commensal

Most dogs throughout history and even today are not breed dogs in any sense, but are free-breeding human commensals. The population history of these village dogs is potentially much richer than that of modern breeds, which largely reflect genetic variation present in a few dogs in Europe several centuries ago. Village dogs have a nearly global distribution, with most continental populations first established millennia ago. Notably, these village dogs reflect the ancestral stock for all dog breeds, and may represent an important genetic resource for reinvigorating some purebred lineages using some outbred individuals related to the breed founders.

Like many modern breeds, some populations of village dogs are also genetic mixtures of several modern European breed dogs that were relatively recently imported to those areas (e.g. Puerto Rican and central Namibian village dogs). These dogs resumed a scavenging, free-breeding existence (they are ‘secondarily free-breeding’), but they retain little or no localizable genetic signature and do not contain unique genes resulting from local adaptation over millennia.

Other village dog populations, however, have much more ancient roots and are likely to be very informative for deciphering the origin of dogs and the movement of early dog populations across the globe (e.g. Ugandan village dogs). These indigenous village dogs also represent unique genetic resources for understanding local adaptation, and may provide unique services to the humans that live with them.

— 

Ryan Boyko and Adam Boyko, Free-Ranging Dogs and Wildlife Conservation (2014) p. 189

2

Dr Warhol’s Periodic Table of Microbes, The Small Guide to Small Things

85.  At.  Atopobium

You might be inclined to remember that Atopobium (the genus) includes the species Atopobium vaginae, which cause bacterial vaginosis. The organism could be considered a common commensal in most women, but it has been found in about 80% cases of bacterial vaginosis. The relapse rate is about 30%, so appropriate antimicrobial therapy is important.

But for sure you will definitely remember that Atopobium deltae causes a rapidly progressive gangrene of the penis and scrotum known as Fournier gangrene, which is described as a necrotizing fasciitis of the perineal, perianal, or genital region. The condition was first described by Jean Fournier back in 1883 (not to be confused with Joseph Fourier [circa the French Revolution], the mathematician, physicist, and discoverer of the greenhouse effect). At the time, potential causes of Fournier gangrene included: placing a ring around the phallus, ligation of the foreskin for any number of reasons, placing beans or other foreign bodies in the urethra, and excessive intercourse if you’re diabetic or alcoholic.

Atopobium is one of those organisms that have gone through a series of re-naming thanks to contemporary genetic research. The type species is Atopobium minutum, and has been referred to as Bacteroides minutum, Eubacterium minutum, and Lactobacillus minutum.

Atopobium vaginae cells are Gram positive rod-shaped (elliptical cocci or coccobacillus) microbes that measures around 0.6 to 0.9 microns that occur singly, in pairs, or short chains.

Copyright 2017 Warhol

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anonymous asked:

I've been thinking for a long time that he could release and promote a single before dunkirk promo commenses, which could then lead into album promo, that would mean he could just keep building on all of the exposure he would get. I think he's been so smart since the start in how things have progressed and been managed and I am super excited to see how everything ends up coming together. He's going to be so brilliant 🌠

no matter what order he chooses to do things in i know it’s gonna be so so good ✨✨✨✨

3 Main Types of Symbiosis

Mutualism: Mutualism is one of nature’s best examples of teamwork. In a mutualistic symbiosis, both parties get something out of the deal and are better equipped for survival because of their arrangement. Take for instance the live sharksucker (Echeneis naucrates), a species of fish that attaches itself to sharks, whales, and other marine animals and keeps them clean by eating smaller parasites. In exchange for its hygienic help, the sharksucker is protected from predators wary of getting too close to its larger hosts.

Commensalism: In commensalism, one species benefits while the other isn’t harmed. In fact, commensal symbiotes can often be overlooked by their hosts. Take for example, Demodex folliculorum, a tiny species of mite found on almost all human faces. These microscopic creatures live out their three-week or so lifespans in your pores and hair follicles. There’s not a lot to recommend them, exactly, but they also don’t bother anyone except in extreme cases, where they can contribute to skin problems.

Parasitism: Parasites live off of a host, causing irritation and distress while contributing nothing in return. Blood feeders like the common bedbug (Cimex lectularius) are some of the most easily recognized parasites, but blood is far from the only way they parasites take from their hosts. While it’s not noble, parasitism is an effective way of making a living, so much so that nearly every animal species is the host to at least one kind of parasite. Even parasites themselves host free riders, like the bacterium Wolbachia, which lives in bedbugs, though new research suggests it may play a more complicated symbiotic role than once thought.

