Diversity and Evolution SC.912.L.151 SC.912.L.15.10 SC.912.N.1.3 SC.912.N.2.1 SC.912.L.15.8

Darwin’s Theory of Evolution by Natural Selection

Ideas that shaped Darwin Before Darwin, people believed Earth was 6,000 years old and also relatively unchanged 1. Comte de Buffon Studied the fossil record showed that the Earth might be much older (4.3 and 4.5 billion years old) 2. James Hutton Layers of rock are moved by forces beneath Earth’s surface Most geological processes operate extremely slowly. 3. Charles Lyell geologic process that shaped the Earth in the past still continue today

Ideas that shaped Darwin Before Darwin people believed that species were fixed….meaning plants and animals had always been the way they are today 4. George Cuvier based fossils from different rock layers gave evidence that organisms from the past differed greatly from living species

5. Thomas Malthus suggested that if the human population continued to grow unchecked, eventually there wouldn’t be enough food and living space for everyone Famine, disease, and war

Ideas that shaped Darwin 6. Jean Baptiste de Lamarck’s * 1809 published his theory of evolution * “More complex organisms evolved from prior, less complex organisms”

Larmarck Use and Disuse Body parts develop with increased usage Unused body parts weaken CORRECT Inheritance of Acquired characteristics Body parts acquired during lifetime of organism can be passed on to offspring INCORRECT (only changes to genetic material in gametes can be passed down) Natural transformation of species Organisms produced offspring with changes, transforming each subsequent generation into a slightly different form, toward a higher order of complexity Species never became extinct Species never split off into two new species INCORRECT

Evolution Assessment Pick up a piece of white paper from up front. You are creating a POSTCARD that Charles Darwin is writing to Jean Baptiste Lamarck about what his observed on his expedition to the Galapagos island. FRONT OF PAPER- TYPE Two WELL SUPPORTED paragraphs CREATIVELY describing what Darwin has witnessed in the Galapagos Islands and his theories and ideas. Include and UNDERLINE vocabulary words and make sure to make your explanation understandable to anyone FIRST PERSON (as Charles Darwin) to your friend Lamarck Address Lamrack’s views on evolution and explain how your evidence does not support his findings BACK OF PAPER- Using your colored pencils, create a PICTURE(s) of what Darwin observed on his expedition…remember, sometime postcards have a few different pictures with one phrase on the front…be CREATIVE Your picture should support your paragraph on the back

100 point assessment AND project Category Maximum Points Neatness 10 Creativity (overall postcard. Language, presentation, etc) 20 Followed Directions Relevant illustrations Grammar, spelling, structure (complete sentences) Two paragraphs (5-7 sentences each) Includes ALL Ideas of Darwin’s theory 8 Includes ALL Ideas of Lamarck’s theory 6 Colored

Voyage of the Beagle Darwin made a voyage around the word collecting thousands of plant and animal specimens. His observations and collected evidence led him to propose hypothesis that living things change over time Theory of Evolution through natural selection.

Voyage of the Beagle Darwin noticed that plants and animals on the Galapagos islands of the coast of Ecuador were different from those on the mainland and also from island to island

Neck-size vs. Vegetation height

Galapagos’ Finches

Galapagos’ Finches

Darwin’s Theory Natural Selection 1859 “On the Origin of Species” “In this book he presented all the evidence he had gathered over the past several years…” Both from his own observations and from the influential work of others. proposed a mechanism for evolution called… Natural Selection

Natural Selection The ability of an organism to survive and reproduce in its specific environment is called fitness. Individuals with characteristics that are not well suited to their environment either die or leave few offspring Individuals that are better suited to their environment survive and reproduce most successfully. Darwin called this process Survival of the Fittest, or Natural Selection. Use the silly duck example to emphasize the idea of fitness as having advantageous characteristics. Ask the students to identify the duckling which is most fit for its environment (in the context of the picture).

FITNESS describes how good a particular genotype is at leaving offspring in the next generation relative to how good other genotypes are at it Depends on ENVIRONMENT organism lives in A genotype's fitness includes: ability to survive Ability find a mate Ability to produce offspring — and ultimately leave its genes in the next generation. if brown beetles consistently leave more offspring than green beetles because of their color, brown beetles had a higher fitness.

Fitness Caring for your offspring and producing thousands of young (many of whom won't survive) and sporting fancy feathers that attract females are a burden to the health and survival of the parent Strategies DO increase fitness help the parents get more of their offspring into the next generation

Adaptations Superior inherited traits to help an organism survive better in its environment Adaptations increase an individuals fitness

4 Principles of Natural Selection Variation Competition Excess offspring Survival of the Fittest Click here for more Details!

4 Main Principles of Natural Selection Variation exists within a population Organisms compete for limited resources Organisms produce more offspring than can actually survive Individuals with variations suitable for their habitat are the ones that SURVIVE and REPRODUCE

Three species of lizard. B- The ones at the bottom live in the shrubland, and are colored to blend in. The top pictures show the same species of lizard, but the variety that lives in the White Sands They all evolved to become white (camouflage) The DNA on the bottom shows the location of the mutation that gives the white color

1. Inherited Variation Individual organisms within the population differ. Most of this variation is determined by genetic inheritance (recombination), but sometimes it is the result of genetic mutations. SC.912.L.15.15 Describe how mutation and genetic recombination increase genetic variation.

2. Struggle for Existence Because so many offspring are produced, many will die due to a lack of resources, predation, disease, or other unfavorable conditions. Have students analyze the pictures. Ask them to explain the struggle for existence that is evident in each. 1) The slowest or weakest wildebeests will succumb to predation before fast or strong ones. 2) Competition for limited (food) resources leaves some members of the group, probably the smallest or least agile, hungry.

3. Overproduction of Offspring Organisms produce more offspring than can survive. Many of the offspring do not survive to reproductive age.

4. Differential Reproduction Individuals best suited to their environment survive and reproduce most successfully. Therefore these organisms pass their advantageous traits to their offspring while offspring with disadvantageous traits die or produce fewer offspring.

Descent with Modification Natural selection causes species to change over time. Species alive today descended with modification from ancestral species.