Darwin’s Theory of Evolution The Puzzle of Life’s Diversity Chapter 15-1 Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

The person who contributed the most to our understanding of evolution was ______________________ In 1831, at age 22, he joined the crew of the _______________ as a naturalist for a ________ voyage around the world. Charles Darwin H.M.S. Beagle Image from: Biology by Miller and Levine; Prentice Hall Publishing© year

During his travels, Darwin wrote thousands of pages in his journals, drew pictures of the things he saw, and collected a vast amount of ______________ that led him to propose a _______________________ about the way _____________. revolutionary hypothesis evidence life changes

DARWIN WONDERED? Why do Argentina and Australia have ________ ______ even though they have ________ grassland ____________? Why are there no ______ in Australia and no ________ in England? Why have so many species disappeared? How are these ______ species related to living species? different animals similar ecosystems rabbits kangaroos extinct

Who Was Charles Darwin? While on his voyage around the world aboard the ____________, Charles Darwin spent about one month observing life on the ________________. There, he encountered some unique animals, such as ______ and ________. Galápagos Islands H.M.S. Beagle finchestortoises

The Galάpagos Islands are close together but have very different _______. Some were hot and dry, with little vegetation. Others had more rainfall and were rich in vegetation Each island had its own _____ _________ of plant and animal species. Biology by Miller and Levine; Prentice Hall Publishing©2006 climates assortment unique

Go to Section: Pinta Island Intermediate 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 Section 15-1 On the desert-like Hood Island, tortoises had long necks… …while on the lush rainforest of Isabela Island, tortoises had short necks… and on Pinta Island, tortoise necks were somewhere in between

After his voyage, Darwin spent a great deal of time thinking about his findings. He began to wonder if animals living on different islands had once been members of the ____________ that had developed _________ characteristics after becoming _______ from one another in different habitats. same species different isolated Biology by Miller and Levine; Prentice Hall Publishing©2006

Darwin’s Theory of Evolution Ideas that Shaped Darwin’s Thinking Chapter 15-2 Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

Ideas that shaped Darwin’s thinking: In 1785 ______________ proposes that the EARTH was _______ by _________________ occurring over __________ periods of time, and is _______________ old. very long James Hutton shaped geological forces millions of years

Ideas that shaped Darwin’s thinking: In 1833 ___________ explains that the geological processes still ___________ have shaped Earth’s features over ________________ Charles Lyell occurring now long periods of time

Ideas that shaped Darwin’s thinking: Theory of Pangaea …and continental drift

Ideas that shaped Darwin’s thinking: observed that babies were being born faster than people were dying. He reasoned that if the human population continued to grow, sooner or later there would be _______________________ Thomas Malthus (1798) insufficient space & food

Ideas that shaped Darwin’s thinking: ___________________________ was one of first scientists to recognize living things _______________ and that all species were ________ from other species. Lamarck published his hypothesis of ________________________ the year Darwin was born. changed over time Jean-Baptiste Lamarck (1809) descended Inheritance of Acquired traits

The male fiddler crab uses its front claw to _________mates and fight off _____________. Through _________ use, the front claw becomes ________. The fiddler passes on this __________ characteristic to its offspring attract predators larger repeated acquired

What’s wrong with Lamarck’s hypothesis? Lamarck didn’t know about genes and how traits are _______. If you lifted weights your whole young adult life, and then you had children, would your kids be more muscular? inherited NO! ________ traits can ____ be __________ to their offspring. ACQUIRED NOT PASSED ON

What’s right with Lamarck’s hypothesis? Lamarck was first to develop a scientific hypothesis about _______ and recognize that organisms are ________________________ evolution adapted to their environments

a.The earth is really old, and slowly changes b.Living things pass changes on to their offspring, leading to species changes c.Sooner or later growing populations run out of resources d.Living things change slowly over time because of competition for resources, and pass those changes on to their offspring Hutton Lyell Malthus Lamarck Match the letter of the idea with the man or men who proposed it:

a.The earth is really old, and slowly changes b.Living things pass changes on to their offspring, leading to species changes c.Sooner or later growing populations run out of resources d.Living things change slowly over time because of competition for resources, and pass those changes on to their offspring Hutton Lyell Malthus Lamarck a. c. b. d.