Archive for September, 2014

Teeth bigger than its stomach…

Posted: September 27, 2014 in Fish

As we have previously established on this blog, the deep sea is full of horrors, even more so than the rest of Nature. Mainly, this is because of the conditions down there. Light is scarce, so animals have to have huge eyes, to make the most of whatever light there is down there. And whilst sometimes, large eyes can be cute (see Fig. A.) , they can also serve to be incredibly creepy (see Fig. B).

Fig. A. Don’t worry, this is probably the only time you’ll ever see this picture on this blog.

 

 

Fig B. Hatchetfish (Argyropelecus aculeatus). Image from anotheca.com.

Many animals in the deep sea are either black or red, which are generally not colours associated with happy, helpful and harmless beasts (see Fig. C.).

Fig. C. – Black widow (Ladrodectus hesperus). Admittedly, it isn’t from the deep sea, but it shows the point, and you can never have too many pictures of spiders. Image from Wikimedia Commons.

This is because most red light is absorbed by the water by the time one reaches the aptly and needlessly ominously named ‘Twilight Zone’; so any animal which is black or red, as well as proclaiming its allegiance to anarcho-syndicalism, is also pretty much invisible to predators. Finally, because food is (generally) so rare in the depths, predators have to be prepared to be able to eat almost anything; no matter how big it is – so most predators have large, gaping mouths that are best described as ‘maws’ and elastic stomachs (see Fig. D. ). What makes these animals extra-strange is their sheer weirdness, as well (see Fig. E. ).

 

Fig D. Angler fish (species not given). Image from allthatisinteresting.com

Fig. E – the Goblin Shark, Mitsukurina owstoni (Image from Lmaoguys.com)

So alien are these animals that many of them die as they are brought to the surface, much as an unprotected human would very swiftly die if they were sat down on the ocean floor with nothing but Scuba gear. As the pressures in the deep sea are so strong, the animals down there have adapted physiologically – and even at the molecular level, their cell membranes are more fluid than an animal living ‘higher’ up, as the enormous pressures alter the biochemical interactions within the animal. As they’re brought to the surface, however, they die – or at least become very sick – as their swim bladders (or other air filled cavities) expand, and the biochemistry within the animal changes.
After showing you enough Figs to serve up a pretty decent starter*, you may be wondering why we’ve decided to feature Anoplogaster cornuta as a Horrific Animal of the World

*We apologise for that pun; and promise that the intern responsible will undergo a thorough disciplinary procedure.

After all, in common with many deep-sea fish, and proving that Nature is not entirely without mercy, it is rather small, obtaining a maximum length of 18 cm; and its close cousin, A. brachycera, reaches barely a third of that. This is actually fairly common in the deep sea – it saves on resources.

Indeed, the real reason why we featured this fish is simply because of its name.

Fangtooth.
And its easy to see why it got that name. Look at the name. Look at the picture below. Look at the name again. Look at the picture.

Stop looking if you feel dizzy. (Image from monterybayaquarium.org)

Isn’t that name just, somehow, entirely appropriate? The most obvious thing about that fish is its fangs. It doesn’t even matter about the rest of the fish. The first thing you notice about it is the fangs. Admittedly, ‘fangtooth’ actually makes little sense – since a fang is just a tooth. But, as ever when faced with the nightmares of the abyss, logic seems to twist, and calling a fish basically ‘tooth tooth’ makes perfect sense. These teeth are supposedly the largest teeth (proportional to the animal’s size) of any vertebrate alive on the planet today. They are so large that there are sockets on the upperside of the mouth, to accommodate the teeth when the fish closes its mouth. And, according to David Attenborough, the fish can never completely close their mouths, due to the sheer size of the teeth.

 


Of course, they have these teeth due to the shortage of food in the deep ocean – and they live very, very deep indeed, some specimens being found at 5000 metres deep (although  most are found considerably higher up, at 200-2000 metres down – which is still plenty deep). As food is so rare, the fish needs to be able to capture, kill and eat as many other animals as possible – and larger teeth means it can tackle larger prey.
What is slightly curious about these fish is that their scientific genus name, Anoplogaster, actually refers to the animal’s stomach (Wikipedia says it translates to roughly “Unarmed stomach” from the Greek, whilst Fishbase says it translates to “Up + shielded + stomach”. Either way, its a bold, or perhaps crazy, scientist, who can look at the toothy monstrosity below and think “That reminds me of an unarmed, or possibly up-shielded, stomach”.

“Yes, that definitely looks completely defenceless”. (Image from deepseacreatures.org)

Oh, and remember what we were saying there at the start – about deep sea organisms generally being confined to the deep sea simply because their biology is simply too specialized for the upper waters? That doesn’t exactly apply to the Fangtooth. Indeed, taking a leaf out of the Stephen King school of biology, they emerge from the darkness of the deep sea at night, and hunt in the upper waters (a behaviour called diel migration). When day comes, and the increased light means they would be more vulnerable to predators, they sink back down to the depths again. What’s more, various sources (by which we mean poorly referenced internet sites) appear to imply that they can actually survive in surface aquriaums for many months, even when those aquriums barely mimic their natural habitat. Normally, deep sea organisms die fairly swiftly in captivity, but the fangtooth is robust enough to survive the change.

‘Delicate flower’ in no way describes this fish. (Image from Telegraph.co.uk.)

 

On the plus side, it is very small. So, on your list of ‘things to worry about’, ‘Fangtooth fishes infesting our coastlines’ is probably somewhat below, say, “Terrorism”, “Ebola” and “the Wandering Spider that is definitely in your house right now”, and only slightly above “whether the tinfoil hat I wear to protect my head from government mind control satellites makes me look silly” .

