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Claw of the Cat, or How many Toes does a Cat have?

catclawThis morning my partner came into my Study and said “Shandy keeps shedding his Claws” and handed me a tiny interesting claw sheath.  I thought to myself “I wonder if that is normal” and “I wonder how much his claws are like our nails?”  Upon reflection, I thought sensibly that cats in the wild need their claws for climbing, hunting and defence.

I found the answers on  THIS  great page of Annie’s “Cat Talk 101” website.  For example, cat’s claws have outer layers called “claw sheaths”, which shed or fall off every few months, leaving behind a nice new sharp claw.  Cats don’t scratch to sharpen their claws, strictly speaking, but to get rid off the itchy old sheaths, which are the outer layer of their claws.

Some also say that cats scratch objects to calm themselves down and ease anxiety.

Apparently it is a myth that cats have got retractable claws.  Their claws are projectile and retractile rather than retractable, meaning they can extend and lengthen or poke out their claws or tuck them in or shorten them but not really consciously completely pull them into their paw pads.

The Claw I looked at is really a sheath of a tiny claw, as the claws renew and the outer husks of the old claw are shed.

The online Encyclopaedia Britannica says the following.

Claw, also called Talon ,  narrow, arched structure that curves downward from the end of a digit in birds, reptiles, many mammals, and some amphibians. It is a hardened (keratinized) modification of the epidermis. Claws may be adapted for scratching, clutching, digging, or climbing. By analogy, the appendages of other lower animals are frequently called claws. The claw’s shape is ordinarily suited to the food-getting habit of the animal. Eagles have long, curved talons for grasping prey; the claws of chickens are short and sturdy, for scratching the ground for food.

There are two mammalian modifications of the claw: the nail and the hoof. A nail is a broad, flat claw on the upper surface of the digit. It is present in mammals, such as primates, that use their appendages for grasping. A hoof is a short, thick structure that surrounds the end of the digit. It is present in various forms in the ungulates, which have a reduced number of digits. Hoofs are an adaptation for running.

Below is a link to pictures from the Children’s EB showing so-called “retractable claws” in action.

http://kids.britannica.com/comptons/art-53056/All-cats-except-the-cheetah-have-retractable-claws

You can see the claw sheathed but with the tip or point of the sharp claw still out from the paw pad, which actually means technically speaking that the claw is not FULLY RECTRACTED or rectractible if this word means completely withdrawn and completely hidden.

I have noticed Shandy cat’s claws sticking out a tiny bit and wondered if his claws really are retractable.  If you had a sharp Stanley Knife with a retractable blade, you would want the blade to be fully retracted into the tool when you store away the knife, not have a horribly sharp and dangerous tip sticking out even a little bit.

The difference between “retractable” and “retractile” is that a cat does not consciously stick out or tuck in its claws, as many people wrongly think.  However, when kitty ( or a big cat ) is relaxed and at ease, like when it is sleeping on someone’s lap, or walking, the claws are partly tucked away within the paw, because the flexor tendons attached to the claws are relaxed, and thus the claws are pulled back.  The tendons tauten to protrude the claw when a cat is alert or hunting, climbing or fighting.

However, I guess the kitty’s claws are withdrawn enough to describe them as retractable for most people.

Ligaments connect bone to bone, while tendons connect bone to muscle. The elastic ligament, pictured in red in the image above, pulls the distal phalanx close to the middle phalanx in order to keep the claws from touching the ground, working in tandem with the relaxed flexor tendon.

Cats walk on the tips and balls of their toes or “digits”.  This is known as digitigrade walking.  Each digit or toe has a claw, and there are usually five toes or digits on each cat forefoot and four on each hindfoot.

A cat’s and a dog’s paw pads are spongy pads of thick skin beneath each foot, assisting with silent movement and protecting the underlying bones and joints from injury during running and jumping.  Digitigrade walking combined with pads and small feet helps a cat move silently.

