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 total variety of all the organisms in the biosphere = ________________ Where did all these different organisms come from? How are they related? BIODIVERSITY http://www.millan.net

What scientific explanation can account for the diversity of life? ANSWER: A collection of ______________, __________, and ___________ known as ________________________ Scientific facts observations hypotheses EVOLUTIONARY THEORY

Charles Darwin H.M.S. Beagle 5 year The person who contributed the http://harrier.users.netlink.co.uk/Darwin_sm.jpg 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 5 year Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

Who Was Charles Darwin? Galápagos Islands finches tortoises 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 ________. H.M.S. Beagle Galápagos Islands finches tortoises http://www.darwinadventure.com/pictures/galapagos_giantortoise.jpg http://mikebaird.com/ecuador/images/galapagos_off_ecuador_ng_map.jpg

Some were hot and dry, with little vegetation. 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. climates Biology by Miller and Levine; Prentice Hall Publishing©2006 unique assortment

Giant Tortoises of the Galápagos Islands Section 15-1 and on Pinta Island, tortoise necks were somewhere in between Pinta Tower Pinta Island Intermediate shell Marchena James Fernandina Santa Cruz Isabela Santa Fe Hood Island Saddle-backed shell Floreana Hood On the desert-like Hood Island, tortoises had long necks… Isabela Island Dome-shaped shell …while on the lush rainforest of Isabela Island, tortoises had short necks…

same species different isolated 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. Biology by Miller and Levine; Prentice Hall Publishing©2006 same species different isolated

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 ______________ by _________________ occurring over __________ periods of time, and is _______________ old. James Hutton Earth was shaped geological forces very long millions of years http://www.creationism.org/books/TaylorInMindsMen/TaylorIMMc03.htm

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 http://www.biologydaily.com/biology/Sir_Charles_Lyell

Ideas that shaped Darwin’s thinking: Theory of Pangaea …and continental drift http://wrgis.wr.usgs.gov/docs/usgsnps/animate/A08.gif

insufficient space & food http://www.nndb.com/people/250/000024178/malthus.jpg Ideas that shaped Darwin’s thinking: _____________________ He 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

Jean-Baptiste Lamarck (1809) http://www.educa.rcanaria.es/fundoro/00.corsi.htm 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. Jean-Baptiste Lamarck (1809) changed over time descended Inheritance of Acquired traits

The male fiddler crab uses its front claw to attract mates and ward off predators. Through repeated use, the front claw becomes larger. The fiddler passes on this acquired characteristic to its offspring

What’s wrong with Lamarck’s hypothesis? http://www.geocities.com/arnold_schwarzenegger_pictures/ 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! Acquired traits may help an organism, but they won’t be passed on to offspring.

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 http://pegasus.cc.ucf.edu/~he599900/giraffeeating.jpg