NatGeo :: Fish Glow Green After Genetic Engineering

Zebrafish glow green under the microscope.
Photographs courtesy University of Exeter

Fish Glow Green After Genetic Engineering.

Genetics truly are amazing. These fluorescent zebrafish are helping scientists discover the affect of pollutants in the tissues based on the presence of endocrine disruptors.

For now, the fluorescent technology is limited to fish younger than six days old, because their skin has yet to develop pigmentation that would interfere with observing the fluorescence.

“The next phase is breeding these fish with a strain that lacks pigment in the skin,” which would allow the team to observe the fluorescent reactions in adult fish as well, Tyler said.

NatGeo :: Video — World’s Weirdest: Weird Killer of the Deep

I couldn't help using a picture from Finding Nemo.

Keeping to my love of strange animals, here’s a video featuring the unique angler fish. For the record, being a male angler fish, let alone being a member of the species in general, sounds like a horribly boring life.

Video — World’s Weirdest: Weird Killer of the Deep — National Geographic.

– Scientific Classification – 

The rest of the classification gets a bit foggy. You can visit Wikipedia if you’re interested.

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NatGeo :: Deep-Sea Creature Photos

As much as I love the ocean, I’m really glad I live on land. If I saw this thing staring at me…

Frilled Shark (Chlamydoselachus anguineus)

…I might die. The ocean is one of the regions of the world that I hope we never fully understand so we can find more cool and creepy things like this. (See the tags for a list of the species found in the link below.)

Deep-Sea Creature Photos — National Geographic.

ScienceNOW :: A Piranha-Proof Fish

Credit: Jacobs School of Engineering/UCSD

A Piranha-Proof Fish – ScienceNOW.

The arapaima is probably the luckiest fish in the amazon. It’s scales have found to be impenetrable to piranha teeth. They have been described as “living fossils” as they retain lungs and therefore still need to breathe air. The enormous fish can be over 8 feet long and weight over 400 pounds.

In an experiment conducted by Mark Meyers (University of CA) and his colleagues,

To mimic an actual Amazonian chomp, they cemented a piranha tooth to a machine that delivered a bite to several arapaima scales. The fang didn’t just ricochet off the armor, it shattered, the team reports online in Advanced Engineering Materials.

To learn just how the arapaima does it, the researchers had to take a closer look at the scales themselves.

So the researchers took a closer look at the scales using a scanning electron microscope and similar tools. The scales, they discovered, are double layered. On the inside, they’re made from sheets of collagen, a tough-yet-springy material found in joints and bones. But their exteriors, or the sides exposed to piranha bites, are rock hard. These surfaces are also made from collagen, the team realized, but those fibers have been cemented together with a mineral also popular in bone: calcium.

Arapaima scales are compared to our teeth. They may be covered by enamel, but the core is dentine and more pliable. This sort of cushioning can stop the formation of cracks produced by some sort of pressure.

Unrelated to the scales, I wonder if the retaining of lungs by the arapaima has anything to do with little predatory pressure. I’d be interested to see if, perhaps there were some sort of decline in other available food sources, the piranha could evolve to take advantage of the arapaima as a food source. This of course would assume that there would be ample time to develop such capabilities.

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“Virgin Birth” Record Broken by Hotel Shark

WIld Zebra Shark

“Virgin Birth” Record Broken by Hotel Shark.

A zebra shark in a hotel restaurant’s aquarium, has been producing offspring without any male contact for 4 years. This is done by a process called parthenogenesis, which is basically an asexual form of reproduction. The offspring aren’t identical clones since the shark DNA is recombined. Many different sharks can reproduce parthenogentically, including blacktips and hammerheads.