Archive for The Realm of Bizzare

Carnivorous snails, so how does that work?

// April 22nd, 2013 // Comments Off on Carnivorous snails, so how does that work? // Recent Research, The Realm of Bizzare

Perrottetia dermapyrrhosa, one of the newly described species from Thailand. Credit: Somsak Panha. License CC BY 3.0

Perrottetia dermapyrrhosa, one of the newly described species from Thailand. Credit: Somsak Panha. License CC BY 3.0

Three new species of brightly coloured carnivorous snail have been found in the limestone hills of Northern Thailand.

Each of the species is only found on one or a handful of hills, some of which have become limestone quarries. Pretty impressive, as a quarry is not a friendly habitat for an animal whose main predator is the boot.

As well as coming in a range of fancy colours, the new species are characterised by nothing less than the shape of their genitals. All from the Perrottetia aquilonaria has a club-shaped penis and penial hooks (sounds painful?), while P. dermapyrrhosa has a long penial sheath, long, scattered penial hooks and vaginal hooks.

It seems like snail penises are a common way to distinguish between species, and there must be quite an art to it. Take this rather lengthy description of P. aquilonaria’s junk.

“Genitalia with a long, slender penis; penial sheath short, about half of penis length; internal wall of introverted penis with black to brown penial hooks; vas deferens passes through a short section of penial sheath before connecting distally to penis; vagina and free oviduct short to long, vaginal hooks may be present; gametolytic duct and sac may not extend as far as albumin gland; seminal vesicle present with about the same length from vesicle to talon.”

If you click through to the complete article, published open-access on peer-reviewed ZooKeys, you can even see some pictures of penial hooks and vaginal corrugated folds. Come on, what else are you going to do with your day?

Perrottetia aquilonaria, another newly described species. Credit: Somsak Panha. CC BY 3.0

Perrottetia aquilonaria, another newly described species. Credit: Somsak Panha. CC BY 3.0

It all sounds rather saucy, and top-notch science research, but I got caught up on this idea of a carnivorous snail. I mean, what IS that? It sounds like something from an old Doctor Who episode, back when the creepy alien du jour was footage of maggots, zoomed in so they looked gigantic. These day’s it’s terrifying ghosts with their mouth all screamy and sideways and it looks like something from The Exorcism of Emily Rose.

They may not be lions and tigers, but carnivorous snails are nonetheless vicious. Some of the species we have in Australia are small and are probably in your garden right now, others are big black ones that live in the Victorian rainforest.

Carnivorous snails hunt other snails, following their slime trail until they catch up with them. Now, most snails have a tongue like a rasp, and they eat lettuce leaves and such by simply licking them away with their tongue-which-works-like-teeth. Carnivorous snails upsize the rasp for big-ass hooks, and when they catch up with their prey they give them a lick and stick their hooks in.

If you’ve ever poked a snail, you know they slip inside their shell and produce gross foam to stop you poking them (no means no). Unfortunately they try the same trick when they get licked by a carnivorous snail, and the attacker has already shoved its hooks in so the snail unwittingly sucks the hunter right into its shell with it. Then the predator just licks away until there’s nothing left.

Actually, that does sound like a creepy Doctor Who episode.

Carnivorous snails also hunt worms, hooking ’em and eating ’em like spaghetti. There’s a great discussion of carnivorous worms on land and sea here on the ABC Radio website.

The research was performed by Chulalongkorn University, Bangkok and the Natural History Museum, London.

ResearchBlogging.orgSiriboon, T., Sutcharit, C., Naggs, F., & Panha, S. (2013). Three new species of the carnivorous snail genus Perrottetia Kobelt, 1905 from Thailand (Pulmonata, Streptaxidae) ZooKeys, 287, 41-57 DOI: 10.3897/zookeys.287.4572

Vampire squid on Occupy Wall Street, biology of Vampyroteuthis infernalis

// December 14th, 2011 // Comments Off on Vampire squid on Occupy Wall Street, biology of Vampyroteuthis infernalis // The Realm of Bizzare

Occupy Wall Street protesters took up arms – eight of them – in their march on Monday. Carrying craftastic models of vampire squid high above their heads, in homage to Matt Taibbi’s description of the bank as “a great vampire squid wrapped around the face of humanity, relentlessly jamming its blood funnel into anything that smells like money” in Rolling Stones, 2008.

