Category: protists

ZeFrank on slime molds

February 2, 2023 • 1:45 pm

I can’t even give you a position of slime molds on the tree of life because their constituents are so diverse (a few of my science friends work on them). This is from Wikipedia:

Slime mold or slime mould is an informal name given to several kinds of unrelated eukaryotic organisms with a life cycle that includes a free-living single-celled stage and the formation of spores. Spores are often produced in macroscopic multicellular or multinucleate fruiting bodies which may be formed through aggregation or fusion. Slime molds were formerly classified as fungi but are no longer considered part of that kingdom. Although not forming a single monophyletic clade, they are grouped within the paraphyletic group 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. Most slime molds are smaller than a few centimetres, but some species may reach sizes up to several square metres and masses up to 20 kilograms.

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 and fungi. For this reason, slime molds are usually found in soil, lawns, and on the forest floor, commonly on deciduous logs. In tropical areas they are also common on inflorescences and fruits, and in aerial situations (e.g., in the canopy of trees). In urban areas, they are found on mulch or in the leaf mold in rain gutters, and also grow in air conditioners, especially when the drain is blocked.

ZeFrank’s videos are getting more and more biological and more and more engaging. This new one has some spectacular video, for these creatures have some bizarre behaviors. (There’s an ad from 5:33 to 6:45.) These things can even learn mazes and teach humans how to make efficient transportation routes!

If you don’t think biology is fascinating after watching this, you need to polish up your sense of wonder.

Readers’ wildlife photos

September 12, 2022 • 8:00 am

Today’s photos are of fungi (one is actually a protist), and come from reader Leo Glenn (there’s also a moggy for lagniappe). Leo’s captions and IDs are indented, and you can enlarge the photos by clicking on them.

I’m responding to your call for wildlife photos. Here is a selection of fungi, a weather photo, and an obligatory moggy.

A group of Shaggy Parasol mushrooms (Chlorophyllum rhacodes) growing in a pile of dung. Perhaps your readers can guess the species responsible for such a prodigious pile of poo (hint: it’s appropriately alliterative). The answer is the North American Porcupine (Erethizon dorsatum). This photo was taken at the entrance to its den.

A first-time find for me, as it is a relatively uncommon mushroom here in the Pennsylvania woods. The Slender Roundhead (Leratiomyces squamosus). A synonym for this species is Psilocybe squamosa, and it is included in Paul Stamets’ book, Psilocybin Mushrooms of the World, though its active psilocybin content is thought to be negligible.

Speaking of Paul Stamets, here are a couple specimens of Tinder Fungus, also called Tinder Conk and Hoof Fungus (Fomes fomentarius). In addition to having been used by many cultures for thousands of years as tinder to start fires, it can also be made into faux leather, which can then be shaped into various things, including hats. Stamets, the famous mycologist, has a hat made from the fibers of this fungus that he can be seen wearing at most of his public appearances. It is also known as the Ice Man Fungus because it was one of two species of fungus (the other being Birch Polypore, Piptoporus betulinus) found on Ötzi, the 5,300-year-old natural mummy discovered in 1991 in the Alps on the border between Austria and Italy.

My son, fascinated that a mushroom could both be used as tinder and fashioned into faux leather, experimented on some (by pounding on it with a mallet for half an hour), and found that it did indeed come to resemble leather both in feel and appearance.

Old Man of the Woods (Strobilomyces strobilaceus), among some club mosses, the taller of which I believe is Princess Pine (Dendrolycopodium obscurum). I’m not sure of the shorter one, other than that it is probably one of the bristly club mosses.

Chocolate Tube Slime Mold (Stemonitis splendens). Slime molds were formerly classified as fungi, though they are now placed within the kingdom Protista.

Technically not a wildlife photo, as these are some that I cultivated. These are young Nameko mushrooms (Pholiota microspora). They are a staple in miso and other soups and stews in Japan, but virtually impossible to find fresh here in the United States, unless you grow your own.

I remember a while back you posted some photos of mammatus clouds. This was taken in front of our house this past spring.

I felt obliged to include a moggy. This is my daughter’s cat, Miso, whom we nicknamed the Luxury Model, for reasons which I imagine are obvious. (My son’s cat is nicknamed the Stealth Model.)