See symbiosis in action in the newest episode of Shelf Life

Igbo mask dancers performing during the Onwa Asaa festival, Ugwuoba village

The appearance of the moon governs the communal activities such as the commencement of farm work, festivities and ritual offerings. For example, the seventh moon (Onwa asaa) appears in August and marks the month of the thanksgiving service to the ancestors. The community in turn obtains permission to eat new yams without fear of reprisals from their ancestors. The eighth month is Onwa asato, which appears during the month of September or October. Onwa asaa refers to the month when the ritual feast of new yam is celebrated. The seventh month thus becomes the official title by which the activity is known. During this festival, the appearance of masks and the masquerading features merely mark the celebration of the feast.

— Osmund A. C Anigbo (1987). Commensality and Human Relationship Among the Igbo. University of Nigeria Press. Photo: Eliot Elisofon, 1959.

Symbiosis Explainer

In the latest episode of the web series Shelf Life, we learned about the surprising symbiotic relationship between spotted salamanders and algae.
Symbiotic relationships are common in nature, and can take on a wide variety of different forms. While this relationship can play out in many surprising ways, there are three main types of symbiosis seen in nature. Here’s how to tell them apart.

Mutualism: Mutualism is one of nature’s best examples of teamwork. In a mutualistic symbiosis, both parties get something out of the deal and are better equipped for survival because of their arrangement. Take for instance the live sharksucker (Echeneis naucrates), a species of fish that attaches itself to sharks, whales, and other marine animals and keeps them clean by eating smaller parasites. In exchange for its hygienic help, the sharksucker is protected from predators wary of getting too close to its larger hosts.

Commensalism: In commensalism, one species benefits while the other isn’t harmed. In fact, commensal symbiotes can often be overlooked by their hosts. Take for example, Demodex folliculorum, a tiny species of mite found on almost all human faces. These microscopic creatures live out their three-week or so lifespans in your pores and hair follicles. There’s not a lot to recommend them, exactly, but they also don’t bother anyone except in extreme cases, where they can contribute to skin problems. To learn more about the microscopic creatures living in and on your body, visit the special exhibition The Secret World Inside You.

Parasitism: Parasites live off of a host, causing irritation and distress while contributing nothing in return. Blood feeders like the common bedbug (Cimex lectularius) are some of the most easily recognized parasites, but blood is far from the only way they parasites take from their hosts. While it’s not noble, parasitism is an effective way of making a living, so much so that nearly every animal species is the host to at least one kind of parasite. Even parasites themselves host free riders, like the bacterium Wolbachia, which lives in bedbugs, though new research suggests it may play a more complicated symbiotic role than once thought.

Watch the new episode of Shelf Life to see symbiosis in action. 

Phil Lester Appreciation Day 2016

It is nearly that time of the year again where we dedicated a whole day to our favourite youtuber and smol angel bean, Philip Michael Lester.

On August 7 2016 at 00.00 UK time will be the commensement of PLAD. For 24hrs you can submit text posts, fan art, fan fics, fan edits, pictures, gifs, favourite videos, favourite quotes, favourite memories.

You can also, as well as post here, post to twitter with the same hashtag #philappreciationday16

Make sure the above hashtag is the first tag in post you make, as I will be searching through that tag, and reblogging any of your posts.

I hope to see lots of you joining in! In the mean time, can I ask all of you to reblog this post and spread awareness in preparation for the day! Thank you so much 💜

“Sea Potato” (Echinocardium cordatum)

…a species of Loveniid sea urchin which boasts a mostly cosmopolitan distribution. Where it occurs in temperate seas in the north Atlantic, west Pacific, around Australia and New Zealand, as well as South Africa. Sea potatoes are often seen on sandy sea beds, where they will bury themselves constructing small burrows which are lined by mucus secretions. Detritus and other nutrients will collect on these secretions, and made their way to the central area of the burrow, where the sea potato will feed on them. Sea potato burrows are known to house a wide range of commensals, especially the bivalve Tellimya ferruginosa.

Classification

Animalia-Echinodermata-Echinoidea-Spatangoida-Loveniidae-Echinocardium-E. cordatum

Image: Hans Hillewaert