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Saturday, May 30, 2020




GLACIER MICE. RIGHT.
COMPILATION AND COMMENTARY
BY LUCY WARNER
MAY 29, 2020




THIS PHOTO SHOWS “GLACIER MICE,” WHICH ARE WHAT, NOW? IF THIS WEREN’T FROM NPR I WOULDN’T BELIEVE IT. NOTE THE “3 MINUTE LISTEN.” THIS POSES A PROFOUND QUESTION. DOES ROLLING MOSS GATHER ANY STONES? ONE SCIENTIST DID CUT A MOSSY IN HALF AND FOUND NO STONE, JUST A CLUSTER OF ROOTS, BUT THEY PROBABLY DO START GROWING AROUND SOMETHING I WOULD THINK, TO BE SHAPED IN THAT WAY. IT IS POSSIBLE, THOUGH, THAT THERE IS SOME EVOLUTIONARY FUNCTION INVOLVED IN BEING ABLE TO ROLL. AT ONE POINT IN THE ARTICLE IT MENTIONED ACHIEVING ACCESS TO LIGHT ON ALL SIDES, AND THE ENCLOSED ROOTS MIGHT SERVE TO MAINTAIN MOISTURE INSIDE. PERHAPS THE AMOUNT OF AVAILABLE MOISTURE IS VARIABLE. ANYWAY, IT’S INTERESTING.

ONE OF THE POINTS MADE IN THE ARTICLE IS THAT THERE APPEARS TO BE SOME COORDINATED MOVEMENT BETWEEN THE MOUSY BALLS, WHICH NPR’S ARTICLE DESCRIBES AS “HERDLIKE.” THAT MADE ME THINK OF AN ARTICLE I SAW SOME YEARS AGO ABOUT THE FACT THAT SOME PLANTS DO REACT TO THE ENVIRONMENT IN MORE WAYS THAN ONE, THE SENSITIVE PEA, FOR INSTANCE, TO ESCAPE DAMAGING INSECTS. SOME EXUDE CHEMICALS INTO THE SOIL OR THE AIR THAT ACT AS A KIND OF WARNING TO OTHERS OF THEIR SPECIES NEARBY OR PREVENT THE GROWTH OF RIVALS . THAT COMES FROM THE WIKIPEDIA ARTICLE CALLED PLANT COMMUNICATION, THE THIRD ARTICLE THAT APPEARS BELOW.

THERE ARE MANY THINGS THAT WE DON’T KNOW YET ABOUT LIFE ON EARTH, AND SOME ARE HARDER TO PROVE THAN OTHERS. BESIDES THAT FACT, BEING AN EVOLUTIONIST, I BELIEVE THAT AT THIS MOMENT NEW SPECIES ARE COMING INTO BEING, ONE SPECIMEN WITH ITS’ SUCCESSFUL NEW ADAPTATION AT A TIME. ONE ARTICLE I SAW SAID THAT THERE HAVE BEEN NOT ONE, BUT A NUMBER OF SABER-TOOTHED CATS DOWN THROUGH TIME, AND THAT THE CLOUDED LEOPARD FOUND IN PARTS OF ASIA IS A SPECIES WHOSE CANINES ARE BELIEVED TO BE THE LONGEST IN RELATION TO ITS’ BODY WEIGHT OF ALL CATS, INCLUDING TIGERS AND LIONS. IS IT BECOMING THE NEXT SABERTOOTH?


WATCH THIS VIDEO ON THE CLOUDED LEOPARD. IT’S A REALLY BEAUTIFUL ANIMAL, BUT THOSE TEETH!


https://www.youtube.com/watch?v=LmeFu8HMjDQ
Clouded Leopards: Modern Day Saber-Tooths
1,173,326 views • Sep 7, 2018
UPS   27K    DOWNS   688
SHARE   5:20 MIN. DURATION.


NPR'S TAKE ON MOSSY MOUSES.

Herd Of Fuzzy Green 'Glacier Mice' Baffles Scientists
May 22, 2020,  7:09 AM ET
Heard on Morning Edition
Nell Greenfieldboyce 2010

PHOTOGRAPH -- Glacier mice in Iceland, Ruth Mottram

In 2006, while hiking around the Root Glacier in Alaska to set up scientific instruments, researcher Tim Bartholomaus encountered something unexpected.

