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Paleontology Study of prehistoric life. Fossils preserved remains or traces of organisms; evidence of past life. http://evolution.berkeley.edu/evolibrary/article/0_0_0/lines_03. Paleontology. The Fossil Record Fossils and their placement in rock formations and sedimentary strata.
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PaleontologyStudy of prehistoric life Fossils • preserved remains or traces of organisms; • evidence of past life http://evolution.berkeley.edu/evolibrary/article/0_0_0/lines_03
Paleontology The Fossil RecordFossils and their placement in rock formations and sedimentary strata http://www.nap.edu/openbook.php?record_id=6024&page=12
Paleontology How fossils are formed http://www.wwnorton.com/college/anthro/our-origins2/img/AskClarkFAQs/Figure-8.4.jpg
Paleontology • Radiochemistry • Age of the sample is calculated based on the amount of radioactive elements contained • C14 N14 upon an animal’s death • C14>C12 = older organisms • K40 for older samples • Geology • Estimate of fossil’s age in comparison with other fossils • Layers may not have been deposited horizontally or may have been overturned http://evolution.berkeley.edu/evosite/lines/IIIAchronology.shtml
Paleontology Fossils link the present with the past • Baleonopteramusculus(blue whale) • Modern marine mammal • Basilosaurus • “king lizard” • w/ 0.5m hind legs, w/ some bones similar to those of land mammals • Ambulocetusnatans • “walking whale that swims” • Skeletons found in Pakistan • Has a long, low body w/ short, powerful limbs • Descended from land-living carnivorous hoofed animals http://www.whale-info.com/bluewhale.html, http://www.bbc.co.uk
Paleontology Problems with the fossil record • Fossils form by chance • Quality of fossils varies • Fossil reconstruction requires thorough knowledge of anatomy • Dating of fossils is achieved through various methods http://eweb.furman.edu
Comparative EmbryologySimilarities in early development Closely-related organisms have similar stages in embryonic development • Tail • Pharyngeal slits/pouches/arches Shared heritage from a common ancestor! http://www.nature.com/nrg/journal/v7/n11/fig_tab/nrg1918_F2.html
Comparative AnatomySimilarities in body structures http://hippie.nu/~unicorn/tut/img/basics/animalanatomy/wing-feathers.jpeg, http://www.uksafari.com/jpeg2/batwing2.jpg, , http://www.bugshop.com.au/images/Butterfly%20Wing.jpg
Comparative Anatomy Similarities in body structures and evolution Divergent evolution or adaptive radiation • Common origin • Descendants appear different externally but are similar internally Convergent evolution • Different origins • Descendants independently evolve similarities when adapting to similar environments
Comparative Anatomy http://itc.gsw.edu/faculty/bcarter/histgeol/paleo2/limbs.jpg
Comparative Anatomy http://www.evolution-textbook.org/content/free/figures/22_EVOW_Art/07_EVOW_CH22.jpg, http://www.carolinabeachtoday.com
Comparative Anatomy Vestigial structures • structures that are of marginal or little use to an organism • e.g. coccyx and wisdom teeth in humans, hipbones and pelvis in whales, anal spurs in pythons and boas • evolution is a remodelling process: ancestral structures may be modified as they take on new roles http://3.bp.blogspot.com/-KAdBIaT796A/Ta-KqBdscqI/AAAAAAAAABQ/KWFe8Ks8Oic/s1600/whale-vestigial-structure.jpg, http://en.wikipedia.org/wiki/Anal_spur
Biochemistry and Molecular BiologySimilarities in chemical compounds • Similarity of DNA b/w individuals of a species:related individuals > unrelated individuals • Two spp. judged to be closely related by other criteria have a proportion of their DNA in common than more distantly related spp. A B C D E http://web.scc.losrios.edu/evanst/, http://andfinally.tv/2009/06/baby-gibbon-mothered-247-by-human/, http://www.datensklaven.de/?tag=animals, http://eco-stride.blogspot.com/2007/10/monkey-mobilized-in-columbia.html, http://www.naturalphotos.com/sekercioglu/madagascar/pages/MG8-TnZoo-RTLE.htm ,
Biochemistry and Molecular Biology *** • Central dogma of mol bio: • DNA RNA proteins • Structure of proteins dictated by DNA sequence • Similar proteins ~ similar DNA sequence ***Hemoglobin: protein that transports O2 in blood
BiogeographyDistribution of species in space and through time Gondwana broke up around 160 MYA eventually forming modern Antarctica, South America, Africa, Madagascar, Australia-New Guinea, and New Zealand, as well as Arabia and the Indian subcontinent http://planet.uwc.ac.za/nisl/biodiversity/loe/images/pic231.gif
Modern species present on a land mass evolved from ancestors that inhabited those regions. • species are not distributed only according to where they can survive http://evolution.berkeley.edu/evolibrary/article/history_16, http://faculty.scf.edu/odaffej/WasDarwinWrong.3/WasDarwinWrongEDIT6.html
Islands have many endemic species that are closely related to species of the nearest mainland or neighboring island. http://myweb.rollins.edu/jsiry/c1x17b-finches.jpg, http://www.galapagosisland.net/galapagos_islands/map.html
Islands have many endemic species that are closely related to species of the nearest mainland or neighboring island. http://bonvito.files.wordpress.com/2010/11/carlito.png
Islands have many endemic species that are closely related to species of the nearest mainland or neighboring island. http://people.eku.edu/ritchisong/birdbiogeography1.htm
Wallace Line - imaginary line separating ecozonesof Asia and Wallacea. West of the line are found organisms related to Asiatic species; to the east, a mixture of species of Asian and Australian origin is present. http://people.eku.edu/ritchisong/wallacesline2.gif
http://people.eku.edu/ritchisong/554images/Zoogeographical_regions.jpghttp://people.eku.edu/ritchisong/554images/Zoogeographical_regions.jpg