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03 Apr 00:18

Of Slimes and Slimariums

by lonelley

contributed by Crystal Davidson

Sneakily slithering, seeking sustenance, single celled slime molds slowly slide through the forest…

It takes a keen eye, and a good amount of moisture to catch a myxomycete! These tiny friends of fungi are often found on dead wood, but can sometimes even be seen creeping across your lawn.

The first myxo that ever caught my attention was Arcyria denudata, which I first saw in a field guide. I immediately loved the common name “Cotton Candy Slime Mold”. Getting to meet one in real life, however, was even more thrilling, as the tiny pinkish red fruit bodies really do evoke memories of the fluffy fair food! One of the most prolific slimes in our area is Fuligo septica, which has the stomach-churning common name of ‘dog vomit slime mold’. Since I’m not a dog owner, I can’t speculate as to the visual accuracy of this name, but I’d guess it exists for a reason. You’ll often find it creeping through a flower bed in urban areas, though it can be found in the wild as well.

There are also many species of Trichia, Hemitrichia, and Metatrichia that frequent Ohio. Careful examination of the subtle features of the fruiting bodies can sometimes aid in distinguishing them. For instance, this specimen is most likely Hemitrichia clavata, which looks very similar to, but has a more elongated cup at the base than H. calyculata.

Hemitrichia clavata

Another common myxomycete is Physarum polycephalum. “Polycephalum” means “many headed”, and the fruiting stage makes it clear from whence this name came. In the plasmodial stage, P. polycephalum can be difficult to distinguish from Badhamia utricularis and other myxos, but most slimes can’t be identified solely from this stage. Once they fruit, however, the differences are obvious. P. polycephalum usually fruits upwards, away from gravitational forces, whereas B. utricularis typically hangs down.

A fun thing to do with myxomycetes is to capture them and bring them home to start your very own personal slimarium! To create one, you’ll need an enclosed container to keep in both your slime and any unexpected visitors that may sneak home with you. An old fish tank with a bit of plastic wrap over the top worked quite well for me, although any clear enclosure will suffice. I added some large rocks, well decayed pieces of log, a few handfuls of live moss, a bit of water at the bottom, and I periodically misted inside to maintain humidity. When you’ve found a specimen, simply remove a small bit of the substrate along with the myxomycete, and carefully transport it back to the tank. In a pinch, you can even use a clear plastic food container with a moist paper towel at the bottom as a living area.

While slime molds love oats, and they are a consistently consumed food source, I’ve found it to be more interesting to offer them a variety of foods and see what they prefer! They typically love mushrooms, though they have strong preferences on which they will eat. Pleurotus spp. are always a favorite, Postia sp. was not a big hit, they only eat the bacteria off the surface of the Trametes versicolor, and they absolutely abhor Rhodotus palmatus. Additionally, they will eat pasta and the bacteria on the outside of acorns, but despise raspberries and broccoli. This is an example of how slime molds navigate to make choices and select food source.

If you’re wondering how this blob-like organism moves, it does so through a pulsing locomotion. The slime forms “veins” which are wrapped in proteins that squeeze, creating a wave like effect. The waves move forward and recede slightly less with each pulse through the finger-line extensions known as pseudopods. You can see the progress over time here, as well as the ripples of the waves in the second photo.

Since I was eager to find out exactly what my most recent slime pet was, I forced it to fruit by denying it food. Despite the fact that myxomycetes can perceive light and typically avoid it, when they are ready to fruit, they will sometimes climb up to a high point, which may help to increase the range of the spore dispersal. I was quite pleased to discover upon fruiting, that this specimen was in fact Physarum polycephalum, which is often used in lab studies, including the semi-famous study of slime molds solving mazes.

Physarum polycephalum fruiting body

Now you might have thought this story was over at the fruiting, and I did too! Imagine my surprise when after a few months of not introducing anything new into the slimarium, a second slime suddenly appeared! Remember, they are sneaky! In the plasmodial stage, this Arcyria cinerea doesn’t look much different than its roommate, P. polycephalum. Once it fruited, however, the differences were obvious.

Arcyria cinerea fruiting body

It is also interesting to note that there are some fungi that feed off of slime molds. I only discovered this Polycephalomyces tomentosus feeding on this Hemitrichia calyculata once I got home and was editing my photos. Next time, I’ll try to be more observant of the even tinier things.

Polycephalomyces tomentosus feeding on Hemitrichia calyculata

To learn more about these fascinating life forms, consider also joining the Facebook group Slime Mold Identification & Appreciation, which was even mentioned in the recent NOVA special on PBS, “Secret Mind of Slime”.

12 Nov 01:16

(937): look im sitting on my...

(937): look im sitting on my bathroom floor in my underwear snorting cocaine can we talk about this later.
16 Aug 17:01

chrishallbeck: Deep.



