Blogger Widgets Desktop HD Wallpapers Free Downloads: February 2014

Thursday 27 February 2014

Black Cat HD Wallpapers

About Black Cat

A black cat is a feline with black fur. It is not a particular breed of cat and may be mixed or a specific breed. The Bombay, known for its sleek black fur, is an example of a black cat. The all-black pigmentation is slightly more prevalent in male cats than female cats. Their high melanin pigment content causes black cats to have yellow (golden) eyes (irises).
Any cat whose fur is a single color, including black, is known as a "solid" or "self". A "solid black" cat may be coal black, grayish black, or brownish black. Most solid colored cats result from a recessive gene that suppresses the tabby pattern. Sometimes the tabby pattern is not completely suppressed; faint markings may appear in certain lights, even on a solid black cat. A cat having black fur with white roots is known as a "black smoke."

Black cats can also "rust" in sunlight, the coat turning a lighter brownish shade.
A black cat "rusting" (coat turning a lighter brown shade) in sunlight

In addition to the Bombay, The Cat Fanciers' Association allows solid black as a color option in 21 other breeds. The color description for those breeds is:

    Black: dense coal black, sound from roots to tip of fur. Free from any tinge of rust on the tips. Nose leather: black. Paw pads: black or brown.

The exceptions are:

    Oriental - EBONY: dense coal black. Free from any tinge of rust on tips or smoke undercoat. Nose leather: black. Paw pads: black or brown.
    Sphynx - BLACK: black. One level tone from nose to tip of tail. Nose leather: black. Paw pads: black or brown.
    Ragamuffin - Although black is not specifically mentioned, the standard allows for "any color, with or without white," so technically speaking, an all-black Ragamuffin would be allowed under the breed standard.
























Tuesday 25 February 2014

Beautiful Birds on Branches

About Birds on Trees

You ever see a bird clutching onto a branch high in a tree and wonder, "What happens if it falls asleep? How could it hold on?" 

The avian talon works through a "pulley system of tendons," according to the animal morphology blog Ars Anatomica, and it can lock into place. 

"The bird's foot closes and grasps automatically as the ankle and knee joints are bent," we read. "This grasp cannot be released until the limb is straightened again." 

So, instead of expending precious energy holding the muscles tight—as you would if you were hanging onto a branch with your fists/arms—the system simply physically locks in place. 

A 1990 paper in Zoomorphology goes into more depth about the biomechanics of the lock, which results from the placement of the tendons and evolved specializations of their texture. 

And, of course, this wondrous anatomical system doesn't just come in handy on telephone wires, but also during attacks:

    Raptors swoop down on prey with talons/legs outstretched. The impact with the prey folds the raptor’s legs against its body, causing the talons to clench automatically, tearing into the prey. The automatic grip is strong enough to kill, and is what allows many hawk species to catch and kill other birds in midair.