"What the heck is this!" Bartholomaus recalls thinking. He's a glaciologist at the University of Idaho.

Scattered across the glacier were balls of moss. "They're not attached to anything and they're just resting there on ice," he says. "They're bright green in a world of white."

Intrigued, he and two colleagues set out to study these strange moss balls. In the journal Polar Biology, they report that the balls can persist for years and move around in a coordinated, herdlike fashion that the researchers cannot yet explain.

"The whole colony of moss balls, this whole grouping, moves at about the same speeds and in the same directions," Bartholomaus says. "Those speeds and directions can change over the course of weeks."

In the 1950s, an Icelandic researcher described them in the Journal of Glaciology, noting that "rolling stones can gather moss." He called them "jökla-mýs" or "glacier mice."

This new work adds to a very small body of research on these fuzz balls, even though glaciologists have long known about them and tend to be fond of them.


PHOTOGRAPHS -- Glacier mice can be composed of different moss species.
Timothy Bartholomaus


"They really do look like little mammals, little mice or chipmunks or rats or something running around on the glacier, although they run in obviously very slow motion," says wildlife biologist Sophie Gilbert, also at the University of Idaho.

Each ball is like a soft, wet, squishy pillow of moss. The balls can be composed of different moss species and are thought to form around some kind of impurity, like a bit of dust. They've been seen in Alaska, Iceland, Svalbard and South America, although they won't grow on just any glacier — it seems that conditions have to be just right.

Their motion is what interested Gilbert and Bartholomaus, as well as their Washington State University colleague Scott Hotaling.

"Most people who would look at them would immediately wonder, 'Well, I wonder if they roll around out here in some way,' " says Gilbert. "Tumbleweeds come to mind, which are obviously totally different, but also round and roll around."

She notes that the entire surface of the ball must periodically get exposed to the sun. "These things must actually roll around or else that moss on the bottom would die," says Gilbert.

The possibility of their rolling had been noted by other researchers, who previously observed that the balls sometimes could be found teetering on a pedestal of ice. That pedestal might form as the moss ball insulated the ice underneath it, preventing it from melting as fast as the surrounding ice. Scientists suspected that the ball would eventually tip off of the pedestal and roll away.

To track the motion of 30 moss balls in Alaska, Gilbert and Bartholomaus tagged each one with a little loop of wire that had an identifying sequence of colored beads. Over a period of 54 days in 2009, they tracked the location of each ball. They returned to check on them in 2010, 2011 and 2012.

"By coming back year after year," says Bartholomaus, "we could figure out that these individual moss balls were living at least, you know, five, six years and potentially much, much longer."

The movement of the moss balls was peculiar. The researchers had expected that the balls would travel around randomly by rolling off their ice pedestals. The reality was different. The balls moved about an average of an inch a day in a kind of choreographed formation — like a flock of birds or a herd of wildebeests.

"When we visited them all, they were all just sort of moving relatively slowly and initially toward the south," says Bartholomaus. "Then they all started to speed up and kind of start to deviate toward the west. And then they slowed down again and progressed even farther to the west."


Photograph -- The research team tagged each moss ball with an identifying color sequence of beads to track them over months and years.   Sophie Gilbert


The researchers considered several possible explanations. The first, and most obvious one, is that they just rolled downhill. But measurements showed that the moss balls weren't going down a slope.

"We next thought maybe the wind is sort of blowing them in consistent directions," says Bartholomaus, "and so we measured the dominant direction of the wind."

That didn't explain it either, nor did the pattern of the sunlight.

"We still don't know," he says. "I'm still kind of baffled."

"It's always kind of exciting, though, when things don't comply with your hypothesis, with the way you think things work," says Gilbert.

The work has charmed other glacier scientists who dote on the adorable moss balls.

"I think that probably the explanation is somewhere in the physics of the energy and the heat around the surface of the glacier, but we haven't quite got there yet," says Ruth Mottram, a climate scientist at the Danish Meteorological Institute.

