Cone snail venom contains insulin

Screen Shot 2015-01-22 at 13.21.19Photograph by Design Pics Inc.

The geographic cone snail, Conus geographus, is the most venous cone snail, and one of the most venomous animals on the planet; human fatality rates are as high as 65%, from doses of 0.038-0.029 mg/kg.

While some cone snails feed rapidly by impaling prey with harpoon-like teeth that deploy this venom, others feed by extension of a distended ‘false mouth’ acting as a feeding net. This is a slow process, limited in its effectiveness as prey fish must be unaware of the cone snail’s presence, or chemically sedated, to ensure their capture.

Discovery of specialised insulins in the venom complexes of Conus geographus and its congener Conus tulipa, in a study published by Safavi-Hemami et al. in The Proceedings of the National Academy of Sciences on January 20th, is thought to supply such sedation. When injected into fish, the venom and insulin together elicit hypoglycemic shock, a condition characterised by dangerously low blood glucose, which immoblise the fish and allow it to be captured more easily. The fish appear almost passed out, or drunk.

This reaction mixture has been named the ‘nirvana cabal’, and it is thought that the release of the combination of these toxin venoms into the water column could allow entire schools of fish to be simultaneously captured with little effort.

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Electric eels manipulate prey muscle when hunting

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Published in Science on Friday 5th December, a new study has observed interesting behaviours in electric eel predation.

‘Electric eels’ (Electrophorous electricus – some awesome alliteration there) though not actually technically eels, are one of a few groups of marine organisms which harness electric discharges for prey capture and predator deterrence, though many lineages are able to sense these fields. Elasmobranchs of all genera detect electric fields using ampullae of Lorenzini, which are distributed in pores laterally along the fish’s body and predominantly around the head; the movement of prey item’s muscle in the water column generates electric fields which are detected to a very small threshold of sensitivity. Further, a number of Batoid elasmobranchs – the rays – have adapted to produce electricity proportional to their size, up to around 200volts. While the Pacific electric ray uses electricity to stun prey, the less electric ray uses theirs exclusively in predator defence. Elephantnose fish are a group of Osteoglossiformes, the group which contain giant arapaima, and are classified as producing either ‘waves’ and ‘pulses’ to sense their environment.

And finally, one of my favourite animals; the duck-billed platypus (Ornithorhynchus anatinus), uses electroreceptors embedded in the rostrocaudal rows of skin of the bill to determine the size and direction of prey in the water, in conjunction with touch and pressure sensitive mechanoreceptors. These are homologous to the electrosensors in the bills of the related terrestrial Echidna, who have significantly less (≤2000 vs 40,000). Both of these species are Monotremes, and in addition to being the only egg laying mammals, are the only mammals with these electrosensory capabilities.

Electric eels use electrically to ‘illuminate’ their environment, sending out low-voltage pulses and sensing the feedback, much like echolocating bats. However, they are also renowned for their ability to generate extremely high voltage shocks; shocks of up to 600volts, over double that of a UK mains plug.

This has consistently been interpreted as an adaptation to stun and immobilise prey. This makes them easier to eat, and stops otherwise trashing prey from damaging delicate respiratory surfaces around the gill area.

However, this new research by Catania suggests that the discharges eels can generate are specialised. The high frequency, high voltage shocks mentioned above allow immobilisation capture of free swimming prey, or defence against predators. Also known, however, are repeated pairs and triplets of high voltage discharges, which are used when hunting in complex environments.

Catania measured the responses to eels’ electric discharge in the bodies of fish, and found that motor neurone activation is required to produce muscle contraction of the prey fish.

This means that electric eels’ discharges act specifically to activate prey motor neurones, and hence muscle, and that this allows the eels to ‘remotely control’ their desired prey item. They not only immobilise prey, but by repeatedly sending out periodic waves or pulses of electric discharges, that the eel can cause full body involuntary twitching, causing the prey to move and reveal its location – the eel then strikes 10-15 seconds later. These volleys of impluses are advantagous, as an initial twitch and the resulting electrical feedback will inform the eel if the prey item is alive, and worth the energy investment of pursuing it. This also acts to explain why this behaviour is used particularly in cryptic environments, where prey needs to be ‘flushed out’.

With this insight, there is further evidence to support suggestion that organisms that are highly sensitive to and which produce electric fields may use them for additional reasons, including those not exclusively relating to predator-prey interactions, such as sociosexual selection and communicating with conspecifics.

Stephen Hawking would love to play a Bond villian

World-famous physicist and author Professor Stephen Hawking told interviewers at Wired that he would love to play a Bond villian.

My idea role would be a baddie in a James Bond film. I think the wheelchair and the computer voice would fit the part.”

