A team of scientists has developed a method that yields, for the first time, visualization of a gene amplifications and deletions known as copy number variants in single cells.

Significantly, the breakthrough, reported in the journal PLoS Biology, allows early detection of rare genetic events providing high resolution analysis of the tempo of evolution. The method may provide a new way of studying mutations in pathogens and human cancers.

“Evolution and disease are driven by mutational events in DNA,” explains David Gresham, an associate professor in New York University’s Department of Biology and the study’s senior author. “However, in populations of cells these events currently cannot be identified until many cells contain the same mutation. Our method detects these rare events right after they have happened, allowing us to follow their trajectory as the population evolves.”

Neoliberalism slows down evolution! Just kidding…or am I? 🧐😁🤣🙈.

Like other organisms, bacteria constantly have to fight to survive in hostile living conditions. Together with colleagues in Finland, researchers at the Max Planck Institute for Evolutionary Biology in Plön have discovered that bacteria adapt to their environment more slowly and less efficiently as soon as they are exposed to two stress factors rather than one. This is due to mutations in different genes. The slower rate of evolution led to smaller population sizes. This means that evolution can take divergent paths if an organism is exposed to several stress factors.

Bacteria rarely live alone; they are usually part of a community of species that is exposed to various stress factors. They can often react to these factors by adapting to new environmental conditions with astonishing speed. Antibiotics that enter soil and water via waste water and accumulate there in low concentrations can trigger the evolution of resistance in bacteria – even though these concentrations are so low that they inhibit bacterial growth only slightly or not at all. However, bacteria do not only have to fight antibiotics; they also have to deal with predators. This is why they often grow in large colonies that cannot be consumed by predatory organisms.

Typically, scientists investigate the effects that a single stress factor has on an organism. Researchers at the Max Planck Institute for Evolutionary Biology in Plön and the Universities of Helsinki and Jyväskylä, Finland, have now investigated the question of how microorganisms behave when they are confronted with more than one stress factor. “We simulated natural environmental conditions in the lab and exposed bacteria to both predators and antibiotics. This allows us to estimate how likely it is to find evolution of resistance to antibiotics outdoors,” explains study leader Lutz Becks.

I just love it when the reductionists are wrong…again. I can not help myself. bigsmile

University of Nebraska-Lincoln researchers have found revolutionary evidence that an evolutionary phenomenon at work in complex organisms is at play in their single-celled counterparts, too.

Species most often evolve through DNA mutations inherited by successive generations. A few decades ago, researchers began discovering that multicellular species can also evolve through epigenetics: traits originating from the inheritance of cellular proteins that control access to an organism’s DNA, rather than genetic changes.

Because those proteins can respond to shifts in an organism’s environment, epigenetics resides on the ever-thin line between nature and nurture. Evidence for it had emerged only in eukaryotes, the multicellular domain of life that comprises animals, plants and several other kingdoms.