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30 million kilometers may sound like a great distance, but in astronomical terms that is not very far at all, and it is important to remember that distance is measured from the exact center of the meteor swarm.This summer, Earth will approach within 30,000,000 km of the center of the Taurid swarm, the study says. That would be Earth's closest encounter with the swarm since 1975 and the best viewing opportunity we'll have until the early 2030s.
There are simply better weather conditions for observing the moon than in Germany.
How do new genes and functional proteins arise and develop? This is one of the most fundamental issues in evolutionary biology. Two different types of mechanism have been proposed: (1) new genes with novel functions arise from existing genes, and (2) new genes and proteins evolve from random DNA sequences with no similarity to existing genes and proteins. In the present study, the researchers explored the latter type of mechanism: evolution of new genes and proteins from randomised DNA sequences - de novo evolution, as it is called. It is fairly easy to understand that when a gene already exists, it can be modified and acquire a new function. But how does "nothing" turn into a function affording a small advantage that is favoured by natural selection? [Emphasis added.]Upon reading this news, however, one finds another case of artificial selection. True, they started with 500 million randomized sequences, but the scientists selected the goal: finding polypeptides able to confer antibiotic resistance. While they were delighted to see successes out of their sample, their experiment had nothing to do with natural selection. Even worse, they only tested short polypeptides 22-25 amino acid residues long. The sequence space rises exponentially with polypeptide length, ensuring that even small proteins of 100 aa would be vastly outnumbered by useless ones.
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