Transcript Slide 1
Let’s do a little experiment What is Natural Selection? • It is a simple concept, with many complexities surrounding it. • Favorable heritable traits become more common, and unfavorable heritable traits become less common. • Those that have favorable traits survive and reproduce • Our environment and our genes make us who we are---environmental pressures force our species to adapt • If we adapt, our genes are passed on Which one would you choose? Here are some examples of highly adapted creatures Antibiotics—the perfect example of natural selection Bacteria reproduce quickly—more mutations—more change—more likely to adapt Guided Practice • I want you all to each write down an advantageous trait of an organism, and tell me why the species had to adapt to obtain that trait • Can anyone think of a disadvantageous trait in an organism that is still around? These Changes occur very very SLOWLY Our earth has been around for 4.6 billion years and has had abundant life for over 500 million years, so a great deal can and has happened. • • • • • • • • • • • • • • http://www.reneliomarin.com/images/img_large/canvas/FirstStepEvolu.jpg http://dezignus.com/wp-content/uploads/2007/10/psevolution.jpg http://www.listadodeanimales.com/animales/images/hojainsecto.jpg http://www.gly.uga.edu/railsback/1122/1122Dogs.jpeg http://images.google.com/imgres?imgurl=http://tugagames.com/victor/wpcontent/uploads/2007/10/crescentmoth.jpg&imgrefurl=http://www.drollthings.com/%3Fp%3D682&h=332&w=450&sz=49&hl=en&star t=6&um=1&tbnid=ygRYo626M60NsM:&tbnh=94&tbnw=127&prev=/images%3Fq%3Dcamouflage %2Bmoth%26um%3D1%26hl%3Den%26client%3Dfirefoxa%26channel%3Ds%26rls%3Dorg.mozilla:en-US:official%26sa%3DG http://www.treesforlife.org.uk/images/poplar_hawkmoth_caterpillar.jpg http://www.learner.org/channel/courses/essential/life/images/show5.maize_teosinte.jpg http://homepage.mac.com/wildlifeweb/mammal/african_wild_dog/african-wild-dog_02tk.jpg http://animals.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/animals/images/primary/ dingo.jpg http://www.bioteams.com/images/what_teams_can.jpg http://www.africanfauna.com/images/jackal.jpg http://k-punk.abstractdynamics.org/archives/orchid-thumb.jpg http://farm1.static.flickr.com/55/117768119_b1b76f67d3.jpg http://lifeboat.com/images/bacteria.jpg