Harsh words, right? I mean, vampire squids are totally awesome!

The vampire squid inhabits the cold, high-pressure environment of the deep sea. Light is absorbed by the water, making it perpetually twilight. A vampire in twilight, that’s not horrifying, that’s dreamy, amiright? Don’t hit your head if you swoon.

We don’t know much about these little dudes because they dwell in that most mysterious of spots, the deep sea. Vampyroteuthis infernalis means vampire squid from hell, but it’s not even technically a squid. Or an octopus. It’s got an order all of it’s own.

They have a consistency similar to a jellyfish, quite gelatinous. Like many jellyfish, it swims by shooting out a jet of water behind it to propel it forward, but it has a couple of fins for manouvering. It has eight arms and two extra arms which hide in its ‘pockets’ and can extend the length of its body when needed.

This National Geographic vid is pure pirate gold for high quality images of the creature.

They hold the title for the largest eyes relative to their body. An individual about six inches long has an eye an inch across, about the same as a full-grown dog. All the better to see you with, my dear. They also have a receptacle behind their eye for spermatangia, the tough sac of sperm ejaculated from the specialised arms of a lover. Just imagine date night

The most brilliant behaviour is their bioluminescence. These guys glow!

When startled, squid may shoot out ink to confuse predators. That’s not much good when you live in twilight, so instead the vampire squid shoots out glowing balls that dazzle and confuse. Over a thousand discrete bright particles within a matrix of mucous. Picture that, you’re out looking for a snack late at night, feeling pretty hungry, you think you smell something good and suddenly there’s some wacko waving glowsticks and snot in your face!

Another defensive ploy is to go into pineapple pose. Turning their bell-shaped tentacles over them, they completely change their shape (going kind of inside out). They light up some spots on their head which animals may take for eyes, which glow and then shrink as if the animal has swum away. Even if you didn’t buy that the animal was gone, looking at the videos, you wouldn’t want to eat that.

Stephen Fry gave respect to these sweet deep sea entities in this clip from QI. Hat tip to Dr M at Deep Sea News.

Oh… and about that quote Occupy Wall Street are marching for. The vampire squid’s diet seems to consist of molluscs, fish and crustaceans. As far as we know, it’s not a blood sucker, and Tree of Life. describes the funnel as absent. That must make it hard to stick said metaphorical blood funnel into anything, whether it smells like money or not.

Recommended links

In the QI link, they say the bioluminescence explosion is like John Barrowman! You might know Barrowman as the immortal Captain Jack Harkness from Dr Who and Torchwood, but blow me down, that captain can dance!

Still got time for more videos? Here’s David Attenborough talking about the deep ocean.

The majority of this info was from Tree of Life.

Exploring the blurry line between colony and individual

// August 3rd, 2011 // 1 Comment » // The Realm of Bizzare

I found this great post on the Portuguese man-o-war, known as the bluebottle in Australia, over at Deep Sea News the other day. It’s eating a fish!

The post also said:

Remember this species is colonial and made of four different polyps or zooids, working in unison and dividing labor. The bladder is a single polyp called a pneumatophore. The long tentacles are dactylzooids used for fishing. The dactylzooids bring the fish up to another set of zooids, gastrozooids, responsible for digestion. Last, there is set of zooids, gonozooids, in charge of reproduction.

So it looks like a jellyfish, but it ain’t. It’s a colony of four specialists working together, each with their own nervous system but incapable of living by themselves.

Bluebottle on Woolongong Beach, NSW. Image by Fiona Wilkinson

As I was doing a bit of research about bluebottles and how they sting even when dead and dried up, I came across an interesting question. How do they reproduce? If the gonozooids are responsible for getting jiggy with it, don’t they just make more gonozooids? Where do the rest of the polyps come from?

Well, no one really is a hundred percent sure. I guess that’s fair enough, studying a swarm (a navy) of man-o-wars during mating season doesn’t sound too good. But here’s what they think.

