Rogues Gallery: The Great White Shark (center) joins the ranks of infamous serial killers. Clockwise from upper left: Richard Speck, Jeffrey Dahmer, Charles Whitman, John Wayne Gacy, Charlie Manson, Dennis Radar (BTK Killer), Ed Gein (technically not a serial killer but one weird dude), Ted Bundy, David (Son of Sam) Berkowitz, and Henry Lee Lucas.
Courtesy Public Domain image composite by Mark RyanA new study published in the Journal of Zoology likens the predatory behavior of great white sharks to that of human serial killers.
Both the sharks and their human serial-killing counterparts use geographic profiling to hunt their prey. Co-author Neil Hammerschlag, a University of Miami researcher in the Rosenstiel School of Marine and Atmospheric Sciences says the predators “must get close enough to check out prey and figure out their movements, but they also must be far enough way so that they themselves won't be easily tracked. They must use known traveling routes. For human killers, these would be things like subways, buses and freeways. For great whites, these would include channels, reef edges and other topographical features."
In the waters off Seal Island in South Africa's False Bay, the research team (which included a criminal-profiling retired police officer) observed adult sharks launching their attacks from very focused anchor points just like serial killers lurk about familiar territory as they cruise for hapless victims. They found the sharks positioned themselves about 100 yards from the island in 80 feet of water, close enough for attack but far enough away to remain undetected. The depth and distance also allowed the predators to build up enough speed to start the attack.
Whether this behavior applies to all human serial killers, I’m not sure. For example, I don’t know that the Manson family stalked any of their victims, and Richard Hitchcock and Perry Smith (of In Cold Blood notoriety) originally selected the Clutter family in Kansas for robbery purposes, but in general the comparisons are interesting.
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Tags : For those Hawaiian albatrosses who just can't get the hanging of flying, there's always a tiger shark nearby to provide some extra motivation. Just watch the video below. If you want to skip the Mr. Rogers'-like commentary, mute the sound on your computer. I found it much better that way.
Sometimes, there isn't safety in numbers. And most of the time, I think, it's probably a bummer to be a sardine. But it's really tough to be one of these sardines!
More cool video and an explanation of how all that was caught on film here.
A modern blacktip shark: living a modern life on her own.
Courtesy Albert Kok
*The original headline here was "Immaculate conception observed. In a shark." However, it was pointed out to me that "immaculate conception" and "virgin birth" really aren't the same thing. I changed it, but I resent the implication that I don't know the difference. Just because I get things wrong all the time, it doesn't mean that I was wrong about this. Not, you know, necessarily.
It looks like lady sharks have won another battle of the sexes. The sex war had been fought to a standstill, a stalemate siege, if you will, with the male army relying on the “well, you’ll need us eventually” tactic.
Apparently this isn’t necessarily the case. Deep inside the female Fortress of Celibacy, a devious plan was being hatched: virgin birth.
(Many types of sharks, it should be noted, give live birth, like mammals, instead of laying eggs.)
There have, in fact, been two documented cases of ladies-only shark reproduction. The first was in the Omaha Zoo, where a female hammerhead shark unexpectedly gave birth to a baby shark (called a “pup”) in her tank. Unfortunately, some of the other sharks (of a different species) in her tank immediately ate the pup. Whoops. But DNA tests were done on the… leftover chunks of the pup, I guess, and they showed that the baby did not have a father.
The other case happened in May of last year, with the research results being released this last week (hey, sometimes science stays out all night and gets up late, so give it a break). A blacktip shark named Tidbit had been living at the Virginia Aquarium and Marine Science Center for the last eight years, with no contact with males sharks of her species. When Tidbit died mysteriously last May, an autopsy revealed her nearly full-term pregnancy (the stress-related complications of which were probably what did her in). The shark pup had died as well—and aquarium staff believed that it would have been eaten by the tiger sharks in the same tank anyway had it actually been born—but genetic testing revealed it to be Tidbit’s child, and Tidbit’s alone.
Scientists studying the bizarre pregnancies believe that the pups got all the required chromosomes when the mother’s egg split, and then reunited—a process called "parthogenesis.”
Single-sex reproduction, it’s believed, might be an adaptation to situations when there are too few male sharks in a wild population. It’s rare enough, however, that it would be very unlikely that sharks could survive through pathogenesis alone. The process results in a lack of genetic diversity as well, which could leave individuals vulnerable to congenital disorders.
So, ladies, I salute your ingenuity, but you’re not rid of us yet.
