Still driving the bus, we knew that raindrops drained and spread out on the glass from the other side. Then we grew up and learned that oil droplets in water merge together, forming larger drops until you gather everything into one large sphere. Intuition tells us that the drops of love gather, though we don't know why. (They do this to minimize surface area because their component molecules prefer a chemical company his own kind, and not the surrounding liquid).
Not long ago, scientists have discovered that this well-known dynamics of drops is only part of the story. Drops that "chemically active", use sunlight or some other source of energy for the constant of cyclization of the molecules in the liquid environment behave in unexpected ways, which may have played a crucial role in the birth of life on Earth.
Unlike the usual drops of our youth, active drops grow to about the size of the cells and cease to grow; they also spontaneously share, producing child drops. The hypothesis was first put forward in 1924 and recently resuscitated by a group of biologists and physicists in Dresden, Germany: a drop of liquid in its primeval soup of the early Earth were primitive precursors of the first cells. As these active-drop "protocells" divided and multiplied, they began to push evolution, making them more difficult and the resulting growth of living cells.
The Physics division active drops so far studied only on paper and in various models, while preparing experiments. However, something like this predicted effect may have been observed decades ago.
The Biochemist David Diemer, University of California, Santa Cruz — a prominent supporter of the theory "first membrane" . Dimer believes that protocells were supposed to have a membrane of fatty acids, such as those that surround the modern cell — structure more complex than drops, do not have obvious methods of reproduction. But when the Dimer was reading predictions of the Dresden group on the theme of active drops and protokletos hypothesis, he remembered "something remarkable" that he saw once in drops, extracted from the Murchison meteorite, which crashed in Australia in 1969.
In 1980-ies of the Dimer found membranebased molecules in this outer stone — a possible sign that these chemicals were abundant on the early Earth, as required by the hypothesis of the "first membrane". But Dimer made another observation, which never wrote. He stared at the oily hydrocarbon pigments extracted from the Murchison sample, under a microscope. "When I turned on the light in the microscope, I looked at these drops with an unexpected side — they seemed to be alive," he says. "They started to move through the environment — the environment was just a glass plate, of course — and move the material inside. And then the scope was extended and divided into two small spheres that then has spread".
This behavior is "so much interested" Dimer thirty years ago that he shot it. And discussing research Dresden group this month, Dimer said, "I Think I should write these guys and tell them about it."
Frank Julicher, author of the new work with pleasure . "Very interesting," he said in a letter to the Dimer. A little reflection on the physics of extraterrestrial drops, Julicher said, "the Flow and "division" in this painting arise from the process of active wetting". The light triggers a chemical reaction that produces molecules that moisten the substrate of the microscope, he explained. This, in turn, creates a gradient of surface tension drops and the material starts to circulate and move. "The physics is somewhat different from the separation of droplets, which we studied in our work, that occurs without a wetting," says Julicher, adding that a key distinction I learned about his team that their drops were chemically active and stationary at the same time — like cells.
Both mechanisms dividing drops at the moment are poorly studied and both are new examples of so-called "unbalanced" physical behavior. Even if the old entry of the Dimer shows a different effect, different from that studied the Dresden scientists, this may indicate that the division of the drops is more common than was known, and therefore could play a role in the origin of life.
In any case, it's not every day you see this.