Apparently myxos have little impact on humans "for good or ill," notes Stephenson. For Mitchell, "their failure to have any discernible commercial value for humans" is why he studies them. But others have appreciated these beautiful forms of life. The medieval artist Hieronymus Bosch, known for his fantastic paintings of Heaven and Hell, was also a meticulous painter of natural history.
In his painting Garden of Earthly Delights , one scientist found representations of at least 22 species of slime molds. There are two kinds of slime molds: the acellular, of which there are today 1, known species; and the cellular, of which about 70 species have been identified. The marked difference between them is that the acellular slime molds have many nuclei but only one cell wall during the plasmodial stage, while the cellular ones are composed of individual cells.
In any case, slime molds, said to be a billion or so years old, could be one of the first organisms formed by independent cells joining together.
Some are famous as lab "animals," like the cellular slime mold Dictyostelium , which has been figuring in genetics and uncovering the origins of complex organisms like ourselves, in whom many once independent cells gave up their separate identities. To reach the spore state, the cellular slime molds start out as single cells that communicate by exuding certain chemicals, among them acrasin. This compound is a call for fellow cells to aggregate into a tiny slug, rather than a plasmodium, that then crawls around until it proceeds to stalkdom.
The acellular may conquer mazes, but Bonner maintains that cellular slime molds are hardly slouches. And apparently they are just as hell-bent on getting their slugs to a feeding ground of "bacteria. We slog to the apex of Clingmans Dome and onto the Appalachian Trail. He has described it as having "the false but iridescent colors of the hummingbird. Schnittler first discovered this myxo in northern Germany and just this past year uncovered another patch here in the Smokies, on a similar rock face, an unusual habitat for eastern North America.
For two such tiny myxos of the same rare species to exist some 5, miles apart seemed to me to hint of an ancient lineage. Their ancestors may have lived together on the supercontinent Pangea, been carried apart by plate tectonics, and been dispersed still farther on high-altitude winds. They are eaten by many small animals there are little, shiny, brown beetles apparently feeding — and cavorting — in the pink slime mold , and some are said to be edible by humans. And when they are chopped up, they reassemble and remember.
These giant cells can grow to square meters in area, though most are a few square centimeters or inches instead. Their potential for enormous size explains the movement and flowing "veins" seen in the mesmerizing video and GIF, said Audrey Dussutour, a researcher at Universite Paul Sabatier in France who studies slime molds. This liquid movement of the cell's cytoplasm pushes the cell forward, she said.
The cytoplasm veins also carry nutrients throughout the organism. Unlike most cells, those of P. This makes slime molds intriguing objects of study for scientists, who have found that the organisms can store "memories" of past events in their slimy trails , despite being entirely brainless. This cell reacts to light and chemicals and uses these sensitivities to feed and move away from substances it considers dangerous.
This stage also can produce a resistant structure sclerotium to escape unfavorable conditions. Unknown cues start the reproductive process. The plasmodium crawls upward to a lighted, dry area. The entire surface of the plant or turf is often covered by slime mold, creating a dramatic appearance. The plasmodium then clumps and produces grayish-white sporangium plural sporangia , an environmentally resistant structure that produces spores Dickinson, Nelson, and Weis, About the size of a pinhead, they grow perpendicular to the surface of the leaves.
Once started, fruiting does not stop. The high area provides a launching point for the haploid spores, so they can travel farther. In most cases, control is not necessary. As soon as the area dries, the slime mold disappears. In unusual cases, the layer of crusty growth may become heavy enough to shade grass blades and cause yellowing. You can remove slime molds from lawns by mowing and collecting the clippings, poling with a switch of bamboo, or pulling a garden hose across the affected area.
You can raise slime molds. Different types of decaying wood and forest debris can be collected and kept in a humid place or box; the different types of slime molds growing from them can be used for many experiments. The sporangia can be collected and stored in a refrigerator for later use.
You can grow slime molds in petri plates or storage containers that hold moisture. Place a moistened not wet , heavy piece of porous paper filter paper in the container. Place a piece of sporangium on the moistened paper and close the top. You will need to check the chamber every day and moisten it if needed with drops of water. You will see the hatched and active plasmodia. Then, add premoistened rolled oats to the surface of the paper in the pattern you wish.
If you do not feed your plasmodia, they may form the resting sclerotium, which you can save. Slime molds are extremely efficient in their movements——so much so that they can be used to design efficient transportation networks and computers.
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