She has long admired glacier mice, which she saw while doing fieldwork in Iceland. "They're extremely engaging when you look at them in a great big mass," she says. "It's very hard not to think of tribbles from Star Trek or something like that."

She expects to see more research on them, as the study of life on glaciers has really taken off in recent years. What was once viewed as a cold, sterile world is now known to be full of bacteria and algae and mysterious life forms.

"I was involved in some research a couple of years ago where we estimated that between 5 and 10% of the melt of the Greenland ice sheet in the summertime is related to the growth of algae and bacteria on the surface," says Mottram.

Indeed, tiny critters including simple worms and water bears can even live inside moss balls, according to one study from 2012.

Nicholas Midgley of Nottingham Trent University says that back then, he and his colleague Stephen Coulson dissected moss balls and put accelerometers inside a number of them. "From that we were able to deduce that they were actually rotating," says Midgley.

They did not track where the balls rolled. "That's obviously where the work that's been undertaken and published on the Root Glacier advances our understanding," says Midgley, who notes that "exceptionally few" scientists have ever studied moss balls.

Bartholomaus says he'd like to go back to Root Glacier again and do a good, long hunt for the moss balls that were tagged over a decade ago. He knows that the spot is still loaded with moss balls.

"I did visit them last year," says Bartholomaus. "I didn't find any tags during a quick cursory look, but the moss balls are still there. Presumably they're still rolling around on the glacier, doing their moss ball thing."

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WIKIPEDIA ON THESE MICE

Glacier mice
From Wikipedia, the free encyclopedia

Glacier mice are colonies of mosses found on some glaciers. They are composed of multiple species of moss[1] and can also host other species, such as nematode worms, springtails, and water bears.[2] Although what preconditions are necessary for glacier mice to form has yet to be determined, they have been observed in Alaska, Chile, Iceland, Svalbard, and Venezuela.[3] In at least some cases, glacier mice apparently reproduce asexually due to the effect of the harsh glacier environment on traditional moss reproduction strategies

Glacier mice are notable for their movement across the ice, which appears to be non-random, taking the form of herd-like behavior. This movement is as yet unexplained,[1] and does not appear to be solely the product of wind, or the direction of a slope. The use of accelerometers has demonstrated that glacier mice do in fact rotate and roll, rather than simply sliding across the ice, over time exposing all of their surfaces.[5] Measurements of glacier mice show that they retain heat and moisture, creating a suitable ecosystem for microorganisms that otherwise could not live on a glacier.[6][7]

Glacier mice were first described in 1950 by Icelandic meteorologist Jón Eyþórsson, who referred to them as jökla-mýs, which is Icelandic for "glacier mice."[8]


PLANT COMMUNICATION

From Wikipedia, the free encyclopedia

Plants can be exposed to many stress factors such as disease, temperature changes, herbivory, injury and more. Therefore, in order to respond or be ready for any kind of physiological state, they need to develop some sort of system for their survival in the moment and/or for the future. Plant communication encompasses communication using volatile organic compounds, electrical signaling, and common mycorrhizal networks between plants and a host of other organisms such as soil microbes,[1] other plants[2] (of the same or other species), animals,[3] insects,[4] and fungi.[5]

Plants communicate through a host of volatile organic compounds (VOCs) that can be separated into four broad categories, each the product of distinct chemical pathways: fatty acid derivatives, phenylpropanoids/benzenoids, amino acid derivatives, and terpenoids.[6] Due to the physical/chemical constraints most VOCs are of low molecular mass (< 300 Da), are hydrophobic, and have high vapor pressures.[7]

The responses of organisms to plant emitted VOCs varies from attracting the predator of a specific herbivore to reduce mechanical damage inflicted on the plant [4] to the induction of chemical defenses of a neighboring plant before it is being attacked.[8] In addition, the host of VOCs emitted varies from plant to plant, where for example, the Venus Fly Trap can emit VOCs to specifically target and attract starved prey.[9]

While these VOCs typically lead to an increase in herbivory resistance in neighboring plants, there is no clear benefit to the emitting plant in helping nearby plants. As such, whether neighboring plants have evolved the capability to "eavesdrop" or whether there is an unknown tradeoff occurring is subject to much scientific debate.[10]

Communication between mycorrhizae and plants:

The host legume roots leaches out a specific kind of proteins called lectins, which diffuse in soil and interact with the glycoproteins of the capsule of rhizobium bacteria. This serves as a measure of communication and directing the growth of bacterial colonies towards host root.

