Anatomically modern humans and all other life that has existed on the planet first came about from the single-celled microorganisms that emerged approximately 4 billion years ago. Through the processes of mutation and natural selection, all forms of life developed, and this continuous lineage of life makes it difficult to say precisely when one species completely separates from another. In other words, scientists still debate when a human became a human rather than the ancestor species that came before. Around 1. Instead, they are found across Africa and parts of mainland and insular Asia. This is the first species of Homo to be found outside Africa Rightmire Features of H.
The Brachiopoda, a major group of the Lophotrochozoa, experienced a rapid early evolutionary diversification during the well-known Cambrian explosion and subsequently dominated the Palaeozoic benthos with its diversity and abundance.
Eight years after DNA barcoding was formally proposed on a large scale, CO1 sequences are rapidly accumulating from around the world. While studies to date have mostly targeted local or regional species assemblages, the recent launch of the global iBOL project International Barcode of Lifehighlights the need to understand the effects of geographical scale on Barcoding's goals. Sampling has been central in the debate on DNA Barcoding, but the effect of the geographical scale of sampling has not yet been thoroughly and explicitly tested with empirical data. Here, we present a CO1 data set of aquatic predaceous diving beetles of the tribe Agabini, sampled throughout Europe, and use it to investigate how the geographic scale of sampling affects 1 the estimated intraspecific variation of species, 2 the genetic distance to the most closely related heterospecific, 3 the ratio of intraspecific and interspecific variation, 4 the frequency of taxonomically recognized species found to be monophyletic, and 5 query identification performance based on 6 different species assignment methods.
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