If you want to read about claws and how they evolved into nails, when Primates came along, please click on  THIS  link to a Google book titled “Mammalogy:  Adaptation, Diversity, Ecology”.

If you want to read about the hoofs or hooves of the “Ungulates”, please click on  THIS  link to “What is an Ungulate?”

By the way, DOGS do not have retractile or projectile claws, but they do walk on their toes, like cats.  Their claws are always exposed, and make dogs well suited to running.  Dogs run on their toes , and have four functional toes on both the front feet and the hind feet, and sometimes a fifth “dew claw” which serves no useful purpose, is not in contact with the ground, and is located higher on the inside of the leg.

You should NOT de-claw a Cat because that essentially means amputating part of her/his foot as opposed to trimming the claws.  We leave Shandy be, and don’t even trim his claws.  A dog’s claws become blunt with lots of walking on hard surfaces, so won’t need trimming usually.

 

catfiling

 

 

Your Animal Guide for 2014

Orca

Visit Carrie Hart’s Power Animals Unleashed site and venture into the   Enchanted Forest.    Before you enter the Forest, turn up your computer speakers to hear the gurgling brook, take a deep breath and ask to meet the animal whom can guide you throughout this year 2014.  When you are ready, click anywhere you are driven to click and your 2014 Power Animal will appear!!   Share your results here. Continue reading to find out how to find your own personal “Power Animal” and Animal Guides  …..

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Donate now to help bird conservation

golden-winged-warbler_robert-royce

Golden-Winged Warbler by Robert Royce

Please help the U.S. Cornell Lab of Ornithology to conserve the near threatened (IUCN listing) beautiful Golden-winged Warbler.   Please click on the link at the end of this post.

I am a member of the Cornell Lab, even though I live in Australia, because I love birds.  As a third year Biology student at the W.A. Institute of Technology years ago I studied the carbohydrate preferences of the sweet and tiny Brown Honeyater, Lichmera indistincta.  Thank you to the Cornell Lab of Ornithology and other organisations around the world for helping to save the birds.  Donate now and you will receive a camera lens cleaning cloth with a picture of the Golden-winged Warbler on it.

The site has fantastic resources available online, and as a member, you will receive their periodical magazine.  If you love birds, I recommend that you become a member, especially if you live in America.

The  Golden-winged Warbler  is a small, strikingly marked warbler, whom as a species is losing ground, both because of reforestation and displacement by the spreading Blue-winged Warbler.  The Golden-winged Warbler is declining dramatically in the Northeastern United States, and is listed as a Federal Species of Special Concern.

Donate now to help bird conservation

Endangered Jaguars – help stop the persecution

Jaguar painting by Jason Morgan

Jaguar painting by Jason Morgan

Original painting of the beautiful Jaguar by talented wild-life artist, Jason Morgan.  I have this print on canvas from Jason – you can order it too if you like by going to Jason’s website here.   In 2004 I had a black jaguar (panther) animal guide helper.   This page  here   explains the symbolism of the panther.

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Your Animal Guide for 2013

Visit Carrie Hart’s Power Animals Unleashed site and venture into the   Enchanted Forest.    Before you enter the Forest, turn up your computer speakers to hear the gurgling brook, take a deep breath and ask to meet the animal whom can guide you throughout this year 2013.  When you are ready, click anywhere you are driven to click and your 2013 Power Animal will appear!!   Share your results here. Continue reading to find out how to find your own personal “Power Animal” and Animal Guides  …..

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Ode to the Grasshopper

grasshopper

Grasshoppers and Crickets

The grasshopper is an insect of the suborder Caelifera in the order Orthoptera. To distinguish it from bush crickets or katydids, it is sometimes referred to as the short-horned grasshopper. Locusts are the swarming phase of certain species of short-horned grasshoppers in the family Acrididae, and are known to be pests sometimes. However, I wrote the poem below about the Grasshopper years ago, after I caught a baby grass-hopper in my Bug catcher, and then wanted to capture what I thought are the unique features of “the Grass-hopper.”

