support or not support. Not something to believe in.


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 4. Evolution is not just concerned with humans, it focuses on how all species change over time. True 5. Evolution was first explained by Charles Darwin False 6. Evolution is not the same as natural selection True- natural selection deals with how evolution can take place


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 7. Evolution is still occurring today True 8. Evolution happens to populations not to individuals True 9. Evolution is influenced by changes in the environment True- Environment is the major factor of why organisms evolve


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 10. Evolution was developed to undermine religion False- developed to explain observations of life in a testable way 11. Evolution denies the existence of God False- it is neutral, God is neither required nor eliminated, your choice based on your beliefs 12. Evolution conflicts with religions False- many religions support it.


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 13. There is no observed evidence against evolution True 14. Most religious groups support evolution True- most religious doctrines support evolution 15. Natural Selection causes bacteria to become resistant to antibiotics. True


Religion and Evolution :Religion and Evolution Two totally different things You do not have to pick between one or the other. There are many scientists who are very religious http://www.colbertnation.com/the-colbert-report-videos/173859/june-16-2008/kenneth-miller Colbert Report


Quote from United Presbyterian Church (1982) :Quote from United Presbyterian Church (1982) “ The imposition of a fundamentalist viewpoint about the interpretation of Biblical literature… is in conflict with the perspective on Biblical interpretation characteristically maintained by Biblical scholars and theological schools in the mainstream Protestanism, Roman Catholicism and Judiasm. Such scholars find that the scientific theory of evolution does not conflict with their interpretation of the origin of life found in Biblical literature.” http://www.ncseweb.org/resources/articles/4650_statements_from_religious_orga_3_13_2001.asp#rom


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 16. Humans came from monkeys False- we are related, came from a common ancestor 17. Charles Darwin proposed the theory of natural selection True 18. Natural selection says that individuals best suited to survive and do well in their environment will produce the most offspring True


Ladder vs. Tree :Ladder vs. Tree


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 19. A human’s arm and a penguin’s wing are made of the same type of bones True- Homologous Structures 20. The fossil record does not support evolution False- offers the most support 21. Radiometric dating allows scientists to date fossils True


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 22. Evolution refers to the changes in a population that occur over time True 23. Not all species are related False- we all share a common ancestor 24. Modern Humans evolved 5 million years ago False- 100,000 years ago


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 25. The evolution of one species does not affect the evolution of another species False 26. Extinction is a natural part of life True- just happening at a much faster rate today 27. Evolution does not affect me False- antibiotic resistance


Relevance to you :Relevance to you Understanding how diseases evolve helps us administer vaccines most effectively. Understanding the evolution of insects helps us devise more effective methods of pest control.


Let’s See What you Know about Evolution :Let’s See What you Know about Evolution 28. Insects are the most abundant animals because they are able to adapt/evolve to different environments True- insects live on every continent in the world 29. A good example of natural selection is found in tuberculosis. True- deadliest infectious disease because it mutates readily 30. Evolution is based on scientific exploration, not beliefs True- based on evidence


What is Evolution :What is Evolution Definition: How organisms change over time. The central ideas of evolution are that life has a history—it has changed over time—and that different species share common ancestors.


Family Tree :Family Tree


Slide 20:Who was the first person to propose the idea that life evolves and when did he live? Lucretius 2000 years ago


Darwin proposed a Mechanism for Evolution :Darwin proposed a Mechanism for Evolution What did Darwin get asked to do in 1831? To go on a voyage on the HMS Beagle as a naturalist


Map of Darwin’s Voyage :Map of Darwin’s Voyage


Science Before Darwin’s Voyage :Science Before Darwin’s Voyage In Darwin’s time what was the view of most people in regards to how life developed? Each species is a divine creation that exists, unchanging, as it was originally created.


Science Before Darwin’s Voyage :Science Before Darwin’s Voyage What was Jean Baptiste Lamark’s hypothesis (what did he believe)? Believed that over the lifetime of an individual, physical features increase in size because of use or reduce in size because of disuse.