VOLATILE ORGANIC COMPOUNDS

In Runyon et al. 2006, the researchers demonstrate how the parasitic plant Cuscuta pentagona (dodder weed) uses VOCs to interact with various hosts and determine locations. Dodder seedlings show direct growth toward tomato plants (Lycopersicon esculentum) and specifically elicited tomato plant volatiles. This was tested by growing a dodder weed seedling in a contained environment, connected to two different chambers. One chamber contained tomato VOC's while the other had artificial tomato plants. After 4 days of growth, the dodder weed seedling showed a significant growth towards the direction of the chamber with tomato VOC's. Their experiments also showed that the dodder weed seedlings could distinguish between wheat (Triticum aestivum) VOCs and tomato plant volatiles. As when one chamber was filled with each of the two different VOCs, dodder weeds grew towards tomato plants as one of the wheat VOC's is repellent. These findings show evidence that volatile organic compounds determine ecological interactions between plant species and show statistical significance that the dodder weed can distinguish between different plant species by sensing elicited volatile organic compounds (Runyon et al. 2006).

Tomato plant to plant communication is further examined in Zebelo et al. 2012, which studies tomato plant response to herbivory. Upon herbivory by Spodoptera littoralis, tomato plants emit VOCs that are released into the atmosphere and induce responses in neighboring tomato plants. When the herbivory-induced VOCs bind to receptors on other nearby tomato plants, responses occur within seconds. The neighboring plants experience a rapid depolarization in cell potential and increase in cytosolic calcium. Plant receptors are most commonly found on plasma membranes as well as within the cytosol, endoplasmic reticulum, nucleus, and other cellular compartments. VOCs that bind to plant receptors often induce signal amplification by action of secondary messengers including calcium influx as seen in response to neighboring herbivory. These emitted volatiles were measured by GC-MS and the most notable were 2-hexenal and 3-hexenal acetate. It was found that depolarization increased with increasing green leaf volatile concentrations. These results indicate that tomato plants communicate with one another via airborne volatile cues, and when these VOC's are perceived by receptor plants, responses such as depolarization and calcium influx occur within seconds (Zebelo 2012).

TERPENOIDS

[Related chemical to Turpentine, which is the spelling of the brand name. The chemical term is spelled terpene and terpenoids]

The terpenoid verbenone is a plant pheromone, signalling to insects that a tree is already infested by beetles.[11] [Further information: Terpenoid]

Terpenoids facilitate communication between plants and insects, mammals, fungi, microorganisms, and other plants.[12] Terpenoids may act as both attractants and repellants for various insects.  For example, pine shoot beetles (Tomicus piniperda) are attracted to certain monoterpenes  . . . .  produced by Scots pines (Pinus sylvestris), while being repelled by others (such as verbenone).[13] Terpenoids are a large family of biological molecules with over 22,000 compounds.[14] Terpenoids are similar to terpenes in their carbon skeleton but unlike terpenes contain functional groups.  . . . . 

ELECTRICAL SIGNALING

Plants also communicate via electrical signals, which is explored in Calvo et al. 2017. These electrical signals are mediated by cytosolic Ca2+ ions. Cytosolic calcium signals are mediated by hundreds of protein and protein kinases, and many of the signals also induce action potentials in plants. The phloem* of the plant serves as the pathway for electrical communication, and as the plant grows and learns from its past, the phloem becomes increasingly cross linked. Electrical signals may be transmitted to other cells connected by symplasts through plasmodesmata. Plants respond to various environmental cues and elicit electrical responses internally to alter the function of the plant body. This can range from avoiding predation, releasing defense mechanisms, responding to changing temperature, changing growth direction, and sharing nutrients in the soil. This form of memory stored in the plant's phloem allows it to better respond to similar stimuli in the future and shows how electrical signaling allows a plant to communicate with itself and alter its own physiology to better suit certain environmental cues (Calvo et al. 2017).