A gonozooid from one man-o-war will make sperm which combines with an egg from another man-o-war gonozooid. Hey presto, you’ve got fertilisation and one embryo – which will become the bladder polyp at the top. That embryo divides several times, then reproduces asexually to make more zooids, which bud out of it. The budding polyps will become either tentacle, digestion or reproduction individuals.

That’s where I got confused. Does this mean that each of the zooids actually come from a single polyp? Are they just differentiated forms of the original polyp, specialised for their particular role? How is this different to a human embryo producing heart cells?

One explanation uses phylogenetics – comparing organisms to see how similar and different they are. Each zooid is similar to solitary Cnidaria (the phylum that includes jellyfish, coral and bluebottles), so can be considered an individual in its own right and a bluebottle as a colony.

But if we define an individual as something with similarity to other individuals, then all the cells of a multicellular organism would be individuals. Are individual humans really colonies of individual human cells? Really, the microbes on and in you outnumber your human cells 10 to one, so you’re more like a walking microbial factory anyway.

White poplars, a kind of aspen, form clonal colonies. Image by Jacob Halun

I think we have a very human-centric model for defining individuals, which is not surprising really. But most species on the planet don’t reproduce like we do, the boundaries between individual and colony are much less clear.

Take aspen trees, which can grow by seeds (sexually) or by underground runners which sprout a tree-clone (asexually.) Over time the runners can decay separating the trees. How can we tell if the trees are individuals or clones, and if we can’t, how do we study adaptation and natural selection?

Tasmania has these Huon pines that are the oldest genetically identical stand of trees which has lasted 10,000 years. Each tree lives about 2,000 years, but the original tree renews itself through genetic clones. Tassie also has the oldest genetically identical plants, clones of King’s lomatia estimated to be at least 43,000 years old.

Strawberries do it too, as do fungus. A single specimen of Armillaria solidepes was found in Oregon the size of 1,220 football pitches and estimated at 2,400 years old. It’s one of the largest organisms in the world.

Where does the individual end and a colony begin? Looking at all the bizarre stuff out there, I can’t help but wonder if we’re the weird ones.

ResearchBlogging.org

Clarke, E. (2010). The Problem of Biological Individuality Biological Theory, 5 (4), 312-325 DOI: 10.1162/BIOT_a_00068

Read it at the homepage of Ellen Clarke

Radioactive decay of teaspoons in the workplace

// January 30th, 2011 // 22 Comments » // Just for Fun, Recent Research, The Realm of Bizzare

missing teaspoonsHave you ever noticed a mysterious loss of teaspoons at your workplace? Maybe it’s not teaspoons, but some other cutlery item. At my old work it was forks, which dwindled even when I bought new replacement ones. At the Australian National University neither spoon nor fork were safe, causing some students to eat salad with two knives as chopsticks.

The same thing was happening at the Burnett Institute in Australia. Teaspoons were critically low, no matter how many new ones bought. Clearly it was time for science.

“Exasperated by our consequent inability to stir in our sugar and to accurately dispense instant coffee, we decided to respond in time honoured epidemiologists’ fashion and measure the phenomenon,” they said in the paper.

They numbered 70 teaspoons and placed them in tearooms around the institute. Lo and behold, they started to disappear. Every week they counted the remaining teaspoons, probably with a lot of suppressed giggling and delight.

After five months, 56 out of 70 teaspoons disappeared, that’s 80%. The half life of the teaspoons was 81 days.

Teaspoons in communal tearooms disappeared faster than those in tearooms specifically for certain projects. Expensive teaspoons disappeared no faster than cheap ones.

According to the study, “at this rate, an estimated 250 teaspoons would need to be purchased annually to maintain a practical institute-wide population of 70 teaspoons.” The cost? About $100. Extrapolate that to the workforce of Melbourne, some 2.4 million people, and you’re looking at quite a wad of cash.

