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Huge mouth of a small nematode
Sarah Wiggard and Ralf Sommer / Max Planck Institute for Biology Tübingen
Tiny soil insects called nematodes usually feed on bacteria and algae and have small mouths to accommodate their diet. However, when baby nematodes are fed the fungus, their mouths double in size, giving them the ability to cannibalize their mates.
that’s what ralph sommer Researchers at the Max Planck Institute for Biology in Tübingen, Germany, made the discovery while studying the development of predatory soil nematodes. Allody Progaster Sudhouushi.when the larvae are raised Penicillium Some of them ate fungi and cheese and grew into cannibals with giant mouths. “We were shocked,” he says.
The researchers knew that the different mouth shapes seen in this species resulted from different feeding habits. Nematodes that feed on bacteria have narrow mouths, while nematodes that feed on much smaller nematode species have slightly wider mouths. But this extreme variant, which the researchers called “teratostomia,” or Te morphology, had not been previously documented.
Sommer and colleagues investigated the genetics underlying these different mouth shapes and found that all three were controlled by the same sulfatase gene. But that activity only seems to result in a giant, gaping mouth. A. Sudaushi. The species’ complete set of genetic instructions was duplicated only recently in its evolution, Sommer said, so the doubling of gene pairs may have facilitated the origin of the worm’s giant mouth. That’s what it means.
Because the fungi’s diet was low in nutrients and more Te forms were found in high-density conditions, the researchers found that Te forms and their associated cannibalistic habits may have evolved as a response to the stresses of starvation and crowding. That’s what I think.
Nicholas Levis Indiana University points out that a similar phenomenon is seen in several other species. For example, the tadpoles of spadefoot toads and some salamanders can develop into cannibalistic carnivores depending on environmental conditions, Levis says.
But even in such cases, animals often avoid eating their own kind. Te nematodes are nondiscriminatory and prey on genetically identical neighbors. Levis says this is a “surprising finding” that could indicate that the development strategy is “really hopeless.”
“This discovery…made me wonder how much more diverse there is in the natural world than what we see,” Levis says. “How many other hidden ‘monsters’ are there waiting to be discovered under the right environmental conditions?”
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Source: www.newscientist.com