DESCENT WITH MODIFICATION A Darwinian View of Life AP BIOLOGY Chapter 22 Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

WHO INFLUENCED DARWIN’S THINKING Figure 22.2 Linnaeus (classification) Hutton (gradual geologic change) Lamarck (species can change) Malthus (population limits) Cuvier (fossils, extinction) Lyell (modern geology) Darwin (evolution, nutural selection) Mendel (inheritance) Wallace (evolution, natural selection) 1750 American Revolution French Revolution U.S. Civil War 1800 1850 1900 1795 Hutton proposes his theory of gradualism. 1798 Malthus publishes “Essay on the Principle of Population.” 1809 Lamarck publishes his theory of evolution. 1830 Lyell publishes Principles of Geology. 1831–1836 Darwin travels around the world on HMS Beagle. Darwin begins his notebooks on the origin of species. 1837 Darwin writes his essay on the origin of species. 1844 Wallace sends his theory to Darwin. 1858 The Origin of Species is published. 1859 Mendel publishes inheritance papers. 1865 Image from: AP BIOLOGY by Campbell and Reece

Species are fixed (unchanging) BUT recognized similarities Image from: http://www.ucmp.berkeley.edu/history/aristotle.html Aristotle- (384-322 B.C.) Species are fixed (unchanging) BUT recognized similarities Arranged life forms on a scale of increasing complexity scala natura- “scale of nature” http://www.kheper.net/topics/greatchainofbeing/index.html

Binomial Nomenclature: Naming system that gives organisms a Image from: http://www.medusozoa.com/images/linnaeus.jpg Founder of TAXONOMY-1735 Science of grouping & naming Sought to discover order in the diversity of life “for the greater glory of God” Each creature was special- NO evolutionary link Devised classification system based on morphology (form and structure) (1707-1778) Binomial Nomenclature: Naming system that gives organisms a two part scientific name- Genus species Still used today

LINNAEUS’S SYSTEM Nested hierarchy Taxon = classification unit to which organisms are assigned Ex: Panthera is a taxon at the genus level Mammalia is a taxon at the class level http://content.answers.com/main/content/wp/en-commons/thumb/d/d6/150px-Biological_classification_L_Pengo.svg.png

Kidspiration by Riedell Image Sources: see end of show

Kingdom Phylum Class Order Family Genus Species Animalia Chordata Kids Prefer Cheese Over Fried Green Spinach Kings Play Chess On Fat Green Stools King Phillip Cried Oh For Goodness Sake! Kingdom Phylum Class Order Family Genus Species Animalia Chordata Mammalia Carnivora Felidae Panthera leo http://www.vetmed.wisc.edu/dms/fapm/personnel/tom_b/2004-lion.jpg

GENUS = group of closely related species (Includes many kinds of bears) SPECIES = unique to each kind of bear GENUS = Ursus Ursus arctos Ursus maritimus Ursus americanis http://www.macecanada.com/images/bears/kodiak_bear.gif http://students.cs.byu.edu/~tole/Virtual%20Zoo/polar-bear.jpg http://en.wikipedia.org/wiki/Image:Black_bear_large.jpg

Homo sapiens Homo sapiens Genus and species assignments provide 2 part scientific name Homo sapiens Homo sapiens Image from: http://www.earlylearning.ubc.ca/images/photo_baby.jpg

Modern Taxonomy has added more Kingdoms AND more levels (DOMAINS) Linneaus only used 2 kingdoms (Plants & Animals) Domains are larger than Kingdoms and are based on the differences in ribosomal RNA

Ideas that shaped Darwin’s thinking: George Cuvier – Father of Paleontology http://upload.wikimedia.org/wikipedia/commons/2/28/Georges_Cuvier.jpg ANTI-EVOLUTONIST Fossils are remains of extinct life forms “CATASTROPHISM” - boundaries represent floods, droughts, etc. that destroyed many species living at that time

