What is Evolution??

Objectives: 1) 1) Define evolution 2) 2) Compare the ideas of Lamarck and Darwin

EVOLUTION The biological process by which living things change over time

Jean Baptiste de Lamarck ( ) 1 st to propose that organisms undergo change over time as a result of natural phenomena (1809) 1 st to propose that organisms undergo change over time as a result of natural phenomena (1809) Use and disuse Use and disuse

Theory of acquired characteristics Theory of acquired characteristics organisms acquired traits during their lifetime organisms acquired traits during their lifetime these traits could be passed on these traits could be passed on Tendency toward perfection Tendency toward perfection LAMARCK WAS WRONG IN MECHANISM LAMARCK WAS WRONG IN MECHANISM

Charles Darwin: The Father of Evolution Darwin was NOT the first person to propose evolution… Darwin was NOT the first person to propose evolution… He did propose a mechanisms for evolution called Natural Selection He did propose a mechanisms for evolution called Natural Selection Darwin’s ideas began during his voyage on the HMS Beagle ( ) Darwin’s ideas began during his voyage on the HMS Beagle ( )

Voyage of the Beagle Darwin was the ship’s naturalist As the Beagle went around the world, Darwin collected and studied the various life forms

Especially influenced by his findings at the Galapagos Islands off the coast of S. America Island species similar to ones on the mainland but uniquely suited to their own environment Galapagos species were more similar to mainland species than to those in similar environments in other parts of the world Why??

Green Iguana – S. America Land Iguana - Galapagos Marine Iguana - Galapagos

Upon his return to England, Darwin spent over 20 years analyzing his findings and working on his theory of HOW evolution occurs Proposed Natural Selection as the mechanism for evolution Received a letter from Alfred Wallace who had independently arrived at same conclusions 1858 – Darwin & Wallace release their findings 1859 – Darwin publishes “On The Origin of Species”

What is a “theory”? It is NOT a careless suggestion or reason why things may have happened It is NOT a careless suggestion or reason why things may have happened It IS a well-supported, testable explanation of phenomena that occur in the natural world It IS a well-supported, testable explanation of phenomena that occur in the natural world What began as hypothesis of how life has changed over time is now supported by a huge body of EVIDENCE What began as hypothesis of how life has changed over time is now supported by a huge body of EVIDENCE