Temas-Biología: Las tortugas antiguas y maravillosas

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Ancient & Marvelous Turtles

vía Dark Roasted Blend de Avi Abrams el 18/08/11

"QUANTUM SHOT" #720
Link - article by Avi Abrams

Secret of their survival? -
They go inside their shell for a long time and THINK.
Then, they ACT. Or rather, don't.

Turtles are old species. How old? They existed before mammals, birds, crocodiles and lizards... some say even before the dinosaurs themselves, well into the Triassic period (more info). They survived Triassic–Jurassic and Cretaceous–Tertiary extinctions (while also learning to retract their heads into shells) and are holding their own very nicely today.

Baby turtles are perhaps the most adorable baby reptiles. Here is an albino turtle born in Brazil:

(image via)

From tender young age, turtles grow old - up to 255 years old. Can you stand the weight of this gaze? This turtle knows something about life:

(original unknown)

Turtles display all sorts of emotion; from being curious, to being sad:

(originals unknown)

Perhaps little-known fact is that turtles are very sensitive creatures. They have great eyesight, wonderful sense of smell, good hearing and even extensive sense of touch (even their shells contains nerve endings)!

Alligator Snapping Turtle lives up to its name (it also features camouflaged tongue which looks like a worm - to lure in some hungry fish, and then... CHOMP!) -

(image via)

This delightfully aggressive specimen was caught in China:

(image via)

Eastern Box Turtle is a "state reptile" of North Carolina, has a nice "box" shell and a strange propensity to get hit by cars and agricultural machinery:

(images via 1, 2)

Snake Neck Turtle (also called Eastern Long-necked Turtle) looks like a broken creature, but it is perfectly fine. It is also a known "stinker" as it emits an offensive smelling fluid from its musk glands when threatened:

(images via 1, 2)

This is the Reimann's snake-necked turtle from New Guinea, one of the threatened freshwater species (see here)... it also smells like a skunk:

(photo credit: Joel Sartore, National Geographic)

Well, hello there! It does rather look like a toy.

Galapagos Tortoise: Giants on the Move

Advance the Tank Squadron!

(image via)

Once upon a time there was an Aldabra Giant Tortoise called Adwaita. This mighty male of the species died in 2005, living to be 255 years old! - one of the oldest living animals in the world (outside of 400 year old mollusks).

(images via)

Dreaming of the young world two hundred years ago:

(image via)

Aldabra tortoise live mainly on the islands of the Aldabra Atoll in the Seychelles, but there is a much better known variety of this giants. These are the Galapagos tortoise, reaching weights of over 400 kg and lengths of almost 2 meters! Riding them must be thrilling, though rather slow-paced fun:

(images via)

Apparently they like apples, and will reach for an apple with all their might... It is also a pretty awesome sight when they do battle:

(images credit: Tui De Roy, National Geographic)

The Galapagos tortoise Nigrita watches her cub in the zoo of Zurich, Switzerland (left image) - and the one on the right is just resting:

(images via)

Soft Shell: "Home, Sweet Home", the Utmost in Comfort Fit

Indian Flapshell Turtle looks out of the really soft and flappy shell:

(images via 1, 2)

In fact, these shells look like weird soft blobs (left image above), and hundreds are killed every year in the desert ponds of Rajasthan, India.

Here is another interesting looking specimen of softshell turtle from Cambodia... Cantor's Giant Soft Shelled Turtle, Pelochelys cantorii:

(image via)

Pig-nosed Turtle (Carettochelys insculpta):

(images via 1, 2, Ricardo Franca Silva)

Look me in the face! -

(image via)

It "flies" like some sort of a flappy-eared dragon:

(image via)

This Indian Flap Soft Shell turtle has a wonderful pinky pig nose and an intense gaze:

(image credit: Ray Shiu)

Spotlight Spiny Softshell Turtle (Apalone spinifera, formerly Trionyx spiniferus) - left image. On the right is an interesting shell pattern seen in Russia:

(images via 1, 2)

You can see many turtles varieties in the Royal Tyrell Museum in Canada:

(original unknown)

Turtle's Shell Plates are composed of skin. Lots of it.

The shell of a turtle consist of 60 different bones all joined together (forming top carapace and bottom plastron). The pattern on the shell is due to the fact that turtles only molt in patches, not discarding the whole skin like snakes do.

When seen as a cross-section, the turtle skeleten is largely empty inside:

So, how do turtles breathe, then? They can not expand and contract their shells;

"The rigid shell means turtles cannot breathe as other reptiles do, by changing the volume of their chest cavity via expansion and contraction of the ribs. Instead, turtles breathe in two ways. First, they employ buccal pumping, pulling air into their mouth, then pushing it into the lungs via oscillations of the floor of the throat. Secondly, by contracting the abdominal muscles that cover the posterior opening of the shell, the internal volume of the shell increases, drawing air into the lungs, allowing these muscles to function in much the same way as the mammalian diaphragm."

This pre-historic turtle skeleton makes you wonder how this creature looked in actual life (well, no, this is a piece of art, made by "creator of things that should not be"):