History of Evolutionary Thought Lec 3, Slides of Theory of Evolution

Download History of Evolutionary Thought Lec 3 and more Slides Theory of Evolution in PDF only on Docsity! History of Evolutionary Thought Announcements: 1. iClickers will be used today for points (Contact iClicker tech support for help) 2. 1st Quiz is open (due this Fri @4:59pm) Evolution of Evolutionary Thought 2Newton’s Corner Sculpture, Colorado State University “If I have seen further than certain other men, it is by standing upon the shoulders of giants.” - Sir Isaac Newton on his dependency upon Galileo’s and Kepler’s works in physics and astronomy Evolution did not start with Darwin 5 Ancient Greece Medieval Islam Ancient Rome Ancient China Carl Linnaeus (1707-1778) 6 §Father of modern systematics (classifying organisms) § Invented taxonomy (naming organisms) §Nested Hierarchy Grizzly bears are nested in Family Ursidae, nested in the Order Carnivora, nested in the Class Mammalia, etc.) >precursor to common decent George-Louis Leclerc, Comte de Buffon (1707-1788) 7 § Father of Biogeography § Buffon’s Law: despite similar environments, different regions have unique species § Species variation exists (got the mechanism wrong) • New environment = New particles • New particles = New species Mammoths lived in taiga Turned into Elephants Migrated to new habitat where things live{why Charles Lyell (1797-1875) 10 § Principles of Geology (1830) § Contemporary of Darwin § Changes in rock layers only appear sudden when viewed on a timescale that is too short Uniformitarianism: geologic processes shaped Earth gradually & constantly over a long timescale, not through catastrophism☐ Charles Darwin (1809-1882) 12 §Went to medical school o Tried it…didn’t like it ! § Went to seminary school o Meh… o Professors saw talent – recommended for voyage around the world H.M.S Beagle • 5 year mission to seek out new life • Ship’s Naturalist The Voyage of the H.M.S. Beagle 1831 - 1836 Britain” EUROPE CS KS S ATLANTIC ” *p,,, OCEAN ; AFRICA SS paciric “2 OCEAN SOUTH Equator Mala’ y PD AMERICA Archipelago 6 . Chite>& Brazil () USTRALI PACIFIC [| % S a hania aL Galapagos Islands, Ecuador • Largest impact on his evolutionary thinking • Struck by the organisms being so similar to mainland, yet still differences between islands. Chaco tortoise (mainland) (Chelonoidis chilensis) Galapagos tortoise (Chelonoidis nigra) Darwin’s Journey & Synthesizing Prior Knowledge 16 But ? What is the of evolution? Galápagos mockingbirds 17Fig. 3.9 M. trifasciatus M. macdonaldi Mimus parvulus M. melanotis The Voyage of the H.M.S. Beagle From the Galapagos to New Zealand & Ausiralia SMES SS. r B23} —£ eo Great Y Archipelago \ \ Tasmania New Zealand The gradual evolution of a theory… 21 § Spent next 20 years working on, testing, sharing, and revising his ideas. §Gathered more, and more, and more support prior to publishing “I determined to collect blindly every sort of fact which could bear any way on what are species…. I am almost convinced (quite contrary to opinion I started with) that species are not (it is like confessing a murder) immutable.” - Letter by Darwin (1844) Domestication of Pigeons Using Artificial Selection to understand Natural Selection 22 • Pigeon breeding popular in 19th C Britain • Interesting varieties FAVORED by breeders • Trace how: §new traits arise randomly §ancestor variety gives rise to descendent varieties § look very different wq.HR#. Independently derived Evolution by Natural Selection Alfred Russell Wallace (1823-1913) 23 “I never saw a more striking coincidence…. So all my originality, whatever it may amount to, will be smashed” - Letter from Darwin to Charles Lyell (1858) Ali Wallace Wallace’s Assistant Malaysia 5 main points of Darwin’s theory On the Origin of Species by Natural Selection 27 4. Populations evolve (not individuals) • Changes in the proportion of variant individuals • Not Lamarckian changes 5. Mechanism = Natural Selection • Competition among individuals causes proportions in population to change • Leads to adaptations Ernst Mayr (1982) - mecn. Darwin prepared, but there are other mean. Ever since Darwin… 30 Lamarck Lyell Linnaeus Wallace Darwin YOU • Scientists continued (and continue!) to test new hypotheses • Discover other mechanisms for evolution (not just Natural Selection) Evolution of Evolution: 150 Years of Darwin’s On the Origin of Species https://www.nsf.gov/news/special_reports/darwin/ Explore evolutionary theory and give YOU the tools to “see further”!