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1a) Where are the oldest rocks found on Earth?
The oldest found whole rocks were found in the Nuvvuagittuq greenstone belt in northern Quebec along the east shore of the Hudson Bay. Samples taken from this site indicate an age of 3.8 to 4.28 billion years old, and were confirmed by measuring small variations in isotopic compositions of neodymium and samarium in the rocks.
Older grains of minerals, called zircons, have also been found in Western Australia, with ages of 4.36 billion years.
National Science Foundation (NSF) News – Oldest Known Rock on Earth Discovered: https://www.nsf.gov/news/news_summ.jsp?cntn_id=112299
1b) Are there other types of radiometric dating other than uranium to lead?
There are many types of radiometric dating, such as radiocarbon dating which is based on the radioactive decay of 14C in organic materials, with an accuracy topping out at less than 70,000 years. Similar methods measure the decay of Potassium-40 to Argon-40, Thorium-232 to Lead-208, Samarium-147 to Neodymium-143, and others.
Another way to date materials is by measuring the accumulation of electrons, dislodged by radiation, that have become trapped in imperfections in the crystal structure of the material being measured. Examples of this type of dating are Luminescence and electron spin resonance.
Nature – Dating Rocks and Fossils Using Geologic Methods:
http://www.nature.com/scitable/knowledge/library/dating-rocks-and-fossils-using-geologic-methods-107924044
2a) Have other important transitional fossils have been found?
One set of transitional fossils details the evolution from reptiles to mammals. Dimetrodon lived between 280 million years ago (mya) and 265 mya, had a sail on its back which allowed for partial regula...
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...-resistant CCR5-Δ32 allele formed by a breakdown of the pathocenosis due to the historical Roman expansion?:
http://sharc.sums.ac.ir/icarusplus/export/sites/sharc/unpload/6.pdf
Evaluating plague and smallpox as historical selective pressures for the CCR5-Δ32 HIV-resistance allele: http://www.pnas.org/content/100/25/15276.long
Detection of the CCR5-Delta32 HIV resistance gene in Bronze Age skeletons:
http://www.ncbi.nlm.nih.gov/pubmed/15815693/
6b) What type of mutation lead to this allele?
The CCR5-Δ32 gene is the name of the allele discussed in the video, as eluded to by its name it resulted from a frameshift mutation that occurred in the CCR5 gene resulting in the deletion of 32 base pairs (Δ32).
THURJ | Engineering recombinase enzymes to emulate the CCR5-Δ32 mutation conferring resistance to HIV-1 infection: http://thurj.org/research/2011/02/1238/
When standing on top of the butte, the rock that makes up a majority of the area is quartzite. Quartzite is a metamorphic rock that forms when existing rock is exposed to extreme amounts of heat and pressure (4). The quartzite that is found on Kamiak Butte was formed sometime around 1.47 to 1.4 billion years ago during the Paleozoic period of the Precambrian era. Many of the metamorphic rocks have been fractured and decayed due to physical and chemical weathering, but because quartzite consists of one of the strongest minerals quartz...
More recently than Zeck’s work, Cesare et al. (1997), only divided the xenoliths into two main types: garnet-biotite-sillimanite and spinel-cordierite xenoliths. The quartz-cordierite rocks, distinguished by Zeck (1970), were interpreted as the products of interaction between garnet-biotite-sillimanite xenoliths and blebs of mafic magma and are not recognised. The xenoliths were observed to contain widespread occurrences of rhyolitic glass as...
Mercer, J. M., & Roth, V. L. (2003). The Effects of Cenozoic Global Change on Squirrel Phylogeny. Science, 299(5612), 1568-72. Retrieved from https://search-proquest-com.ezproxy1.apus.edu/docview/213583204?accountid=8289
In the early 1800’s, a new discovery that left paleontologists in awe was the fossil finding of the immeasurable amount of species of reptiles, Ichthyosaurs. Greek for “fish lizards”, these fossils were found all over the world. Because these large aquatic reptiles migrated just as whales do today, paleontologists have had the amazing advantage of collecting fascinating bone fragments throughout the past 177 years. Ichthyosaurs swam the ocean life from about 245 million until about 90 million years ago- approximately the same time dinosaurs ruled the land. The earliest Ichthyosaur fossil findings were in parts of Canada, China, Japan, and possibly Thailand. Countless fossils came from coatings of limestone produced out of the ocean-floor ooze that was predominantly superior at preserving very well facts of the creatures it digested (Perkins 2).
Lewis, Ricki, (2014), Human Genetics, 11th Edition, Chapter 12. Gene Mutation. [VitalSource Bookshelf Online]. Retrieved from
Tree-Ring dating is focused around the rule that the developed rings on specific types of trees reflect varieties in regular and yearly precipitation. Trees from the same species, developing in the same region or environment will be presented to the same conditions, and thus their development rings will match at the point where their life cycles overlap. Tree-ring dating is not used anymore because of the following limitations:
P.Wellman, Ian McDougal,(1974),Cainozoic igneous activity in Eastern Australia, Research School of Earth Sciences, ANU Canberra, Elsevier Scientific Publishing Company,pg 52
Old earth proofs: Most scientists accept these indicators, and many more like them, as proof of an old earth and universe. However, those scientists are forced to make a basic assumption: that naturally occurring processes and fundamental constants in the past behaved in the same way as they do today. For example:
Harte, B. (2010). Diamond formation in the deep mantle: the record of mineral inclusions and
In this lab, eight unidentified mineral samples are the subject of observation and experimentation. The purpose of this lab is to identify the samples based on the observations and experimentation. This paper will identify each of the samples and briefly discuss each one.
...niques, as I mentioned, such as radiocarbon dating. Obviously, the more analytical techniques there are applied to a sample, the greater the accuracy of the results will be. Although this is the case though, on its own dendrochronology is still invaluable to archaeologists. Kuniholm explains:
The mineral diamond can be found in various places. Diamonds are found on planets such as earth, uranus, neptune, saturn, and jupiter. The atmospheres of these planets have the perfect temperature and air pressure conditions to host the carbon in form for the diamond. Diamonds must be in an area with very high temperatures and high pressure for the diamond minerals to be able to form. They need the high temperatures to allow them to become stable ad have a good foundation.
“Willard Libby (a scientist who won the Nobel Prize inn Chemistry) developed radiocarbon dating as a method to measure radioactivity. Carbon-14 is a weakly radioactive isotope of Carbon; also known as radio carbon. Radiocarbon dating cannot be applied to metals, only to organic and selected inorganic materials. The three principal radiocarbon dating methods are: (1) gas proportional counting, (2) liquid scintillation counting and (3) accelerator mass spectrometry.” (Beta Analytic). Radiocarbon dating is the only scientific method to revolutionize man’s understanding of events that occurred in the past and also in the present. It is used to prove and disprove theories in archaeology and other sciences. (Beta Analytic)
Scientists can tell how old something is based on the amount of carbon 14 in a dead object. Carbon dating is accurate if the amount of carbon 14 in the atmosphere remains the same throughout time. The second is if carbon 14 has always decayed at the same speed, and the last is if all living things absorb the same amount of carbon as the atmosphere has in it ("Child Evangelism of Hawaii"). Diamonds are formed when carbon is under a large amount of pressure and heat. When diamonds come from the ground, they don't look shiny.
...ray, beta and gamma rays. He also worked on the rate of decay of uranium atoms, which led to the development of radioactive dating.