 

Really, the problem is with that collar.

 

 

 

 

 

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Well, it has been a long time, but this blog is now back. You can cease now from rending your garments and howling in anguish at the uncaring heavens, and instead sit down and calmly read about the many, many, many, many horrific abominations nature has inflicted upon us, before returning to rending your garments and howling in anguish at the uncaring heavens.

The abomination this particular blog is focusing on is called Vampyroteuthis infernalis, which literally translates as the ‘Vampire Squid from Hell’, and which is more commonly called the Vampire Squid, for reasons which are actually somewhat obscure. On a side-note, Vampire Squid from Hell is now the name of the Death Metal band I have decided to form just now, purely on the basis of that name. It has also been used as a metaphor for the bank Goldman Sachs, which is ridiculous as Cephalopoda are terrible at banking.

Although they do run most utility companies in the UK.

But it is a pretty good name, isn’t it? If you were out to design a name that summed up a rather diabolical looking critter ‘Vampire Squid from Hell’ has to me near the top of the list (perhaps pipped into third place by ‘Spider-wolves’ and ‘Bloodworm’.) Very few things that come from ‘Hell’ are generally soft or cuddly. Vampires, excepting the last decade or so, are walking, blood drinking corpses. And squid (and related Cephalopoda) are just generally creepy. Perhaps it is the tentacles, or the odd flashes of high intelligence that some species show, or perhaps the explanation is simply that Lord Cthulhu has poisoned our minds with His nightmarish psychic assaults from His tomb beneath the waves.

 

 

 

Most scientists also say He is a major contributor to underwater landslides and decreases in fish stocks (imagecredit: Deviantart, JohnDotegowshi).

So really, it is a shame that this name really doesn’t describe the animal. On the plus side, this name really doesn’t describe the animal. For a start, it isn’t from hell, but instead from seas all over the world. It can usually be found dwelling six hundred to eight hundred metres deep, in what is called the Mesopelagic zone or, if you want to be needlessly ominous, the twilight zone. Although not as extreme an environment as the deeper sea, it is dark enough that photosynthesis cannot occur, and so the food chain is ultimately dependent on the upper waters; with organic debris (often given the deceptively cute nickname of ‘marine snow’) falling down and getting eaten. More specifically, it dwells in the Oxygen Minimum Zone, where the concentration of oxygen in the seawater is at its lowest.

Generally, nothing good lurks in any sort of ‘Zone’. (Photo: National Geographic).

Whilst you might think that oxygen would be lower the deeper you go, this is only partially true. The deep water is generally colder than upper layers, and cold water holds more oxygen . Meanwhile, aerobic (oxygen using) bacteria feed on the marine snow, using up oxygen in the process; but most marine snow is consumed fairly high up. So deeper, colder waters may hold more oxygen than the layers above, because the water is colder and there is less marine snow to be consumed.

Anyway, the Vampire Squid is well adapted to these conditions. Its blood pigments bind oxygen far more effectively than the compounds present in other animals, and it has large gills, to soak up as much oxygen as possible. It also has a generally slow and sedate lifestyle, which reduces oxygen loss. Although it can be agile, this only occurs over short distances, and most of the time it just drifts through the waters.

So, it isn’t from hell. Nor, indeed, is it a vampire; instead, it feeds, uniquely amongst cephlapods, on small dead animals, excrement, and other organic waste, rather than living prey. As its arms are connected by a web of flesh, the vampire squid captures food by dangling long (up to eight times the length of the animal’s football sized body) filaments through the water, to which marine snow sticks. The vampire squid then transfers the food to its ‘web’, where is is covered in mucus, collected into larger and larger amounts, and eventually swallowed, which perhaps is the first time the words ‘vampire’, ‘squid’ and ‘web’ have been used in a sentence which was not immediately followed by screaming. Although this diet may not be that nutritious, it at least means it doesn’t use up that much energy. Indeed, even its predator avoidance tactics are a tad lazy. When threatened by predators, it wraps itself in its web, making it appear larger and covered with spikes. As well as this, bioluminiscent patches on the tips of its arms glow blue, confusing predators. Finally, if ‘turning into a spikey deathball’ and ‘trippy light show’ don’t work, it simply squirts out a cloud of mucus, mixed with bioluminiscent bacteria, and escapes in the confusion.

A vampire squid almost looking cute. (Photo: National Geographic).

A vampire squid looking rather less cute. (Photo: mythsmadereal.blogspot).

Finally, it isn’t actually a squid. It has eight arms, but is not an octopus either, although it is more closely related to them. Instead, it is in a group called the Vampyromorphida which consists entirely of this species and a number of extinct ones.

Again, scientists favour the ‘Cthulhu’ theory.

 

 

In short, the name ‘Vampire Squid from Hell’ scores 0/3 for accuracy, but 100/10 for nightmarish visions. And after all, isn’t promoting a sense of dark horror the main point of taxonomy?

Again, a number of good sources are:

http://www.thecephalopodpage.org/vsfh.php

http://www.thecephalopodpage.org/vampy.php

http://www.newscientist.com/article/dn22299-vampire-squid-from-hell-eats-faeces-to-survive-depths.html#.VAjS7PldU2Y

http://news.nationalgeographic.com/news/2010/01/100203-squid-vampire-threatened-video/

https://www.youtube.com/watch?v=S3CJIKKSUpg