Another record holder: Sign touting Paris, Tennessee, as the 'Home of the World's Biggest Fish Fry
Courtesy Photo by Dieter C. Ullrich, for Worlds Biggest Fish Fry, a Tennessee Local Legacies projectLooks like the world of piscine superlatives has a new leader in the Deepest Living Fish category. The highly-pressurized Pseudoliparis amblystomopsis, has been videotaped feeding on shrimp at a depth of 4.8 miles. That’s a lot atmospheres crushing down on it, but it doesn’t seem to mind.
Scientists from the UK and Japan used remote controlled robots with cameras to film the feed-fest in the Japan Trench located around the Pacific Rim. Seventeen of the fish can be seen in the video scurrying about the ocean floor. You can see watch video of the new record holders here.
You notice the category is for Deepest LIVING Fish. The record for deepest of any fish is held by Abyssobrotula galatheae, a fish scooped up from the bottom of the Puerto Rico Trench. Unfortunately, it was dead, so it was competing in an entirely different category.
Well, anyway, both fish join the ranks of other gilled record holders. And while we’re at it, we may as well review them. The title for smallest is held currently by Paedocypris progenetica, a bizarre little creature discovered living in highly acidic waters on the island of Sumatra. It’s about the length of your thumbnail, and also holds the record for smallest vertebrate. On the other hand, the world’s largest fish is the whale shark (Rhincodon typus). If any of you guessed it was the blue whale, you need to turn off your Xbox machines and bask in my pity. By the way, the whale shark can grow up to 40 feet long, so I guess it’s also the world’s longest.
The world’s slowest fish is the seahorse (Hippocampus sp.) which drags along at .001 per hour, and would take about an hour to move five feet. The sailfish, Istiophorus platypterus, which has been clocked at 68 miles per hour, is the fastest. Not bad for giant-finned brute that can weigh up to 200 pounds.
The winner of the World’s Ugliest Fish is as yet undecided, and probably has something to do with the fact there’s not even a category for Most Beautiful Fish. But I think the right choice was made for the Scariest Fish. You wouldn't want to meet him in a dark sewer.
I suppose the record holder of the Funniest Fish title could be the clownfish (Amphiprion ocellaris), but the category seems too broad. Funniest how? Looking? Tasting? Ability to tell a joke? The Dumbest Fish in the World category is equally too broad? Again, it depends on the criteria. It certainly could be the spawning moronic salmon you always see on nature programs jumping right into the waiting jaws of a hungry grizzly bear. Or it could be all fish.
Since I’ve taken it this far, here are some lesser-known categories. I suppose the Fastest Fish Recipe could somehow involve a sailfish, but I doubt the World’s Biggest Fish Fry in Paris, Tennessee has anything to do with the whale shark.
Cow pointing north: Maybe THIS is why you always see animals on weather vanes
Courtesy Leo ReynoldsResearchers in Germany used Google Earth to examine hundreds of aerial images of cattle herds at rest and found that 2 out of 3 cows tended to align their bodies north-south. It seems that no one has really ever noticed this before, which is a little shocking. On the other hand it's nice to know that science still has some basic observations left to be made.
At first I was a bit skeptical. As a kid I'd heard that you could tell if it was going to rain depending on whether cows were laying down or not, which is a silly tale for sure...so maybe this was a similar situation? How would cows sense the Earth's magnetic field anyways? Actually, lots of animals can sense the earth's magnetic field:
- Bacteria - Small strings of magnetite in bacteria, called magnetosomes, have actually been shown to rotate to align with the Earth's magnetic field.
- Birds - One group of researchers found chemicals called cryptochromes in the eyes of some birds. These chemicals change in the presence of a magnetic field and may help the birds see the north-south axis as they fly.
- Sharks - Sharks have receptors in their brains that help them perceive the magnetic field. When sharks swim in tanks they normally swim around the edges, but move randomly when the normal magnetic field is disturbed in some fashion.
Most of this research is still under-way and new discoveries may give us different explanations about how animals sense the Earth's magnetic field. Yet, it is certain that all varieties of creatures, cows included, seem to be able to sense the Earth's weak yet significant magnetic field.
What about you? Can you feel North?
We’ve done our best here on Science Buzz to dispel the myths of sharks gobbling up surfers and other ocean goers. Now here comes this story from New Zealand (doesn’t all the weird stuff seem to happen there?) about one surfer’s really bad day.
Bring 'em on: Come on you nasty sharks...I'll take you all on. (Flickr photo by Cayusa)The Miami Dolphins on the NFL football field maybe struggling through a winless season so far, but their namesakes off the coast of California chalked up a big win a few months ago.
When surfer Todd Endris was surfing near Monterey on Aug. 28, a 12- to 15-foot great white shark attacked him. It’s not uncommon for surfers to be the targets of sharks, who look up through the water to see what they think is a tasty seal.
