1a) Where are the oldest rocks found on Earth? The oldest whole rocks found were found in the Nuvvuagittuq greenstone belt in northern Quebec along the eastern shore of Hudson Bay. Samples taken from this site indicate an age of 3.8 to 4.28 billion years and were confirmed by measuring small variations in the isotopic compositions of neodymium and samarium in the rocks. Grains of older 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=1122991b) Are there other types of radiometric dating other than leaded uranium? There are many types of radiometric dating, such as radiocarbon dating which is based on the radioactive decay of 14C in organic materials, with a maximum accuracy of 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, etc. Another way to date materials is to measure the accumulation of electrons, dislodged by radiation, which are 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-1079240442a) Have other important transitional fossils been found? A 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 partial regulation...... middle of paper ...... trained resistant CCR5-Δ32 allele by a breakdown of pathocenosis due to historical Roman expansion? resistance allele: http://www.pnas.org/content/100/25/15276.longDetection of the HIV resistance gene CCR5-Delta32 in Bronze Age skeletons: http://www.ncbi. nlm.nih.gov/pubmed /15815693/6b) What type of mutation led to this allele? The CCR5-Δ32 gene is the name of the allele discussed in the video, as its name escapes it, it results from a frameshift mutation that occurred in the CCR5 gene, resulting in the deletion of 32 base pairs (Δ32).THURJ | Generate recombinase enzymes to emulate the CCR5-Δ32 mutation conferring resistance to HIV-1 infection: http://thurj.org/research/2011/02/1238/