Field of Science

Evolution highlights XI

Speciation happens in coral reefs
This makes is all the more troubling that climate change are destroying the reefs, which may all be gone by 2050.

Oldest Land-Walker Tracks Found--Pushes Back Evolution
This does not make Tiktaalik uninteresting as a transitional fossil, but merely tells us that tetrapods evolved earlier than previously thought.

Evolutionary Surprise: Eight Percent Of Human Genetic Material Comes From A Virus
Not the only study that suggests that incorporating virus genetic material into our DNA has been important in our evolution.

Lately several items in the news about the evolution of resistance to herbicides and other drugs to control pests:

US-German team measures how quickly genomes change

On the other hand, the new findings easily explain why weeds become quickly resistant to herbicides. In a large weed population, a few individuals might have a mutation in just the right place in their genome to help them withstand the herbicide. "This is in particular a problem because herbicides often affect only the function of individual genes or gene products," says Weigel. A solution would be provided by herbicides that simultaneously interfere with the activity of several genes.

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"Everything that is genetically possible is being tested in a very short period," adds Lynch, emphasizing a very different view than perhaps the one we are all most familiar with: that evolution reveals itself only after thousands, if not millions of years.
Disinfectants Cause Some Bacteria to Adapt, Thrive
The research team focused on Pseudomonas aeruginosa, a bacterium responsible for a range of infections in people with weakened immune systems. When the scientists added increasing amounts of disinfectant to P. aeruginosa cultures, the bacteria adapted to survive not only the disinfectant but also the antibiotic called ciprofloxacin.

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"What is more worrying is that bacteria seem to be able to adapt to resist antibiotics without even being exposed to them."
What??? I just saw this, and I really must find out what the heck this is supposed to mean. How it is possible to adapt something that the organism has never been exposed yet is a mystery.

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