Outline the method for dating rocks and fossils using radioisotopes Free instant sex cam
Using relative dating the fossil is compared to something for which an age is already known.For example if you have a fossil trilobite and it was found in the Wheeler Formation. There are two main methods determining a fossils age, relative dating and absolute dating.Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages. sapiens: .1 million years – large brain, flat face, reduced teeth, reduced robustness, chin D.5.4 State that adaptations (or micro-evolutionary steps) may occur as the result of an allele frequency increasing in a population over a period of time. p squared = frequency of homozygous dominants p squared = (.463)(.463) = .214 2pq = frequency of heterozygotes 2pq = 2 (.463)(.537) = .497 If there is random mating in a population, the chance of inheriting two copies of the first of the two alleles is (p)(p). erectus: .4 - 1.8 million years – more complex tools so meat significant part of diet and changed teeth. neanderthensis .5 million years – larger brains and bones, larger teeth and jaw, shorter limbs for the cold H. If q = frequency of t allele, q squared = .288 so q = .537 If p = frequency of T allele, p = (1 - q) = .463 The frequency of homozygous dominants (TT) and heterozygotes (Tt) can be calculated.
This distributes the weight of the head over the spine so that modern humans do not need huge necks muscles.
Carbon-14, the radioactive isotope of carbon used in carbon dating has a half-life of 5730 years, so it decays too fast.