 

A Venn diagram for the anxious

June 30, 2021 • 2:15 pm

I have a theory, which is mine, that on average Jews tend to have higher levels of anxiety than non-Jews, but my evidence is only anecdotal. and includes self-observation. I could even give reasons why this might be the case: the history of Jews being driven out of their homes, persecuted, denigrated, demonized, or killed, which might lead one to have a “glass half empty” attitude. I certainly instantiate this tendency, and tend to worry needlessly, especially when it involves ducks. (I realize, of course, that there are plenty of anxious goyim.)

But I’ve been helped by this diagram that a member of Team Duck drew for me when I was being too anxious about the ducks.(I’ve fancied it up a bit.) It shows you what you should worry about and what you shouldn’t. The intersection of the circles is the locus of worry. And it has helped a bit.

h/t: Alexis

Readers’ wildlife photos

March 23, 2021 • 8:00 am

Please send in your photos. I will probably put this feature on hold while I’m in Texas, but, except when I’m gone, the tank is always emptying.

Today’s photos come from regular Tony Eales, an anthropologist in Queensland who loves natural history. Tony’s captions and IDs are indented, and you can enlarge his photos by clicking on them.

Tropical North Queensland part II (part I is here)

Here are a few of the other wonderful organisms I encountered on my brief trip up north to the jungles.
Australian Prismatic Slug (Atopos cf australis). I’m pretty sure there are several species of this slug around, but they all seem to be labelled A. australis. They are predatory slusg with curved teeth in the radula, and they spit acid onto snail shells to help rasp through to the snail inside.
The tracks at Speewah Conservation Park were empty of other humans, which was great for spotting wildlife. I got to approach this Northern Tree Snake (Dendrelaphis calligaster) quite closely without alarming it too much. It’s a slightly built rear-fanged colubrid and presents no danger to humans.
These beautiful Tropical Rockmasters (Diphlebia euphoeoides), a type of flat-wing damselfly, were common around Cairns and the surrounding area. I wish we had such beauties near me. This photo shows a male and female at Lake Eacham.

This is a lichen-mimicking caterpillar, Enispa prolectus. These caterpillars fasten small pieces of lichen to their backs with silk as a form of camouflage.

As the area is a tropical rainforest and it was actually raining while I was there, I was inevitably attacked by many, many leeches. However, I spotted this one (Haemadipsa sp.) on a railing at night actively questing, and I was struck by the bright colours. I have to wonder, are these colours signals to each other, warning, camouflage or just random?

One for Mark Sturtevant: a Pisuarid spider, related to the Dolomedes triton that he featured recently. This one is Hygropoda lineata. These were very common in the north. Rather than living by the water, these spiders make a simple web platform across the surface of broad leaves and sit on top of it, often looking like they are hovering in thin air.
Nephila pilipes, the Giant Golden Orbweaver. These are well named. We have Golden Orbweavers at home, which are big spiders, but these northern ones are mind bending. This one had a body length of about 50mm and was eating a cicada the size of my thumb. The span of the web was about 6 metres from attachment to attachment and the main orb about a metre and a half across.
They are only weakly venomous to humans and very reluctant to bite even when handled, preferring just to climb away.
There were a huge variety of amazing ant species to be found in the forests, but by far the most common were the Green Weaver Ants, Oecophylla smaragdina. I was always checking their trails for signs of the spiders that mimic them. Unfortunately, I didn’t find any. I did however observe their interesting behaviour of holding leaves together like living stitches. Inside the ball of leaves larvae are being hatched. The larvae are then taken by workers and produce silk to tie the leaves together more permanently.
In Speewah Conservation Park there were lots of climbing palms, Calamus caryotoides. The mature stems are festooned with black spines to ward off herbivores. However, these caterpillars, which I’ve yet to ID, use the spines to create a protective home as the crawl around and eat the leaves.
These long-jawed orbweavers, Tetragnatha rubriventris, were very common around Cairns. They have massive hinged chelicerae and the males have large clubbed pedipalps with complicated spiralled spines for placing a sperm packet into the female epigynum. all this weirdness makes them great photo subjects for a really alien look.
Also in Speewah Conservation Park I found this amazing fruiting bodies of the slime mould Tubifera microsperma.
And back at my motel there was a large Peacock Carpenter Bee (Xylocopa (Lestis) sp.) in the flowers of a Monkey Rope vine (Parsonsia sp).