Slime mold what is it

Slime molds are relatively easy to study, as protozoa go. They are macroscopic organisms that can be easily manipulated and observed. There are more than species of slime mold; some live as single-celled organisms most of the time, but come together in a swarm to forage and procreate when food is short. Others, so-called plasmodial slime molds, always live as one huge cell containing thousands of nuclei.

Most importantly, slime molds can be taught new tricks; depending on the species, they may not like caffeine, salt or strong light, but they can learn that no-go areas marked with these are not as bad as they seem, a process known as habituation.

Studies of the behavior of primitive organisms go all the way back to the late s, when Charles Darwin and his son Francis proposed that in plants, the very tips of their roots a small region called the root apex could act as their brains. Herbert Spencer Jennings, an influential zoologist and early geneticist, made the same argument in his seminal book Behavior of the Lower Organisms.

However, the notion that single-celled organisms can learn something and retain their memory of it at the cellular level is new and controversial.

Traditionally, scientists have directly linked the phenomenon of learning to the existence of a nervous system. She believes that such organisms might clarify how learning first evolved. Slime molds crawl slowly, and they can easily find themselves stuck in environments that are too dry, salty or acidic. Dussutour wondered if slime molds could get used to uncomfortable conditions, and she came up with a way to test their habituation abilities. It refers to how an organism responds when it encounters the same conditions repeatedly, and whether it can filter out a stimulus that it has realized is irrelevant.

For humans, a classic example of habituation is that we stop noticing the sensation of our clothes against our skin moments after we put them on. We can similarly stop noticing many unpleasant smells or background sounds, especially if they are unchanging, when they are unimportant to our survival.

For us and for other animals, this form of learning is made possible by the networks of neurons in our nervous systems that detect and process the stimuli and mediate our responses. But how could habituation happen in unicellular organisms without neurons?

Starting in , Dussutour and her team obtained samples of slime molds from colleagues at Hakodate University in Japan and tested their ability to habituate. To reach the oatmeal, the slime molds had to grow across gelatin bridges laced with either caffeine or quinine, harmless but bitter chemicals that the organisms are known to avoid.

After two days, the slime molds began to ignore the bitter substance, and after six days each group stopped responding to the deterrent. Similar symptoms can develop on woody and herbaceous plants after they have been covered by the superficial growth of the fungus.

Although slime molds are not pathogenic to plants, they occasionally cause indirect injury when they cover and shade plant tissues for extended periods of time. Slime molds have no direct economic importance. Slime molds are fungi in the class Myxomycetes.

These are cosmopolitan organisms that feed on bacteria, protozoa, and other tiny organisms. As is the case with other fungi, slime molds reproduce by spores. Once the spores germinate, they go through several developmental stages which eventually result in a feeding stage called a plasmodium.

A plasmodium is a multinucleate mass of protoplasm which results from the fusion of amoeba-like cells. Wednesday, Nov The Latest. World Agents for Change.

Health Long-Term Care. For Teachers. NewsHour Shop. About Feedback Funders Support Jobs. Close Menu. Email Address Subscribe. Yes Not now. They are not a true fungus. And they engulf their food, mostly bacteria. The slime mold that typically appear on mulches are from the genus, Fuligo. The brightly color blobs usually appear and may spread around mulched beds when there is high humidity and relatively warm temperatures. In Texas, we typically hear of slime molds in the spring and occasionally in the summer in highly irrigated shade areas.

Slime mold can appear to be bright yellow to red. As they begin to dry out, these colors fade to brown and tan.