In many cases, cells are capable of feats of chemistry that leave human-designed systems in their dust. The problem is that evolution only drives cells that produce the chemicals they need, only in the quantities they need. We design systems to make the chemicals we want and generally take as much as we can produce. Typically, these two things aren't compatible. But some Harvard researchers have figured out a way of getting them into alignment.
It's easy to transplant biochemical pathways into bacteria, at least once you identify the genes involved. At that point, you can have the bacteria produce drugs or other useful chemicals, such as precursors to plastics. The problem is usually that the bacteria aren't happy about it. Producing chemicals generally requires energy, and it siphons off chemical precursors that the bacteria need for their own purposes.
There are two neat tricks that the authors use to induce the bacteria to be happier about being converted into miniature chemical factories. The first is that they figure out how to make the chemical product we want essential to the cell's survival. The second is that they let evolution integrate the new biochemical pathway into the cell.
Bees are disappearing—that much is certain. What's unclear is why. Pathogens and pesticides have been posited as potential causes, as has the loss of bees' preferred floral resources. This last reason has intuitive appeal: wildflowers are disappearing because of agriculture, and bees rely on the pollen and nectar in flowers, so the loss of flowers should be causing the loss of bees.
But a demonstration of this seemingly simple idea has been hard to come by. Different species of bees rely on different plants—the bee species that are disappearing have never been analyzed in terms of taste for the plants that are disappearing to see if they match up. And, once the bees or plants are gone, it's hard to figure out what relationship (if any) they might have had. Pesky details.
Researchers in the Netherlands have gotten around this problem by examining museum specimens of bees to figure out which bees like which flowers. They've demonstrated that the bee species that have declined are in fact those that like the pollen from flower species that have also declined.
If you really think about it, a great many things go into a painting. There’s the artist’s vision, sure, but there’s also the pigments and properties of the paint, the mixing of the paints on the palette, the canvas and frame, the types of brushes used, and the physical skill of the painter. Landscapes, likewise, are determined by many factors (even if they never appear in a painting). But for landscapes, a complex system of factors interacts dynamically, continually evolving and producing a masterpiece every step of the way.
The Himalayas are an astoundingly grand landscape; we call them “the roof of the world.” You could simply describe them as the crumpled product of the collision between the Indian and Eurasian tectonic plates, but that would be about as bland as describing the contents of the Louvre as “paint.” Each peak and valley has been slowly sculpted by a collaboration of geologic processes. Researchers have recently uncovered evidence about one of these processes, something with the inartistic name of "tectonic aneurysm."Floating peaks
It’s reasonable to assume that, in a place like the Himalayas, tectonics pushes a mountain up even as erosion shaves it down. The faster the mountain pushes upward, the harder erosion works to keep it in check. That's because the peaks extend into colder elevations where ice can wedge apart cracks or form rock-grinding glaciers and steepening slopes that drive faster-flowing streams.
At the centers of some massive galaxies, supermassive black holes power incredibly bright objects called quasars. Black holes gobble up matter so quickly that the infalling matter heats up from friction and emits light. While this disk of accreting matter is incredibly bright on its own, the black hole has another source of light: jets erupt from the poles of the black hole, shooting particles at speeds approaching that of light. These jets are incredibly bright—possibly brighter than the accretion disk.
It’s not known for sure what causes the jets. It’s thought that the black hole’s spin and mass interact with the magnetic field near the black hole to accelerate the particles. While some evidence supports this model, it's been difficult to test, mainly because scientists lacked a full knowledge of how bright the accretion disks is. But a new study of a sample of blazars (quasars with jets that point toward Earth) shows a clear correlation between the jets' power and the accretion disk’s brightness. This suggests that the magnetic field is a factor in producing the jets.
The researchers examined 217 blazars using data obtained by the Fermi observatory, looking for some relationship between the jets’ power and the accretion disk. Blazars are useful because with a blazar, we get direct light from both the accretion disk and the jet, since the latter is pointed toward us. And we can tell which is which, because light from the jet is mostly in the form of gamma rays, while the accretion disk produces a broader emission spectrum.
If you know how to do something and people around you start doing it differently, you have two options: stick to what you know, or change to use their strategy. If the new strategy is more efficient than yours, or gets better results, it’s a no-brainer, so you switch. But if it’s exactly as efficient and produces the same results, the decision to switch is based on another factor—conformity.
We know that we have a tendency to fall in line with those around us, sometimes even when this results in obvious mistakes. This tendency can explain why human culture varies so widely among different societies, but is so similar within groups. Our closest primate relatives don’t have cultural variation to the same degree, so what makes humans different?
Previous research on non-human great apes has shown that they learn from their peers. However, what hasn’t been established is whether this process is similar in humans and non-humans, including when the learning involves overriding existing habits. A group of researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, recently found that human children are more likely than chimpanzees and orangutans to change their behavior to conform to their peers.