Around 18000 kinds of grasshoppers are known to humankind today and can be found across the globe, except the north and south pole regions, where the temperatures are extremely low. They are predominantly found in the temperate regions.  The biggest Grasshoppers are about 4.5 inches (11.5 centimetres) long. Their legs are long hind legs that are used for hopping and jumping. The short front legs are used to hold prey and to walk.

The grasshopper  has two large eyes called compound eyes, one on each side of its head.  They are composed of many hexagonal lenses, which may mean the insect perceives multiple pictures of the same image.   More likely, it means each lens picks up certain intensities or pixels of an image, and looking through all the lenses puts just one final image together.  The grasshopper has three simple eyes  located between its compound eyes. Simple eyes have only one facet. They can see the difference between light and dark only.  Compound eyes are a way of seeing more efficiently at the high velocities that some insects travel at.   The more lenses, the higher the resolution (or detail) of the image.

If you must know why an insect’s compound eyes are so large, please read this link   here  on “insect vision”, which I tried to do, but it made my head hurt (because it is rather technical).

A Grasshopper’s hearing organ is called the “tympanum” and is located on the abdomen.   The abdominal segments each have a tiny pin-hole called the spiracle, and together, the spiracles allow gas exchange.   Spiracles are tracheal openings in the exoskeleton of a spider (Arachnid) or insect, through which air is admitted and expelled.  They are equivalent to vertebrate lungs, and where human beings inhale oxygen through their noses, Grasshoppers inhale it through their spiracles!

Grasshopper Anatomy

Grasshopper Anatomy

Swarms of Locusts are sometimes confused with swarms of cicadas. Cicadas are actually from a different Order of Insects, being the Order Hemiptera.

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Bits and Bites – Teeth: Part One – General information

Source:    http://www.ket.org/trips/dentist/animalteeth.htm

Animal teeth are adapted for getting and chewing food. They can also be used for other purposes, such as protection or even building their homes!

Animals that eat meat are called carnivores. They have large canine teeth to hold and tear meat. Wolves, tigers, cats, and dogs are carnivores and have lots of sharp canine teeth. They need these strong, sharp teeth for catching and holding their prey. They bite their prey and tear the meat into pieces. They do not chew their food well, swallowing it whole or in large chunks. Some fish have teeth to help them catch their prey.

Animals that eat only plants are called herbivores. A herbivore’s long front incisors have sharp edges that are good for cutting grass and leaves. They have large molars at the back of their mouths for grinding and crushing the stems, leaves, fruits, seeds, and roots of plants. Their flat molars are used for grinding the plants. The long front incisors of beavers and squirrels can break into nuts and seeds. Squirrels crack nutshells with their teeth. (Don’t you try that!) Beavers, squirrels, and other rodents have teeth that keep growing all their lives. They sharpen their teeth by gnawing as they eat. Grazing animals such as horses, cows, and sheep need their large back molars for grinding up grass and grain.

Animals that eat both plants and animals are called omnivores. They have both canines and molars. Are you a carnivore, a herbivore, or an omnivore? Animals have a much simpler diet than people do.

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Bits and Bites – Teeth: Part Two – the Structure & Function of Human Teeth

anatomy of a human tooth

Extract from  Online Britannica

Tooth, plural teeth,  any of the hard, resistant structures occurring on the jaws and in or around the mouth and pharynx areas of vertebrates. Teeth are used for catching and masticating food, for defense, and for other specialized purposes.

The teeth of vertebrates represent the modified descendants of bony dermal (skin) plates that armoured ancestral fishes. A tooth consists of a crown and one or more roots. The crown is the functional part that is visible above the gum. The root is the unseen portion that supports and fastens the tooth in the jawbone. The root is attached to the tooth-bearing bone—the alveolar processes—of the jaws by a fibrous ligament called the periodontal ligament or membrane. The “neck” of the root is embraced by the fleshy gum tissue (a specialized area of connective tissue covered with mucous membrane that lines the mouth cavity). The shape of the crown and root vary among different teeth and among different species of animals.

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