“Rebel” Coelacanth
Illustration courtesy Michael Skrepnick
Rebellatrix, a newfound species of coelacanth, chases down Triassic prey in an illustration.
The coelacanth (pronounced SEE-la-kanth) is a primitive, slow-moving fish that’s sometimes called a living fossil, because it apparently existed largely unchanged for 320 million years.
There are 40 known coelacanth species, 2 of which are alive today. All other known coelacanths have broad, rounded tails designed for slow bursts of motion.
But Rebellatrix had a huge, forked tail and streamlined body that likely allowed the ancient fish to cruise long distances and hunt prey at high speeds, said study leader Andrew Wendruff, a biologist at the University of Alberta in Canada.
According to Wendruff, the team named the discovery Rebellatrix because, like a true rebel, “it does everything a coelacanth should not do.”
—Christine Dell’Amore
--- 4 weeks ago --- 16 notes ---Anguilla Bank Skink
Photograph courtesy Karl Questal
The Anguilla bank skink (pictured) is among 24 new species of skink found in the Caribbean—and one of only two known species in the region with a blue tail, according to a new study.
The Caribbean had been thought to house just six species of these smooth-scaled lizards. But when study leader Blair Hedges and colleagues reexamined skink specimens in museums around the world, they found that the animals were much more diverse.
In addition to the 6 known species, the team found 24 brand new species and 9 species that had been previously described—and sometimes photographed—but considered invalid.
In total, the team says, the Caribbean now has 39 known skink species.
“I was completely taken by surprise, because I’ve been working in this area for more than 25 years, and I’ve been to a lot of these islands,” said Hedges, a biologist at Penn State University.
(Also see photos: “‘Glam Rock’ Lizard Among New Madagascar Species.”)
Half of the newfound reptiles may be extinct or nearly extinct, mostly due to introduced predators—such as the small Indian mongoose—and deforestation, noted Hedges, whose study was published April 30 in the journal Zootaxa.
The Anguilla bank skink, which lives on the mongoose-free islands of Anguilla and St. Barthélemy (regional map), is a bit better off. But due to threats from habitat destruction and other invasive predators, such as the black rat, the study team proposes that the species be listed as vulnerable by the International Union for Conservation of Nature (IUCN).
—Christine Dell’Amore
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Bigger Gorillas Better at Attracting Mates and Raising Young
ScienceDaily (May 1, 2012) — Beauty may be in the eye of the beholder, but even for gorillas, some traits stand out. A new study conducted in the rainforests of the Republic or Congo shows that female western lowland gorillas seek out bigger mates to father their offspring.
--- 1 month ago --- 8 notes ------ 1 month ago --- 126 notes ---Best Underwater Pictures: Winners of 2012 Amateur Contest
1. Overall Winner. A headshield sea slug pauses on a blade of grass in the U.S. Virgin Islands in the winning image of the University of Miami’s 2012 amateur Underwater Photography Contest, whose results were announced this month. Photograph courtesy Ximena Olds, RSMAS
2. First Place: Marine Animal Portrait. Young Sperm Whale. Photograph courtesy Douglas Kahle, RSMAS
3. Second Place: Marine Life Portrait. Scorpionfish. Photograph courtesy Rockford Draper, RSMAS
4. Second Place: Student Photography. Harlequin Shrimp. Photograph courtesy Philip Gillette, RSMAS
5. Third Place: Marine Life Portrait. Purple Nudibranch. Photograph courtesy Nicholas Samaras, RSMAS
6. Third Place: Macro Photography. Emperor Shrimp. Photograph courtesy Marcello Di Francisco, RSMAS
7. Fan Favorite. Jellyfish. Photograph courtesy Todd Aki, RSMAS
Giant Squid’s Basketball-Size Eyes Have Sperm Whale Vision
If colossal and giant squid’s basketball-size eyes—two to three times bigger than any other animal’s—don’t see particularly well, what’s their evolutionary point?
According to a new study, big squid eyes do have a “superpower” Captain Ahab might have killed for: sperm whale vision.
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Male Panther Chameleons can grow up to 20 inches (50 cm) in length, with a typical length of around 17 inches (45 cm). Females are smaller, at about half the size. In a form of sexual dimorphism male Panther Chameleons are more vibrantly colored than the females. Coloration varies with location, and the different color patterns of Panther Chameleons are commonly referred to as ‘locales’, which are named after the geographical location in which they are found. Panther Chameleons from the areas of Nosy Be, Ankify and Ambanja are typically a vibrant blue, while those from Antsiranana and Sambava are red, green or orange. The areas of Maroantsetra and Tamatave yield primarily red specimens. There are numerous other color phases, and patterns differ between and within regions. Female Panther Chameleons generally remain tan and brown with hints of pink peach or bright orange, no matter what region they are from, but there are slight differences in patterns and colors among the different color phases. - Wikipedia
(Source: neuroconnoisseur)
--- 2 months ago --- 13 notes ---Snakes on an Inclined Plane Control Scales to Climb
Whether a serpent tempted Eve to eat apples from the Tree of Knowledge is up for debate, but now we understand better how it could have climbed the tree in the first place. It seems snakes can control each of their scales individually to grip rough surfaces and fight gravity.
Biologists have long known that snakes’ scales are good for gripping. Their scallop-shaped geometry and the way they lie over each other like Venetian blinds help stop them sliding backwards.
Now Hamid Marvi of the Georgia Institute of Technology in Atlanta and colleagues have found that snakes can also control each scale. “[Biologists] knew about the passive mechanism, not the active one,” he says.
“I’m not aware of previous published research showing active control of individual scales,” agrees zoologist Harry Greene of Cornell University in Ithaca, New York.
Marvi and fellow researchers sedated an albino corn snake and let it slip, unconscious, down a ramp. They measured the angle at which they had to tilt the ramp to get the snake to slide, which revealed the coefficient of friction between the snake and the ramp.
Awake snake
They repeated the experiment with an alert snake and found that the coefficient of friction was twice as large as when it was asleep. That suggested it could do something to improve its grip.
“When the snake is unconscious, there is no control, no feedback, no sensory system,” Marvi said at a press briefing at this week’s American Physical Society conference in Boston. “But when the snake is conscious it can sense, ‘I’m sliding, so I should do something.’ There’s an active mechanism involved.”
Indeed, when the team took close-up videos of the snakes’ soft underbellies, they found the snakes can control the angle of each scale to most effectively stick to a surface. “By controlling the initial angle of attack of the scale, snakes can increase their friction,” Marvi says.
Armed with this knowledge, Marvi and colleagues built a climbing robot called Scalybot, which could be used for search and rescue work, he suggests.
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