22 Mar 23:23

Internet Tolls And The Case For Strong Net Neutrality

by Reed Hastings
The Internet is improving lives everywhere – democratizing access to ideas, services and goods. To ensure the Internet remains humanity's most important platform for progress, net neutrality must be defended and strengthened.

The essence of net neutrality is that ISPs such as AT&T and Comcast don't restrict, influence or otherwise meddle with the choices consumers make. The traditional form of net neutrality which was recently overturned by a Verizon lawsuit is important, but insufficient.

This weak net neutrality isn't enough to protect an open, competitive Internet; a stronger form of net neutrality is required. Strong net neutrality additionally prevents ISPs from charging a toll for interconnection to services like Netflix, YouTube, or Skype, or intermediaries such as Cogent, Akamai or Level 3, to deliver the services and data requested by ISP residential subscribers. Instead, they must provide sufficient access to their network without charge.

Some major ISPs, like Cablevision, already practice strong net neutrality and for their broadband subscribers, the quality of Netflix and other streaming services is outstanding. But on other big ISPs, due to a lack of sufficient interconnectivity, Netflix performance has been constrained, subjecting consumers who pay a lot of money for high-speed Internet to high buffering rates, long wait times and poor video quality. A recent Wall Street Journal article chronicled this degradation using our public data.

Once Netflix agrees to pay the ISP interconnection fees, however, sufficient capacity is made available and high quality service for consumers is restored. If this kind of leverage is effective against Netflix, which is pretty large, imagine the plight of smaller services today and in the future. Roughly the same arbitrary tax is demanded from the intermediaries such as Cogent and Level 3, who supply millions of websites with connectivity, leading to a poor consumer experience.

Without strong net neutrality, big ISPs can demand potentially escalating fees for the interconnection required to deliver high quality service. The big ISPs can make these demands -- driving up costs and prices for everyone else -- because of their market position. For any given U.S. household, there is often only one or two choices for getting high-speed Internet* access and that’s unlikely to change. Furthermore, Internet access is often bundled with other services making it challenging to switch ISPs. It is this lack of consumer choice that leads to the need for strong net neutrality.

Netflix believes strong net neutrality is critical, but in the near term we will in cases pay the toll to the powerful ISPs to protect our consumer experience. When we do so, we don’t pay for priority access against competitors, just for interconnection. A few weeks ago, we agreed to pay Comcast and our members are now getting a good experience again. Comcast has been an industry leader in supporting weak net neutrality, and we hope they’ll support strong net neutrality as well.

ISPs sometimes point to data showing that Netflix members account for about 30% of peak residential Internet traffic, so the ISPs want us to share in their costs. But they don't also offer for Netflix or similar services to share in the ISPs revenue, so cost-sharing makes no sense. When an ISP sells a consumer a 10 or 50 megabits-per-second Internet package, the consumer should get that rate, no matter where the data is coming from.

Some ISPs say that Netflix is unilaterally "dumping as much volume" (Verizon CFO) as it wants onto their networks. Netflix isn't "dumping" data; it's satisfying requests made by ISP customers who pay a lot of money for high speed Internet. Netflix doesn't send data unless members request a movie or TV show.

Interestingly, there is one special case where no-fee interconnection is embraced by the big ISPs -- when they are connecting among themselves. They argue this is because roughly the same amount of data comes and goes between their networks. But when we ask them if we too would qualify for no-fee interconnect if we changed our service to upload as much data as we download** -- thus filling their upstream networks and nearly doubling our total traffic -- there is an uncomfortable silence. That's because the ISP argument isn't sensible. Big ISPs aren't paying money to services like online backup that generate more upstream than downstream traffic. Data direction, in other words, has nothing to do with costs.

ISPs around the world are investing in high-speed Internet and most already practice strong net neutrality. With strong net neutrality, new services requiring high-speed Internet can emerge and become popular, spurring even more demand for the lucrative high-speed packages ISPs offer. With strong net neutrality, everyone avoids the kind of brinkmanship over blackouts that plague the cable industry and harms consumers. As the Wall Street Journal chart shows, we're already getting to the brownout stage. Consumers deserve better.

Some big ISPs are extracting a toll because they can -- they effectively control access to millions of consumers and are willing to sacrifice the interests of their own customers to press Netflix and others to pay. Though they have the scale and power to do this, they should realize it is in their long term interest to back strong net neutrality. While in the short term Netflix will in cases reluctantly pay large ISPs to ensure a high quality member experience, we will continue to fight for the Internet the world needs and deserves.


*Defined as 10 Mbits/sec -- sufficient for a good Skype video, an live game or high quality Netflix streaming. DSL and mobile do not generally offer these speeds.
**in other words, moving to peer-to-peer content delivery