Stapler sugarAnd it’s not just economic loss, it’s also workplace satisfaction. “Teaspoon displacement and loss leads to the use of forks, knives, and staplers to measure out coffee and sugar,” the study suggested. Staplers? You know it’s a bad day in the office when you’re measuring sugar with a stapler. Indeed, nobody in the office said they were “highly satisfied” with the number of teaspoons in a survey they conducted at the end of the study. Yes, they even did a survey.

But why are teaspoons such hot property?

The study gives a few possible theories. Perhaps there are so many teaspoons, people don’t think it will matter if they take one home. Over time the small acts of thievery add up until there are no teaspoons left.

Alternatively, and I can say this no better than the authors, “Somewhere in the cosmos, along with all the planets inhabited by humanoids, reptiloids, walking treeoids, and superintelligent shades of the colour blue, a planet is entirely given over to spoon life-forms. Unattended spoons make their way to this planet, slipping away through space to a world where they enjoy a uniquely spoonoid lifestyle, responding to highly spoon oriented stimuli, and generally leading the spoon equivalent of the good life.”

Their final theory is les choses sont contre nous “things are against us.” “Resistentialism is the belief that inanimate objects have a natural antipathy towards humans, and therefore it is not people who control things but things that increasingly control people,” says the study. Think of all the time you spend cleaning, buying, repairing, using and selling things. Do items really control our lives, sending us on some materialistic goose chase for reasons we cannot yet understand? I can only assume Yes.

I want to hear from anyone who has experienced this phenomenon, be it spoons, forks or knives. What goes missing in your workplace, and why do they constantly disappear. And what is the spoon equivalent of the good life?

ResearchBlogging.orgLim, M. (2005). The case of the disappearing teaspoons: longitudinal cohort study of the displacement of teaspoons in an Australian research institute BMJ, 331 (7531), 1498-1500 DOI: 10.1136/bmj.331.7531.1498

Massive hat tip to James at Disease Prone, who said my posts had slowed down and suggested this paper.

How marsupial embryos develop (a short story)

// December 6th, 2010 // Comments Off on How marsupial embryos develop (a short story) // Recent Research, The Realm of Bizzare

An opossum joey. Image credit Anne Keyte

Marsupials are just plain weird when it comes to procreating.

I’m not talking about bifurcated penises (where the penis has two heads) although that’s pretty freaking weird. I’m talking about the embryos.

When a baby marsupial is born after a 4-5 week gestation, it’s a tiny pink speck of nothing much. About the same size as a jelly bean, it’s hairless, blind, and most of its brain has not developed.

In this state, the joey has to crawl across its mother’s fur and find its way into her pouch. Inside the pouch it continues to develop, growing on the nutrients it sucks from a teat.

It stays there for several months before it emerges, looking more like an animal and less like a little pink alien.

This bizarre method of procreation is the subject of a recent study into developmental biology. The writers, Anne Keyte and Kathleen Smith, found that although a joey is extremely underdeveloped when it is born, some of it features are accelerated. For example it’s forearms grow much faster than the rest of it. The joey has guns! It uses those strong arms to meander through mountains of fur and into the pouch. By comparison, its hindlegs are undeveloped and almost like jelly.

The study used opossum embryos and compared them to mouse embryos of the same age. They used two markers, Tbx4 and Tbx5, to track the development of the fore and hind limbs respectively. Both these genes were switched on earlier than in the mouse, but the forearms were especially beefy. Strangely the hindlimbs do not develop early like the forelimbs, even though the genes are switched on in both.

Not only is gene expression different in marsupials, the forearms were also allocated more red blood cells during development. This gives growing cells the energy they need to become big and strong. The spinal nerves grew into the forelimb buds differently as well.

This research rules out the assumption that limbs arise because of signaling from partially developed organs. The organs in a marsupial are simply not developed enough.

Marsupial faces also develop at an accelerated rate to allow the joey to suckle when it gets to the pouch.

But why such the strange method of procreation. Did marsupials not even THINK to evolve themselves a placenta??? “There are probably 50 explanations for why marsupials develop outside the womb, and none of them are very good,” says Anne.

Keyte, A., & Smith, K. (2010). Developmental origins of precocial forelimbs in marsupial neonates Development, 137 (24), 4283-4294 DOI: 10.1242/dev.049445ResearchBlogging.org






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