Roca dels Bous (archaeological site) interesting archaeological site indeed. Furthermore, it is to be noted that the samples used for the 14C AMS dating were obtained from deep strata at the site. The oldest Neanderthal sites known in the nearby areas date back to around 40,000 BP. The first settlements attributed to “anatomically modern” Homo sapiens sapiens in Northern Spain are dated around 39,000-38,000 BP. All this would suggest that Neanderthals could have persisted in this particular area longer than previously believed, preceding the arrival of the first Homo sapiens to the area. Research work began in 1988. This wide period of time has contributed
Isotope (counting as stable), and 26 elements have only a single stable isotope (of these, 19 are so-called mononuclidic elements, having a single primordial stable isotope that dominates and fixes the atomic weight of the natural element to high precision; 3 radioactive mononuclidic elements occur as well). In total, there are 253 nuclides that have not been observed to decay. For the 80 elements that have one or more stable isotopes, the average number of stable isotopes is 253/80 = 3.1625 isotopes per element. The proton:neutron ratio is not the only factor affecting nuclear stability. It depends also on evenness or