Darwin’s Observations- Trip on the Beagle :Darwin’s Observations- Trip on the Beagle What did Darwin find in South America? Found fossils of extinct armadillos Looked like armadillos except they were much larger


Slide 27:Glyptodont Armadillo


Darwin’s Observations- Trip on the Beagle :Darwin’s Observations- Trip on the Beagle Where are the Galapagos Islands? 1,000 kilometers off the coast of South America


Slide 29:What did he find in the Galapagos Islands? Plants and animals that resembled ones on the nearby coast of South America Finches Iguanas Tortoises


Slide 31:Saddle-backed tortoises have a high shell allowing them to stretch their long necks. Found on islands were vegetation is higher. Saddle-back Saddle-back Domed tortoises have short necks and legs and live in areas with low vegetation. Domed


Slide 32:Pinta IslandIntermediate shell Pinta Isabela Island Dome-shaped shell Hood Island Saddle-backed shell Hood Floreana Santa Fe Santa Cruz James Marchena Fernandina Isabela Tower Giant Tortoises of the Galápagos Islands


Slide 33:Iguanas that swim and eat algae- only ones in the world


Artificial Selection :Artificial Selection Darwin noticed a lot of variation in domesticated plants and animals. Artificial selection :process by which humans select traits through selective breeding.


Ex. Pigeons have been breed for particular traits for 1000s of years :Ex. Pigeons have been breed for particular traits for 1000s of years Fantails are bred to have many tail feathers Croppers are bred for their inflatable crop. Jacobins are bred for their reversed neck feathers fantails Croppers Jacobins


Farmers have cultivated all the following vegetables from the wild mustard plant :Farmers have cultivated all the following vegetables from the wild mustard plant


Artificial Selection- Dogs :Artificial Selection- Dogs


Growth of Populations :Growth of Populations What did Thomas Malthus write about in 1798? Explain. Human populations are able to grow faster than their food supply.


Growth of Populations :Growth of Populations Population: consists of all the individuals of a species that live in a specific area and can interbreed


Evolution by Natural Selection :Evolution by Natural Selection What was Darwin’s theory of natural selection? Individuals that are better suited for their environment will survive and reproduce Katydid


Which would you eat? :Which would you eat? 1. Shield Bug 2. phyllium pulchrifolium


Find the Moths :Find the Moths


Evolution by Natural Selection :Evolution by Natural Selection Adaptation: is a feature that allows an organism to better survive in its environment


Publication of Darwin’s Work :Publication of Darwin’s Work Who persuaded Darwin to publish his essay and why? What was his essay called? He was persuaded to publish after he received a letter from Alfred Wallace that asked Darwin to help him publish his essay on Natural Selection. The Origin of Species


The Origin of Species :The Origin of Species There is grandeur in this view of life; with its several powers having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most wonderful and most beautiful have been, and are being evolved.


Darwin’s Theory- 4 main principles :Darwin’s Theory- 4 main principles Variation, exists within genes of a species Overproduction: many offspring are produced, not all will survive based on competition Adaptation: those that are better adapted will survive Descent with modification: over time species that are better suited for the environment will pass on their traits and the traits will become more common in the population.


How Natural Selection brings on evolution! :How Natural Selection brings on evolution! Individuals that are best suited to survive and do well in their environment will produce the most offspring. Natural selection causes the frequency of certain forms of genes to increase or decrease over time.


Natural selection acts on existing variation. :Natural selection can act only on traits that already exist. Structures take on new functions in addition to their original function. Natural selection acts on existing variation. A panda’s wrist bone also functions like a thumb


What does “survival of the fittest” mean? :What does “survival of the fittest” mean? Organisms best suited (strongest, most adaptable) will survive.


Species Formation :Species Formation Reproductive Isolation: condition in which two populations of the same species do not breed with each other because of geographic separation. As two isolated populations of the same species become more different over time, they eventually become unable to breed with one another.


Give an example of reproductive isolation in action. :Give an example of reproductive isolation in action. Kaibab squirrel- North Rim Grand Canyon, black belly Abert squirrel- South Rim grand Canyon, white belly Because they are isolated scientists call them separate species.


Slide 53:Kaibab Squirrel Abert Squirrel


The Tempo of Evolution :The Tempo of Evolution Gradualism: gradual change over time that leads to species formation


The Tempo of Evolution :The Tempo of Evolution Punctuated Equilibrium: periods of rapid change in species are separated by periods of little or no change


Beginning Question for Section 2 :Beginning Question for Section 2 Try to identify the pictures of different fossils. Write down the number and beside it what organism you think it is.