Ideas that shaped Darwin’s thinking: 1795 –James Hutton “GRADUALISM” Profound changes can result from cumulative effect of slow but continuous processes Proposed that the Earth was shaped by geological forces occurring over very long periods of time, and is MILLIONS not THOUSANDS of years old. http://www.creationism.org/books/TaylorInMindsMen/TaylorIMMc03.htm

Ideas that shaped Darwin’s thinking: 1833-Charles Lyell Incorporated Hutton’s ideas into “UNIFORMITARIANISM” Geological processes that shaped Earth are still operating at same rate. Darwin read his book on the Beagle voyage http://www.biologydaily.com/biology/Sir_Charles_Lyell

MODERN GEOLOGY http://wrgis.wr.usgs.gov/docs/usgsnps/animate/A08.gif

Ideas that shaped Darwin’s thinking: Thomas Malthus (1798) http://www.nndb.com/people/250/000024178/malthus.jpg Ideas that shaped Darwin’s thinking: Thomas Malthus (1798) wrote essay on population growth Human suffering (disease, famine, homelessness, and war) are consequences to human population increasing faster than food and other resources

Ideas that shaped Darwin’s thinking: Jean Baptiste Lamarck (1744-1829) http://www.educa.rcanaria.es/fundoro/00.corsi.htm Ideas that shaped Darwin’s thinking: Jean Baptiste Lamarck (1744-1829) One of first scientists to recognize that living things changed over time and that all species were descended from other species. 1809- Published his ideas about “Inheritance of Acquired Characteristics” the year Darwin was born

INHERITANCE OF ACQUIRED CHARACTERISTICS The male fiddler crab uses its front claw to attract mates and ward off predators. “USE or DISUSE” = Use it or lose it 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/ Lamarck didn’t know about genes and how traits are inherited. Acquired traits are not passed on to offspring Or are they? . . . New field of EPIGENETICS is exploring this

What’s right with Lamarck’s hypothesis? Lamarck was first to develop a scientific hypothesis about evolution and recognize that organisms are adapted to their environment http://pegasus.cc.ucf.edu/~he599900/giraffeeating.jpg

Slide by Kim Foglia@ http://www.explorebiology.com/

Who Was Charles Darwin? In 1831, 22-year old Charles Darwin left England as naturalist aboard the HMS Beagle for 5 year voyage around the world. Mission: Chart the South American coastline Darwin noticed plants and animals were different from those he knew in Europe Wrote thousands of pages of observations and collected vast number of specimens http://www.solarnavigator.net/history/explorers_history/HMS_Beagle.jpg

Who Was Charles Darwin? Darwin spent a month observing life on the Galapagos Islands Each island has different rainfall and vegetation and its own unique assortment of plant and animal species. Biology by Miller and Levine; Prentice Hall Publishing©2006 http://mikebaird.com/ecuador/images/galapagos_off_ecuador_ng_map.jpg

Who Was Charles Darwin? Although animals on Galapagos resemble species on the South American mainland, many species were found no where else in the world = ENDEMIC http://www.darwinadventure.com/pictures/galapagos_giantortoise.jpg http://www.destination360.com/south-america/ecuador/galapagos-animals.php http://www.photoseek.com/galapago.html

DARWIN’S FINCHES Darwin collected 14 species of finches and hypothesized that the Galapagos had be colonized by organisms from the mainland that had then diversified on the various

Who Was Charles Darwin? After Darwin returned to England in 1836, he spent years examining specimens he brought back from voyage and filling notebooks with his ideas. He did not rush to publish his ideas because they disagreed with the fundamental scientific views of his day. In 1844 he wrote an essay describing his ideas and asked his wife to publish it if he died. http://www.elsie.brandeis.edu/images/journals.gif

In 1858 Alfred Russel Wallace, another Naturalist working in the West Indies, wrote an essay describing his work that summarized the same ideas Darwin had been thinking about for 25 years! http://www.thesecondevolution.com/wallace&darwin.jpg

Suddenly Darwin had incentive to publish the results of his work! On the Origin of Species by Means of Natural Selection presented evidence and proposed a mechanism for evolution that he called NATURAL SELECTION http://www.loc.gov/exhibits/world/images/s125.jpg