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11 - Life - IV. (other interesting things). Interesting Extremophiles. The Archaebacterium Methanosarcina. Methanogens convert CO 2 to CH 4 Acidophiles - live in acidic conditions Thermophiles - love the heat!.
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11 - Life - IV (other interesting things)
Interesting Extremophiles The Archaebacterium Methanosarcina • Methanogens • convert CO2 to CH4 • Acidophiles • - live in acidic conditions • Thermophiles • - love the heat! Helicobacter pylori bacteria use H in stomach acid (see more at cellsalive.com Found in thermal hot springs & near black smokers
Endoliths - Live Inside Rocks • Cryptoendolyths • in surface rocks • Subsurface Endoliths • groundwater aquifers & caves • Deep-Biosphere Endoliths • - down to 3 km! Some found in rocks in Antarctica Many are “chemical autotrophs” extracting nutrients from rocks “bacillus infernus”
Bacterium living without any other organisms deep in a South African gold mine. Natural radioactivity in the ground breaks apart water allowing the oxygen to react with iron sulfide minerals to make iron sulfites, which it can eat. (See Science News Nov. 8, 2008 - Photo by Greg Wanger and Gordon Southam, University of Western Ontario
Mitochondrial DNA & Human Origins Mitochondrial DNA inherited from the female (through egg) “The genetic makeup of the rest of the world is a subset of what’s in Africa” - Kenneth Kidd Y-chromosome only from/in males Both graphics from National Geographic
Obsolete Adaptations • Over time, some adaptations are no longer required - sometimes vestigal remains (or even lost) • Leg bones in whales (baleen, humpback, sperm), some of which have digits • Wings of flightless birds • Etc.
“Walking Seal” remains found in Canadian Arctic April 23 (2009) Nature Legs of a terrestrial animal, a seal-like skull and webbed feet
253 Million Year Old Cellulose Extracted from drop of water trapped in halite (salt) deposit. See: http://www.sciencenews.org/articles/20080405/fob5.asp
Feathered Dinosaurs Dino-DNA closely resembles that of today’s chickens! Soft T. rex tissue extracted. See: http://www.physics.uc.edu/~sitko/PHYS122/DinoDNAandChickens.pdf
(remember the mitochondria?) Endosymbiosis Amoeba uses bacterial invaders: http://evolution.berkeley.edu/evolibrary/article/_0/endosymbiosis_01
Evolution in a Petri Dish 152 colonies infected with bacterium - 1 survived and even eats the “killer”. Cost: not as active, uses oxygen less efficiently - apparently uses alternative respiration enzymes. See: http://www.physics.uc.edu/~sitko/PHYS122/EvolutionPetriDishFull_sm.pdf Almost a new species?
Lateral (Horizontal) Gene Transfer from a bacterium into insects and nematodes: http://www.sciencemag.org/cgi/content/abstract/1142490 http://en.wikipedia.org/wiki/Horizontal_gene_transfer
Bacteria can transfer antibiotic resistance to others! http://www.textbookofbacteriology.net/resantimicrobial.html VERY bad for spread of infections in hospitals!