Slide 57:Mammoth


Slide 58:Fish


Slide 59:Nautilus


Evidence for Evolution :Evidence for Evolution Evidence for Evolution is found in five main areas 1. Fossil Record 2. Geographic Distribution of Living Species 3. Anatomy 4. Embryology 5. DNA


Fossil Record :Fossil Record Fossil: remains of a once living thing http://www.pbs.org/wgbh/evolution/library/04/3/l_043_01.html Fossils offer the most direct evidence that evolution takes place Transitional Forms or intermediates show how organisms evolve. The age of fossils can be measured through radiometric dating


Horse evolution :Horse evolution


Whale Evolution :Whale Evolution Tiny hind legs were useless on land and shorter neck and longer tail makes Dorudon similar to modern whales. Walking whale that swims, fish eater the size of a sea lion Whale shaped skull and teeth adapted for hunting fish


Geographic Distribution of Living Species :Geographic Distribution of Living Species Living species are different because of where they are located. They adapted to the environments they are in Ex. Beaver- North America Muskrat- North America Capybara- South America Coypu- South America


Slide 65:Beaver NORTH AMERICA Muskrat Capybara SOUTH AMERICA Coypu Beaver Muskrat Beaver and Muskrat Coypu Capybara Coypu and Capybara


Large Cactus Finch: thick beaks that can feed on large, hard seeds that require strength for crushingSmall Tree Finch: have biting strength at the tips of their beaks which is useful for tearing vegetation :Large Cactus Finch: thick beaks that can feed on large, hard seeds that require strength for crushingSmall Tree Finch: have biting strength at the tips of their beaks which is useful for tearing vegetation


Distribution of Marsupials :Distribution of Marsupials


Anatomy :Anatomy Homologous Structures: structures that have different forms but develop from the same embryonic tissues and have a common ancestor Vertebrate bone structure Vestigial Structures: a structure in an organism that serves no useful function and is reduced in size Ex. Hind limbs of a whale


Slide 69:Human hand Mole foot Bat wing


Homologous Structures :Homologous Structures


Slide 72:Analogous structures are not evidence of a common ancestor. Analogous structures have a similar function.


What would be the vestigial structure on an ostrich? :What would be the vestigial structure on an ostrich? Wings


More examples of vestigial structures :More examples of vestigial structures Fish that live in caves have vestigial non-functioning eyes


Anatomy :Anatomy


Embryology :Embryology Early stage of embryos are very similar Embryonic cells develop in the same order for all vertebrates All vertebrate embryos have three physical features in common Tail Buds that become limbs Pharyngeal gill slits


Slide 78:Example of how embryology shows evidence for evolution identical larvae, different adult body forms similar embryos, diverse organisms


DNA :DNA Organisms can be compared based on DNA DNA sequences are very similar in organisms that share common ancestors


Slide 80:Example from the Dover trial: Genome Sequence Data Tests Human Evolution


Slide 81:Example: the Evolutionary Hypothesis of Common Ancestry Chromosome Numbers in the great apes: human (Homo) 46chimpanzee (Pan) 48gorilla (Gorilla) 48orangutan (Pogo) 48 Testable prediction: If these organisms share a common ancestor, that ancestor had either 48 chromosomes (24 pairs) or 46 (23 pairs).


Slide 82:Chromosome Numbers in the great apes (Hominidae): human (Homo) 46chimpanzee (Pan) 48gorilla (Gorilla) 48orangutan (Pogo) 48 Testable prediction: Common ancestor had 48 chromosomes (24 pairs) and humans carry a fused chromosome; or ancestor had 23 pairs, and apes carry a split chromosome. Centromere Telomere Ancestral Chromosomes


Slide 83:“Chromosome 2 is unique to the human lineage of evolution, having emerged as a result of head-to-head fusion of two acrocentric chromosomes that remained separate in other primates. The precise fusion site has been located in 2q13–2q14.1 (ref. 2; hg 16:114455823 – 114455838), where our analysis confirmed the presence of multiple subtelomeric duplications to chromosomes 1, 5, 8, 9, 10, 12, 19, 21 and 22 (Fig. 3; Supplementary Fig. 3a, region A). During the formation of human chromosome 2, one of the two centromeres became inactivated (2q21, which corresponds to the centromere from chimp chromosome 13) and the centromeric structure quickly deterioriated (42).” Homo sapiens Inactivated centromere Telomere sequences Hillier et al (2005) “Generation and Annotation of the DNA sequences of human chromosomes 2 and 4,” Nature 434: 724 – 731. Human Chromosome #2 shows the exact point at which this fusion took place


Slide 84:includes Evidence of Evolution which is composed of which indicates which implies which implies


Beginning Questions :Beginning Questions Identify characteristics of birds that provide information about their diets. Beak size and shape Size of Bird


Beginning Questions :Beginning Questions Insects are the largest group of animals on the Earth. Why do you think so many species of insects have evolved? Insects are adapted to many different kinds of environments and rely on many different food sources.


Beginning Questions :Beginning Questions Make a chart to compare how these two bears live and survive in their environments (include the habitats of the bears, what kind of food they eat, how their camouflage helps them survive in their habitat, and why each might not survive in the other’s environment.)