[LW. NOTE: PHLOEM IS DEFINED AS “the vascular tissue in plants that conducts sugars and other metabolic products downward from the leaves. A PARALLEL STRUCTURE CALLED THE XYLEM CONDUCTS WATER AND NUTRIENTS UP TO THE LEAVES. https://www.lexico.com/en/definition/phloem ]

[XYLEM: “the vascular tissue in plants that conducts water and dissolved nutrients upward from the root and also helps to form the woody element in the stem.  https://www.lexico.com/en/definition/xylem ]

MYCORRHIZAL NETWORKS

Another form of plant communication occurs through their complex root networks. Through roots, plants can share many different resources including nitrogen, fungi, nutrients, microbes, and carbon.  . . . .  This experiment showed that through fungal mycelia linkage of the roots of two plants, plants are able to communicate with one another and transfer nutrients as well as other resources through below ground root networks (Philip et al. 2011). Further studies go on to argue that this underground “tree talk” is crucial in the adaptation of forest ecosystems. Plant genotypes have shown that mycorrhizal fungal traits are heritable and play a role in plant behavior. These relationships with fungal networks can be mutualistic, commensal, or even parasitic. It has been shown that plants can rapidly change behavior such as root growth, shoot growth, photosynthetic rate, and defense mechanisms in response to mycorrhizal colonization (Gorzelak et al. 2015). Through root systems and common mycorrhizal networks, plants are able to communicate with one another below ground and alter behaviors or even share nutrients depending on different environmental cues.


AN ACQUAINTANCE OF MINE WAS A GRADUATE STUDENT IN ZOOLOGY, AND HE DID HIS THESIS ON A STUDY OF THE SLIME MOLD. THAT WAS INTERESTING TO HIM AS A TOOL FOR STUDYING CELL PHYSIOLOGY, BECAUSE THE TYPE OF SLIME MOLD WHICH HE WAS STUDYING HAD NO INTERNAL CELL DIVISIONS; THEREFORE ITS’ BIOCHEMISTRY COULD BE STUDIED AS A SINGLE CELL, BUT UNLIKE A CELL IT WAS LARGE ENOUGH TO OBSERVE CHANGES. CELL CHEMISTRY AT THAT TIME WAS A SUBJECT OF INTEREST. THE REALLY GREAT THING ABOUT IT – OR THE MOST INTERESTING TO ME – WAS THAT THE SLIME MOLD IS ALSO ONE OF THE FEW LIFE FORMS WHICH HAVE CHARACTERISTICS OF BOTH PLANTS AND ANIMALS.

IN THE CASE OF THE SLIME MOLD, HE KEPT IT IN A LARGE DISH ON WET PAPER TOWELS. HE “FED IT” BY DROPPING SEVERAL GRAINS OF ROLLED OATS ON THE TOWEL. IT WOULD MOVE, BY FLOWING MUCH LIKE AN AMOEBA, TO THE OATMEAL AND ENGULF IT. THAT IS NOT TYPICAL “PLANT” BEHAVIOR.

Slime mold
From Wikipedia, the free encyclopedia

Slime mold or slime mould is an informal name given to several kinds of unrelated eukaryotic organisms that can live freely as single cells, but can aggregate together to form multicellular reproductive structures. Slime molds were formerly classified as fungi but are no longer considered part of that kingdom.[1] Although not forming a single monophyletic clade, they are grouped within the paraphyletic group referred to as kingdom Protista.

More than 900 species of slime mold occur globally. Their common name refers to part of some of these organisms' life cycles where they can appear as gelatinous "slime". This is mostly seen with the Myxogastria, which are the only macroscopic slime molds.[2] Most slime molds are smaller than a few centimeters, but some species may reach sizes up to several square meters and masses up to 20 kilograms.[3]

Many slime molds, mainly the "cellular" slime molds, do not spend most of their time in this state. When food is abundant, these slime molds exist as single-celled organisms. When food is in short supply, many of these single-celled organisms will congregate and start moving as a single body. In this state they are sensitive to airborne chemicals and can detect food sources. They can readily change the shape and function of parts, and may form stalks that produce fruiting bodies, releasing countless spores, light enough to be carried on the wind or hitch a ride on passing animals.[4] They feed on microorganisms that live in any type of dead plant material. They contribute to the decomposition of dead vegetation, and feed on bacteria, yeasts, and fungi. For this reason, slime molds are usually found in soil, lawns, and on the forest floor, commonly on deciduous logs.  . . . . 

