}

Advancing evolution by reducing the genome

2005/05/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

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The single-celled microorganism Prochlorococcus is the smallest form of life of marine phytoplankton and its genome is the smallest of the organisms that produce oxygen through photosynthesis. They have now discovered, moreover, that the more evolved their lower genome is. Despite being so small,
it is the most abundant photosynthetic organism on Earth. It is also essential in the food chain, as it lives in marine areas very scarce in food, occupying a place inappropriate for others and filling it with life.

Researchers have decoded the genomes of three species, one of which lives on the skin and the other two at a less clear depth. Comparing the genomes, they discover that the genome of what lives in the skin is much smaller than that of others. In fact, this species is the youngest in evolution, born 150 million years ago, and has only 1,700 genes. The largest has 2,300. Of these, 1,300 are equal in both.

According to scientists, those with the lowest genome in evolution have advanced. Because it is a small DNA, the cell itself does not have to be so large, which seems to be an advantage to be able to develop in places where there is little food. This is the first time they see how the genome of a living organism decreases.