Chart :Chart


Natural Selection at Work :Natural Selection at Work The environment controls the direction and amount of change of an organism Ex. Polar bear- white fur allows it to blend in, warmer climate would not have this protection.


Example of Natural Selection :Example of Natural Selection What is tuberculosis? (what causes it, what are the symptoms) Lung disease Caused by bacteria (Mycobacterium tuberculosis) Kills more people than any other infectious disease. Symptoms: coughing, sharp chest pain when breathing, spitting up blood, flu symptoms(fever, tired, etc).


Example of Natural Selection :Example of Natural Selection Why is TB so deadly? TB mutates very easily When it mutates it creates TB strains that are resistant to antibotics


Evolution of Antibiotic Resistance :Evolution of Antibiotic Resistance Explain how bacteria become resistant to antibiotics. (Use the example of TB) Mutated bacteria develop which are resistant to antibiotics Normal bacteria die, mutated live Mutated reproduce and infect host


Ex. Gonorrhea :Ex. Gonorrhea In the 1960s penicillin and ampicillin were able to control most cases of gonorrhea. Today, more than 24 percent of gonorrheal bacteria in the U.S. are resistant to at least one antibiotic, and 98 percent of gonorrheal bacteria in Southeast Asia are resistant to penicillin.


How to control antibiotic resistance :How to control antibiotic resistance Don’t use antibiotics to treat viral infections Avoid mild doses of antibiotics over long time periods. When treating a bacterial infection with antibiotics, take all your pills. Use a combination of drugs to treat a bacterial infection. Reduce or eliminate the “preventive” use of antibiotics on livestock and crops.


Evolution of Darwin’s Finches :Evolution of Darwin’s Finches List the different types of finches Darwin found and what type of food they eat. Ground Finches Large Bills: seeds Narrower bills: insects, fruits Sharp beak: drink the blood of sea birds


Evolution in Darwin’s Finches :Evolution in Darwin’s Finches Explain the number and types of finches that were found in the dry years compared to the wet years.


Evolution of Darwin’s Finches :Evolution of Darwin’s Finches What do you think: Why do you think beak size returns to normal following each dry year? There are more seeds available and beak size is not as important


Evolution of Darwin’s Finches :Evolution of Darwin’s Finches What do you think: What would have to happen for beak size to remain large in the population over many years? There would have to be many dry years where only large seeds are found.


Formation of New Species :Formation of New Species Divergence: accumulation of differences between groups Speciation: formation of a new species


Hypothetical Example :Hypothetical Example The scene: a population of wild fruit flies minding its own business on several bunches of rotting bananas, cheerfully laying their eggs in the mushy fruit...


Slide 101:Disaster strikes: A hurricane washes the bananas and the immature fruit flies they contain out to sea. The banana bunch eventually washes up on an island off the coast of the mainland. The fruit flies mature and emerge from their slimy nursery onto the lonely island. The two portions of the population, mainland and island, are now too far apart for gene flow to unite them. At this point, speciation has not occurred—any fruit flies that got back to the mainland could mate and produce healthy offspring with the mainland flies.


Slide 102:The populations diverge: Ecological conditions are slightly different on the island, and the island population evolves under different selective pressures and experiences different random events than the mainland population does. Morphology, food preferences, and courtship displays change over the course of many generations of natural selection


Slide 103:So we meet again: When another storm reintroduces the island flies to the mainland, they will not readily mate with the mainland flies since they’ve evolved different courtship behaviors. The few that do mate with the mainland flies, produce unviable eggs because of other genetic differences between the two populations. The lineage has split now that genes cannot flow between the populations.


Forming Subspecies :Forming Subspecies Natural Selection results in the evolution of offspring that are better adapted to their environment


Forming Subspecies :Forming Subspecies Subspecies: populations of the same species that differ genetically because they adapted to different environments


What barriers may isolate two related groups? :What barriers may isolate two related groups? Geographically isolated (on different continents) Reproduce at different times Physical barriers (mountains, canyons)


Evolution is a working science :Evolution is a working science New discoveries are being made every year to add to the puzzle


Let it all Come Together! :Let it all Come Together! Put these steps (natural selection, variation, new species, divergence, isolation) of making a new species in order in which they occur. Beside each word write a small description of the word.


Slide 109:Evolution Divergence Genetic Variation Extinction Natural Selection Speciation Environment Is driven by Does not occur if species cannot adapt Which results in Populations Occurs in Which requires Conditions in the Which lead to Can result in