Taxonomy
What is taxonomy?
Taxonomy is the classification of living things. The human race has an obssession with applying objects both inanimate and living into "groups", so it should come as no surprise that all living things that have been discovered have been grouped together with other living things that share similar attributes, for example "animal". From this point the animals are regrouped again. Some animals types share more attributes with some types than they do others, so these are put into another category, for example "mammals". This regrouping within a group continues until a distinct species can be defined. In the case of living things, this grouping system is referred to as "taxonomy". The basis of classifying living things begins with a generalised catergorisation for example plant or animal. From there on in the categorising system becomes rather complicated for those of us who suffer from a short attention span. For this reason I will be looking only at the classifications used in this website
Class
As foresaid, animals are categorised under a variety of headings. The first category used in this website is the "class". There are 5 classes in which vertebrate animals can be grouped. These are classes are:
aves (birds)- warm blooded animals which have wings (but don't necessarily fly) and lay eggs
reptilia (reptiles)-cold blooded animals that give birth on dry land
amphibia (amphibians)-cold blooded animals that give birth in water
mammalia (mammals)-warm blooded animals that have mammary glands (nipples) and produce milk to feed their young
picses (fish)-cold blooded animals that breath oxygen filtered from water through gills
Order
The catogary that is used after 'class' is refered to as the 'order'. Since this website is concerned only with mammals I will only be discussing mammalian orders, and only those mammalian orders used on this website. These are:
Perrisodactyla- The word "perrisodactyla" means "odd number of toes". Animals included in this order are horses. Generally this order refers to hooved animals with an odd number of toes.
Artiodactyla- The word "artiodactyl" means "even number of toes". Animals included in this order are sheep, cattle, goats, deer and pig. Generally hooved animals that have an even number of toes
Carnivora- These mammals have long canines, and cheek teeth that are modified for chewing animal matter. These animals feed mostly on meat. The badger (Meles meles) is an exception to this rule. Although it has the dental pattern of a carnivore, it's dietry habits are omnivorous. Cats, dogs, weasels etc are all typically carnivorous (meat-eaters) therefore belong to this order.
Rodentia- Rodents are characterised by their long chisel like incisors (2 in the top jaw and 2 in the mandible) which are used for gnawing. These animals also have a distinct gap between the incisors and their cheek teeth. This gap is known as the diastema- rats, mice, voles, squirrels etc.
Lagomorpha- Lagomorphs share the characteristics of the rodent. They differ in the fact that they have a second, smaller pair of incisors lying behind the first pair in the upper jaw- rabbits, hares
Insectivora- Insectivores feed mostly on insects. These mammals are characterised by their pointed cheek teeth -hedgehogs, moles, shrews etc
Cetacea- These are mammals that live and reproduce in water- whale, dolphin, porpoise.
Family
Each animal within a given order is rebunched into a series of new groups according to how closely they are related on the evolutionary path. For example the carnivora order is seperated into animals which are cat-like, dog-like, weasel-like etc. Lets look at those animals that are refered to as being dog-like. These animals include dogs, wolves and foxes. This is a family of animals that are closely related but may differ in behavioural patterns and habitat preference, yet they have very similar skeletal characteristics and eating fashions. The family of the dog-like animals are known as the "canidae" family. The Families that we are looking at in this website are:
Canidae- the dog family which includes dogs, foxes and wolves.
Felidae- the cat family which includes tigers, lions, domestic cats etc.
Mustelidae-the weasel family which includes weasels, stoats, badgers, polecats, ferrets, martens etc.
Talpidae -the mole family
Leporidae-the rabbit family which also includes hares
Erinaceidae -the hedgehog family
Scuridae -the squirrel family
Muridae -rats and mice
Cervidae -Deer family
Bovidae -cattle, sheep, goats etc.
Microtidae -voles
Please note that this website will only be dealing with the family representatives that are native to Britain and those that have been established in Britain long enough to be refered to as British species, as well as popular British pets.
Scientific names- genus and species
Every living thing has a scientific name, this special name is refered to as a Linnaean binomial. The word Linnaean comes from the name Linnaeus (the person who invented the system), the word binomial probably comes from the latin word binominis which means with two names. All Linnaean binomials consist of two names. the first name refers to the genus and the second name defines the species. These two names that make up an individual species are always in Latin words. If an appropriate Latin word isn't available as in cases when a living thing is to be named after the person who discovered it, the non-latin word is "Latinised" this is like writing, or speaking english (or any other language) with a latin accent!
So why do living things have two names and why are in latin?
The method of naming living things is useful to distinguish a particular species when the use of common names becomes confusing. Some species have several common names. The brown rat is a classic example often refered to as the common rat, the Norway rat or the sewer rat. Although it has several different names they all refer to the same species of animal with one Linnaean binomial- Rattus norvegicus. Not to be confused with Rattus rattus whose common names include black rat, ship rat and plague rat . This isn't just a British problem, all countries have their own vernacular (common) names for individual species. Once of a day Latin was a language that was understood world wide, particularly amongst academics, so it made sense that all living things should have their scientific name in Latin, this way scientists all over the world would know they which living thing another was talking about. The purpose of a living thing having two names is to identify how closely one organism is related to another. Animals that share the first part of their scientic name (genus) with that of another are even more closely related than those of the same family. Those animals which belong to the same genus are so closely related that given the opportunity, they can successfully interbreed to produce fertile young known as hybrid species. For example the domestic cat(Felis cattus) and the Scottish wild cat (Felis sylvestris) are two different species, yet they share the same genus-Felis. These two species are so closely related that it is now become difficult to tell the difference between domestic cat/wild cat hybrids and pure scottish wild cats. The second part of the name (species) tells us that these two animals are not exactly the same, they may behave slightly different, or they serve a slightly different purpose in nature, for example they may specialise in hunting different animals.
Subspecies
Subspecies can be very confusing, the best defintion I can give is a "species within a species". Animals that are described as being a subspecies to a particular species are usually minority groups of a species that are in the process of moving up the evolutionary ladder. For example lets look at the carrion crow (which incidently is a bird, not a mammal, but since it was the first example of sub species to spring to mind I'll use it). There are two types of carrion crow in Britain. The primary species being Corvus corone - these are large carrion eating birds with black feathers tinged with metallic blue (the metallic blue is generally only visible at close range and in the right lighting), these birds are present throughout Britain. Further up north (Scottish region, and also Ireland) the carrion crow is distinctively different, it remains the same species Corvus corone, it can interbreed with Corvus corone (where their territories overlap), its behaviour is the same, its eating habits are the same, even the skeletal structure is the same, but it has adopted a minor change- this change is in the colour of its plumage. Unlike the black carrion crows further down the island, the carrion crow of scottish regions are grey bodied. Because of this minor trait they are refered to as hooded crows. They are in every way the same as carrion crows, therefore cannot be defined as a seperate species, yet the taxonomists of the world feel that this geographical difference is worth defining the hooded crow from the carrion crow by applying it to a supspecies. In this case the hooded crow is scientifically refered to as Corvus corone cornix. In brief, a subspecies is a small group of a primary species that has made a minor evolutionary change in order to adapt to a geographical difference that isn't present where the majority of the primary species inhabits. Of course this is only my interpretation of subspecies and I can't guarentee that I am correct.
What is the purpose of taxonomy?
The idea behind taxonomy (or the classification of living things) is that any living thing will have one and only one correct name that isn't shared with another living thing.