Published on June 2nd, 2011 | by Yellow Magpie0
The Squirrel: A Varied And Clever Creature
Fleet of foot, the squirrel is an arresting creature that displays presence of mind and great planning in its bid for survival. Their terrific memories and adaptability makes these animals extremely interesting.
Squirrels are a sub-group of rodents. There are thought to be at least 278 different species which include groundhogs and prairie dogs.
It’s All In The Tooth
Like the beaver, squirrels have self-sharpening teeth. They do most of their biting with their large incisors which grow continuously. The teeth are composed or two layers, the front is made of enamel while the back is composed of softer dentine. The dentine layer wears away first and because of this the teeth stay sharp.
They use their chisel-like teeth for eating and gnawing at tough materials like hazelnuts.
Similar Hands But Amazing Feet
The hands of squirrels are remarkably similar to our own. They have five digits and a rather small thumb on each hand. However, the ratios of the hands are much different from ours and their palms are relatively modest in comparison to the length of their fingers.
Depending on the species, the width of their hands varies. For instance, the burrowing squirrel’s hands are much wider than that of the tree squirrel. Which, no doubt, helps to assist digging.
What is truly astonishing is squirrels ability to turn their feet when climbing down. Whereas people normally can only move their ankles a few degrees without moving their legs, squirrels can move theirs 180 degrees independently of their feet. This feat is accomplished by unusually flexible ankle joints which allows the squirrel to descend smoothly.
The Difference Their Tails Make
The tail of a squirrel may be its single most important limb. While jumping they use their them as rudders to guide their direction. The tail also plays a critical role in climbing trees, helping the squirrel to control its centre of balance and keep a good footing.
If a squirrel falls, and they sometimes do, their tails act as parachutes reducing the free-fall speed. The tail also acts as a cushion protecting their delicate bones from a hard landing.
Nonetheless, there is more to squirrels’ tails than just balance and safety. Squirrels tails play a critical role in thermoregulation. Normally rodents tails are conical, as opposed to bushy like a squirrels, and have a lot of surface area but little volume. Rodents tails are rich in blood networks and squirrels are no exception.
Generally, this means that rodents lose a lot of heat through their tails which can cause problems in winter. Squirrels can control the temperature of their blood flowing through the tail. In winter their tails are supplied with cold blood which means there is minimal heat loss. While in summer the opposite occurs and they send warm blood through the appendage to cool them down.
What Do They Eat?
Squirrels generally eat nuts and tree buds. They cannot digest cellulose so eating grasses and such matter is out for them.
During the spring, when the nuts that they have collected start to sprout, they must look for an alternative food source. They usually choose to eat tree buds during this period.
There has been documented evidence of some squirrels eating infant squirrels, although this is thought to be rare. Other researchers have found small vertebrates such as lizards and rodents inside the stomachs of squirrels.
How Do They Remember Where They Stashed Their Food?
Squirrels are renowned for the nut-collecting behaviour. It is thought that they store their nuts in different places to prevent all of their food from being eaten. If one is discovered by a predator or rival the squirrel doesn’t lose its entire hoard.
They sometimes store nuts temporarily only to move them to a more permanent location. This is called ‘scatter hoarding’. Their long-term stores are sometimes called ‘larder hoards’.
This charming video explains how squirrels remember locations:
Red Versus Grey
In Ireland, as well as in the United Kingdom, there are two types of squirrels, the native red and the recently introduced grey. The grey is considered to be a pest in both areas and are actively culled as they are impacting upon the numbers of native red squirrels.
The grey squirrels also do damage to trees. Although, as of yet, it is still not known why they do this.
Squirrels are highly intelligent mammals. One of the hallmarks of intelligence is the ability to communicate. Squirrels do this through high pitched chatter using shrill sounds. They also use their tails to ‘talk’ to one another. Rapid flicking usually is a warning for other squirrels to keep their distance.
Squirrels are thought to be dichromatic.
Most people are trichromatic, we see through three different colour filters, red, blue and green. Dichromatic people and other animals are missing the green filter and therefore have red/green color blindness. As a consequence of this, squirrels cannot see colour in 3D.
Here is the a picture of the colours of the rainbow seen from the perspective of a squirrel.
- Squirrels can be different sizes according to the species. The smallest, the African Pygmy Squirrel, is only eight to ten centimetres (three inches) in length. While Groundhogs, a type of Marmot, can be over 80 cm in length (two feet six inches).
- They also vary in weight depending upon the species. One of the largest, the Groundhog, weighs up to 18 kilograms (31 lbs).
- In the wild, squirrels usually live up seven or eight years. In captivity they can live to be as old as twenty.
- They are found in every continent with the exception of Antarctica. Recently they have been introduced into Australia, where they are not native.
Highly Recommended Get The Book Through Amazon
Squirrels: The Animal Answer Guide is very interesting and informative read that is highly accessible to everyone. It takes a question and answer format, and answers questions that we would like to know about these remarkable animals.
You can obtain Squirrels: The Animal Answer Guide (The Animal Answer Guides: Q&A for the Curious Naturalist here from Amazon.
For people living in Ireland or the United Kingdom you can access Squirrels: The Animal Answer Guide here.
For those living in Canada you can obtain Squirrels: The Animal Answer Guide from here.
For Germany: Squirrels: The Animal Answer Guide (The Animal Answer Guides: Q&A for the Curious Naturalist).