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Evidence of Evolution. Fossils Provide Evidence. Animal fossils show a pattern of development from early ancestors to their modern descendants. There are gaps in the fossil record. Fossils are rare.
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Fossils Provide Evidence • Animal fossils show a pattern of development from early ancestors to their modern descendants. • There are gaps in the fossil record. • Fossils are rare http://www.google.com/imgres?imgurl=http://www.wallsofthewild.com/pterodactyl.jpg&imgrefurl=http://www.wallsofthewild.com/pter.htm&usg=__9caIuOdNvnUNeTtJd_BwijJIK5M=&h=479&w=800&sz=100&hl=en&start=0&zoom=1&tbnid=vSsuBQ-o-EFlxM:&tbnh=131&tbnw=219&ei=-6ahTYjRF6iU0QGo5JSEBQ&prev=/images%3Fq%3Dpterodactyl%26um%3D1%26hl%3Den%26rlz%3D1G1GGLQ_ENUS398%26biw%3D1438%26bih%3D680%26tbm%3Disch&um=1&itbs=1&iact=hc&vpx=1109&vpy=148&dur=1895&hovh=174&hovw=290&tx=91&ty=85&oei=-6ahTYjRF6iU0QGo5JSEBQ&page=1&ndsp=19&ved=1t:429,r:5,s:0
FOSSIL: • The preserved or mineralized remains (bone, petrified tree, tooth, or shell) or imprint of an organism that lived long ago. http://www.maropeng.co.za/images/uploads/fossil_lg.jpg
Three Major Points • Earth is about 4.5 billion years old • Organisms have inhabited the earth for most of its history • All organisms living today evolved from earlier, simpler life-forms.
Crinoid fossil • Found in an 800 MILLION year old rock from Indiana • http://www.youtube.com/watch?v=cZcomBnNKXg
Paleontologist • Scientist who studies fossils. • http://blogs.answersingenesis.org/museum/pictures/Dino-dig-8-30-06-0151.jpg
Paleontology • Paleontologists can determine how old fossils are. • They use radiometric dating to determine the half life. • http://www.furryelephant.com/content/radioactivity/half-life-simulation/
Evolution of Whales http://biologos.org/uploads/static-content/Figure_1.png
Biological Molecules Provide Evidence • Proteins • Amino acids are the building blocks of proteins • Amino acid + amino acid + amino acid = PROTEIN • The more amino acids two species have in common, the more closely related they are.
Biological Molecules Provide Evidence • Nucleic Acids • Scientists can determine the number of nucleotide differences among organisms to see how closely related they are. • They make DNA comparisons.
Anatomy & Development Suggest Common Ancestry • Vestigial Structures • Homologous Structures • Development of Embryos
Vestigial structures: • Structures that are present in an organism but are reduced in size and are no longer useful. • Examples: Wings of flightless birds, fingernails on manatee fins, and goosebumps (not a structure but a reaction).
Homologous structures • Structures that similar in form but different in function. • Examples: Forelimbs of vertebrates
Guess the Embryo http://www.pbs.org/wgbh/nova/evolution/guess-embryo.html