Three shark bites peeled skin off his back and had ripped his right leg down to the bone. Then to the rescue came a pod of dolphins.
The formed a protective ring around him, allowing Endris to get his wits about him, paddle to shore and get first aid attention on shore from a friend.
I heard Endris share his tale on the Today Show earlier this week. You can get the full report by clicking here. But my biggest question was left unanswered. Why did the dolphins intervene?
Science doesn’t have the answer yet, but cases of dolphins rescuing people go back to tales from ancient Greece.
Just last year, four lifeguards in New Zealand were saved from sharks by the similar action of a pod of dolphins.
One more interesting twist to the story, within six weeks Endris was back on his surfboard riding the waters off on Monterey again.
So what do you think is at play with dolphins coming to the rescue? Do you think they do this for other species as well, or just humans? Share your thoughts here with Science Buzz readers.
A Basking Shark: Just... basking? (image courtesy of Wikimedia Commons)I gots monsters on the brain!
The Loch Ness Monster (or possibly elephant) has been a pretty hot topic around Science Buzz lately, so this article caught my eye.
A Scottish geneticist, Dr. Yvonne Simpson, has been researching the "Orkney Beast” (also known as the Stronsay Beast), and will be comparing it to the Loch Ness Monster in a talk she will be giving at the Highlands Science Festival this week.
The Orkney Beast was this huge, bizarre carcass that washed up on the shore of Stronsay, in the Orkney Islands, in 1808. It was pretty rotten at the time, but everybody seemed to agree that it was some sort of sea serpent (it was 55 feet long, with a 15 foot “neck,” and measured 10 feet around). However, a couple of anatomists later decided that it was probably a shark, specifically a large basking shark. The locals were pretty disappointed with this, but who can argue with an anatomist?
The Orkney/Stronsay Beast: A drawing of the carcass, made in 1808. (image courtesy of Wikimedia Commons)
Even if it was a shark, the Orkney Beast remains an interesting find. The largest basking shark (which is a filter feeder, and the second largest shark after the whale shark) ever recorded was 40 feet, significantly smaller than the beast’s 55 feet.
The skull and “paw” of the creature were sent to London in the 19th century, but were destroyed in World War II. Some remains still exist at Edinburgh’s Royal Museum, however, and Dr. Simpson was given the chance to study them. The article didn’t say what Simpson, who has a PhD in the field of DNA damage repair, made of them.
I don’t know that the geneticist is claiming that Nessie or the Orkney Beast are genuine monsters (what a strange phrase), but she points out that the drawings and descriptions made of the carcass at Orkney are strikingly similar to descriptions in “eyewitness accounts” of Nessie. It’s an interesting coincidence, although I suppose people often see what they want to see, even when looking at giant, rotting fish.
Also, this is kind of interesting. Apparently there’s no shortage of Scottish loch monsters.
A shark, doing it's best: Mostly he just wants to be left alone. (photo by Mshai on flickr.com)Scientists in New South Wales and Florida are testing a new method of measuring the biting force of a great white shark using computer models.
Attempts have been made to measure sharks’ biting force underwater, in captivity and in the wild, although these are known to provide inadequate results. Sharks will generally do weak a “test bite” before applying the full force of their jaws, and these test bites are generally all that’s measured.
In this new experiment, researchers are dissecting a 2.4-meter long great white shark, in part to make an extremely accurate computer model of its anatomy, and in part to drive home the point that the animal should have just allowed them to measure its bite while it was alive. Advanced computing methods, originally developed for “calculating stresses in structures such as bridges,” will then be applied to the model, and should provide a much more accurate range of the shark’s biting force.
This process contrasts sharply with my own, I believe, much more elegant test of shark biting power. There are several simple steps involved in my method: Step 1 – gather a variety of small to medium sized objects. Step 2 - Rate the hardness of these objects, not on an objectively quantified scale, but relatively (for example: The kitten is harder than the pillow, but not as hard as the dictionary). Step 3 - Take these objects to your nearest shark. Get the shark to bite the objects (this can be difficult, but the right combination of chum and verbal abuse should do the trick). You will then have a simple and easy to understand scale of shark biting strength (for example: the shark could crush the pillow, the kitten, the dictionary, and the cookie jar, but not the lawn mower engine). If you still feel, at this point, that you need a measurement that uses more universally accepted units, you can then crush similar objects by yourself, far away from the shark, using free weights, or forty-pound bags of dog food. These can then be easily converted into newtons, or pounds per square inch, or whatever your physics teacher requires.
If the computer model method proves to give reasonably accurate results, I suppose it will then be up to individual researchers to choose that method or mine. It will just depend on whether someone doesn’t want to get their hands dirty, or if they care about style and integrity.
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