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Saturday, May 28, 2011

Mermaid Jumps Shark

The trailer is out for a film called "Great White Shark: Beyond the Cage of Fear."

There's nothing wrong with a cast of Chippendale's divers (and one "mermaid") trying to "destroy the myth of a mindless killing machine," mind you. But I can't stop laughing over the filmmaker's zany and misguided conceit: dressing a grown woman as a fish (OK, half-fish) so she can briefly get into the frame with a Great White and thus prove that "a shark knows the difference between Us and Dinner." But this picture doesn't tell a thousand words. In fact, it's just too unintentionally ridiculous for words.

Talk about "jumping the shark."

If the 3-meter Great White in that shot turns on that Daryl Hannah look-alike, does it disprove the hypothesis? Then again, how could it, because SHE'S DRESSED AS A FISH!? And if it doesn't, does that confirm the hypothesis -- or simply prove that sharks prefer beefcakes to blondes?

Not So Anomalous After All

It turns out that a hefty Cambrian predator that looked a bit like a cross between a sting ray and a prawn was bigger and hardier than anyone realized. It was widely thought that the anomalocaridids had been successfully displaced by the nautiloids around 510 million years ago. Not true, it now seems.

Dinosaur-tie-donning Yale paleontologist and taphonomist Derek Briggs, who along with colleague Peter Van Roy authored the new report on the basis of fossils found in Morocco, says anomalocaridid had already "become a kind of icon of the 'Cambrian explosion' because it's the largest predator amongst those animals that appeared when all the major groups of Metazoans first appear on the fossil record." But it was also poorly understood for a long time. He notes in this brief film that various parts of the anomalocaridid were initially thought to be separate animals -- the dual barbed appendages in front of the mouth, and the mouth/jaw that looks like the shuttered aperture of a camera. We knew a lot more about them before the Morocco discovery, including that they were probably ravenous predators of soft-bodied organisms like worms and such.

Briggs says the Moroccan revelation is twofold: a) these anomalocarodids were "enormous" at well over 1 meter long; and b) they demonstrate that anomalocaridid or its relatives "persisted" well beyond when the rock record previously suggested, so at least 30 million years beyond the middle Cambrian around 510 million years ago.

"Nature" explains more about these "super-predators" and the Moroccan revelation with regard to their continued survival:
[A]nomalocaridids came in diverse shapes and sizes — from Hurdia victoria, with its triangular carapace, to Schinderhannes bartelsi, with its long, pointed tail — and lived in the areas that are now Europe, the United States, Australia and China. But ancient relatives of sea scorpions and nautiluses that emerged in the Ordovician Period (490 million–440 million years ago) were suspected to have out-competed the anomalocaridids, causing them to die out, says Van Roy.

In 2008, however, an amateur collector, Mohammed Ben Said Ben Moula, discovered specimens that looked like anomalocaridids, Van Roy says. But it wasn't until 2009, when the researchers took a trip to the Fezouata rock formation in southeast Morocco, that they realized just what Ben Moula had discovered.
"National Geographic" has more about their size and evolutionary milieu:
Previous anomalocaridid fossils had shown the animals grew to perhaps 2 feet (0.6 meter) long, which already would have made them the largest animals of the Cambrian period (542 to 501 million years ago)—an evolutionarily explosive time, when invertebrate life evolved into many new varieties, such as sea lilies and worms.

But at a foot longer than previous specimens, the largest of the new anomalocaridids suggests the segmented animals grew to bigger sizes than scientists had imagined.
So while its evolutionary line eventually died out, anomalocaridid was thriving for a lot longer than anyone was giving it credit for.

Monday, May 16, 2011

Ground Control To Major Bobtail

On its historic final journey, the space shuttle "Endeavour" has taken a freckled little Bobtail Squid (Euprymna scolopes) where no squid has gone before. (Photo by Nick Hobgood from Wikipedia Commons)

The idea is to study the response to life in space by a bacteria that part of the squid's natural payload. Will it go all "Deep Blue Sea" on experimenters, like Salmonella did, or at least get altered, like E. coli did?

"New Scientist" explains:
...Jamie Foster of the University of Florida in Gainesville, who is running the experiment, puts it: "Do good bacteria go bad?"

Foster has arranged to send up the bobtail squid Euprymna scolopes, a Pacific species that carries a cargo of bacteria called Vibrio fischeri in its body. The microbes colonise young squid soon after the squid hatch and set up home in their light organs. The squid use the bacteria to generate light, which they shine downwards to ensure they don't cast a visible shadow.
Unbeknownst to the cephalonaut, it's being asked to make the ultimate sacrifice for science:
Foster's experiment is simple. Newly hatched squid that have not yet encountered their bacterial partners will go up to orbit in tubes of seawater. 14 hours after launch, an astronaut will add the bacteria and give them 28 hours to colonise the squid. Then the squid will be killed and fixed solid, and brought back to Earth for examination.
It's just the latest way in which cephalopods are helping unravel the mysteries of life, a topic to which I'll surely return in a future post.

Video: Ice Diver Inspires

"National Geographic" photographer and polar-ice enthusiast Paul Nicklen, who has shared his wild story of an encounter with a seemingly nurturing Leopard Seal in the past, talks more about his passionate love for the Arctic and its inhabitants, as well as polar ice's crucial part in the web of life.

He's an engaging host with an invaluable message in this recent TED talk.