Think about that. Just take a minute and think about how fantastic that would be.

…Done? Alright. Good.

Moving on. Professor Hawking, 72, is often on our screens. He has been played by others is dramatisations of his life; notably, Benedict Cumberbatch in the BBC television film Hawking, and Eddie Redmayne in the widely praised The Theory of Everything, which documented his relationship with his first wife Jane Wilde Hawking, his success in physics, and his diagnosis with and development of motor neurone disease.

However, Hawking has played himself alongside other famous scientists in an episode of Star Trek TNG and The Big Bang Theory, appeared in Monty Python singing the ‘Galaxy Song’, and has featured in episodes of the Simpsons and Futurama, in addition to producing a large number of documentaries about his lifetime of groundbreaking work in the fields of theoretically physics and cosmology.

His being a Bond villain would be both wonderful representation, and mind-bogglingly cool besides – Hawking has dedicated much of his life to increasing the accessibility of, and attempting to increase public interest in, the sciences. In the interview, Hawking spoke about his love of communicating with the world, and his ‘trademark’ American accented synthesised voice.

I enjoy communicating science. It is important that the public understands basic science, if they are not to leave vital decisions to others.”

The full interview will be available in the January issue of Wired, to be published this week, however this interview came about just hours before it was announced that the title and cast of the upcoming 24th James Bond film will be announced this Thursday (4th December) in a live event. I wrote the announcement of this announcement up earlier today for The Edge. I love James Bond. I am pretty much the designated Bond Corespondent. I’ll be in charge of writing up the article after the livestream, as well, even though I’m in a doctor’s appointment to find out if I’m diabetic at the time.

The nurse will be telling me potentially permenantly lifechanging information about my health and I’ll just be like, “Hold up. Daniel is speaking”.

‘Peer reviewed’ journal accepts article exclusively reading “Get Me Off Your Fucking Mailing List”

Image Credit David Mazieres & Eddie Kohler.

When writing a paper, we are told to always aim to both emulate the style of, and reference preferentially from, thoroughly checked, prestigious, and high impact factor journals. It sets you up – if you believe your findings are of a high standard, it sets a precedent they actually are. For a biologist, and many other fields besides, these journals are chiefly Nature and Science. That said, when needing a very particular or obscure reference, my friends and I have been know to spare a giggle at the incredibly niche titles of some journals. The Journal of Vibration and Control, anyone?

This journal in particular came to light a few years ago for an illicit ‘peer review ring’. For anyone unfamiliar with the concept, peer reviewing has been likened to a jury – other academics both within and outside a field critique a paper and its findings, and by consequence decide on its suitability to be considered valid and put forward in primary literature. This ring, then, was essentially a group of academics either outright lying and making up fake aliases, or agreeing to a ‘you scratch my back, I’ll scratch yours’ kind of set up; all of this bypasses the quality control of a journal, gets your findings published faster, and completely compromises the idea that peer reviewed literature is a sign of quality.

This concept was further dragged through the dirt, when this weekend a paper almost exclusively featuring the words “Get Me Off Your Fucking Mailing List” was accepted to the apparently peer reviewed International Journal of Advanced Computer Technology

Hoping to encourage the rather belligerent online journal to leave his inbox alone, Dr. Peter Vamplew of Federation University Australia submitted the article, which was first written by David Mazieres and Eddie Kohler for a similar purpose in 2005. It wasn’t even Vamplew’s own work! But didn’t you know, an independent reviewer apparently found the paper enlightening and “excellent”.

Maybe it was the high quality supporting figures.

Stuff like this is important for visual learners, you know. Image Credit David Mazieres & Eddie Kohler.

The sting in the tail of this story is that excellent or not, the clearly thoroughly vetted International Journal of Advanced Computer Technology was willing to publish this story for the eminently affordable price of $150. Journals such as this speak to the desperation of academics to keep publishing; this is particularly true of new, baby scientists like my colleagues and I hope to be in a couple of years, who will be desperately trying to build up bibliographies to be proud of.

Further, it’s just the simple spread of misinformation. Inadequate science can infiltrate further study and possibly compromise the findings of multiple studies within a field. Plus, information that’s just plain, dangerously wrong can often gain publicity and either

a) never go away, despite the best efforts of the scientific community and popular media – I’m thinking the MMR vaccine and autism controversy, here

b) further smear the good name of science, in a public consciousness were scientists are often though of in the abstract; still pictured exclusively as strange, white lab wearers who never go outside.

It’s the responsibility of any scientist to report the truth, and something saying you haven’t found anything is an entirely valid conclusion. But fake journals willing to publish anything, unread, for a bit of money in hand give academia as a whole a bad name.