Today, slime molds have been divided among several supergroups, none of which is included in the kingdom Fungi.

Slime molds can generally be divided into two main groups.

A plasmodial slime mold is enclosed within a single membrane without walls and is one large cell. This "supercell" (a syncytium) is essentially a bag of cytoplasm containing thousands of individual nuclei. See heterokaryosis.

By contrast, cellular slime molds spend most of their lives as individual unicellular protists, but when a chemical signal is secreted, they assemble into a cluster that acts as one organism.

. . . .  

Behavior

When a slime mold mass or mound is physically separated, the cells find their way back to re-unite. Studies on Physarum polycephalum have even shown an ability to learn and predict periodic unfavorable conditions in laboratory experiments.[16] John Tyler Bonner, a professor of ecology known for his studies of slime molds, argues that they are "no more than a bag of amoebae encased in a thin slime sheath, yet they manage to have various behaviors that are equal to those of animals who possess muscles and nerves with ganglia – that is, simple brains."[17]


THIS LAST IS AN ELEGANT LITTLE PIECE ON THE VARIOUS FUNGUS TYPES THAT A STUDENT SCIENTIST HAS FOUND IN FOXFIRE WOODS, WHERE SHE IS SEEKING OUT THE PARTICULAR TYPE OF FUNGUS THAT IS RESPONSIBLE FOR THE GLOW DETECTABLE IN DARK CONDITIONS SUCH AS WOODLANDS AT NIGHT. MY FATHER MENTIONED THIS AS SOMETHING THAT HE HAD SEEN WHEN HE WAS A YOUNG MAN IN MONTGOMERY COUNTY, NORTH CAROLINA. FOXFIRE IS A FORM OF BIOLUMINESCENCE. ANOTHER ARTICLE I SAW CLAIMED THAT SLIME MOLDS ARE NOT ONE OF THE SPECIES THAT GLOW IN THE DARK. MY FATHER SAID, THOUGH, THAT HE WOULD FIND IT ON ROTTING LOGS WHERE THESE SLIME MOLDS TEND TO BE FOUND, AND I HAVE HEARD BEFORE THAT SLIME MOLDS CAN GLOW IN THE DARK. THE QUESTION HAS NOT BEEN PROVEN ONE WAY OR THE OTHER, PERHAPS.

Foxfire Woods Nature Preserve, Allen County, Indiana

“... Working under the assumption that this preserve is named "Foxfire" because there is glowing foxfire fungus here, I was determined to find some.  It had rained recently (finally!) so things were a little more moist and fungus was a bit easier to spot.  However, I had one great disadvantage...it was daytime.  If there was glowing fungus here, I would have to find it in it's non-glowing form, Slime mold plasmodium. 
Like the name implies, slime molds appear as gelatinous "slime." However, the "mold" part of their name is a lie. Slime mold is a protist.  Fungi are molds, but slimes are not. Get it? Me neither. Like fungi, slimes contribute to the decomposition of dead vegetation by feeding on decaying plant matter, as well as tiny microorganisms within. Unlike fungi, slimes move! When food is plentiful, a slime mold exists as a single-celled organism.  But when food is in short supply slime molds congregate and start moving as a single body, called a plasmodium. When the weather is hot and dry for an extended period the plasmodium creates a tough outer layer, as seen above, to protect the cells within until better conditions for growth return.
Predatory slime mold plasmodiums can move at speeds up to 1 millimeter per hour (where's the fire?!) seeking bacteria or fungi to consume. Another difference between slime molds and fungi is that slimes engulf and ingest their food as they flow over it.  If it turns out to be inedible, they eject it.  What an amazing creature!!


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