{"id":28,"date":"2012-11-24T03:39:46","date_gmt":"2012-11-24T03:39:46","guid":{"rendered":"http:\/\/www.howiewatkins.co.uk\/content\/?p=28"},"modified":"2012-11-25T16:08:12","modified_gmt":"2012-11-25T16:08:12","slug":"classification","status":"publish","type":"post","link":"https:\/\/www.howiewatkins.co.uk\/?p=28","title":{"rendered":"When is a bird a fish?"},"content":{"rendered":"

Look at the picture.\u00a0 You might recognise the bird as a puffin, but even if you didn\u2019t, I bet you still recognized that it\u2019s a bird, and would probably be a little surprised if I told you that it is actually a fish.\u00a0 Confused?\u00a0 Well there is an explanation\u2026<\/p>\n

Traditionally, Christians avoided eating meat during the festival of Lent and on Fridays (a ritual still practised by many today).\u00a0 However, they were free to eat fish if they wished.\u00a0 For the inhabitants of Northern Scotland, for whom the puffin was a major part of their diet, not eating them presented serious problems (the Lent festival lasts 40 days).\u00a0 To help out, the church authorities ruled that puffins, because they spend so much time underwater, were not birds, but were, in fact, fish, and could be eaten.\u00a0 Good news for the puffin-eaters, bad news for the puffins.<\/p>\n

What\u2019s in a name?<\/h1>\n

The puffin story is a great example of how the naming and classification of living organisms can make a big difference to how we treat them, but there\u2019s more to classification than that.\u00a0 The ability to recognize and sort things is a vital survival skill, and\u00a0isn’t\u00a0limited to humans.<\/p>\n

The bright markings of the poisonous monarch butterfly that warn predators not to eat it; the black and yellow \u201cdanger\u201d stripes of a wasp; the rainbow colours of a South American, poison-arrow frog; these all work because the potential predators learn the significance of the patterns and file them in their memories as dangerous.<\/p>\n

The ability to identify plants as either edible or poisonous; to tell the difference between a lion (harmful) and a sheep (edible); to recognise the warning hiss of a snake; these are all vital skills that have developed because they lead to a long and successful life.<\/p>\n

Aside from the value of classification as a survival tool, we humans have taken it to extra-ordinary lengths.\u00a0 The science of taxonomy, a branch of biology dedicated to the naming of living thinks is the ultimate refinement of this.\u00a0 So far, we have identified around one and a half million living things, and sorted them into groups.<\/p>\n

You are already pretty good at classifying living things, animals in particular (you can probably recognise and name several hundred).\u00a0 But this is really the tip of the iceberg.\u00a0 If you want to really study biology, you\u2019ve got to get to know a bit of taxonomy.<\/p>\n

What\u2019s that bird called?<\/h1>\n

Identifying different types of plants and animals in a way that could be understood by all became important the minute scientists wanted to start sharing information.\u00a0 The ancient empires of India, South America (the Aztecs), China and North Africa (The Egyptians) all developed systems for classifying the natural world.\u00a0 The biggest impact on Western science was, however, the recorded work of the Greeks and Romans.<\/p>\n

Over two thousand years ago, the Greek philosopher, Theophrastus wrote \u201cEnquiry into Plants\u201d and \u201cThe Causes of plants\u201d.\u00a0 He wrote about over 500 kinds of plants, and Alexander the great sent him specimens from the land he had conquered so that they could be studied.<\/p>\n

The work of the Ancient Greeks was continued by the next great empire builders, the Romans.\u00a0 Pliny the Elder wrote a hugely influential book, \u201cNatural History\u201d, dealing with the medical and agricultural uses of plants.\u00a0 Another Roman philosopher, Dioscorides followed this with \u201cMateria Medica\u201d, a book that listed and, for the first time, grouped together over 600 plants useful in medicine.\u00a0 Amazingly, this remained the most comprehensive work on the subject for nearly 1500 years.<\/p>\n

Too many names<\/h1>\n

During the seventeenth and eighteenth centuries, explorers who had voyaged from Europe, returned with incredible numbers of plant and animal specimens that had never been seen before.\u00a0 The job of naming them all and describing them fast become a major headache.\u00a0 Scientists realised that it was time to get organised.<\/p>\n

There are two reasons why scientists try to be organised about the naming of living things.\u00a0 Firstly there are too many for any one person to learn the names and descriptions of them all.\u00a0 Secondly, for many, there is a different name in every language.\u00a0 If I were to talk to one of my French friends about the badgers that live in the woods by my house, they wouldn\u2019t know what I meant.\u00a0 If, however I used the French word Blaireaux, they\u2019d understand me.<\/p>\n

Credit for solving the classification headache goes to the Swedish scientist Carl Linnaeus.\u00a0 In 1735, he invented the Binomial (literally, two-name) identification system that, with revisions, we still use today.<\/p>\n

Linneus proposed that all animals and plants should have a \u201cscientific\u201d name that everyone would understand and use.\u00a0 To prevent arguments, he based these names on Latin and Ancient-greek.\u00a0 The use of Latin didn\u2019t cause problems because, at that time, all scientists learnt Latin so that when they wrote to each other they could use a common language.<\/p>\n

The really clever thing about the Linnean system was the way he sought to place organisms in groups based on their similarities.\u00a0 Under his system, a lion, became Panthera leo.\u00a0 Notice how I have written the name in italics, this is so that scientists \u2013 that\u2019s you by the way \u2013 can spot straight away that I have written a scientific name and not a common name.\u00a0 The second word, leo, is the unique \u201cspecies\u201d name of the lion.\u00a0 The first word, is the \u201cgenus\u201d, or group of similar animals to which it belongs.\u00a0 Just by looking at the name, I can make an educated guess about the kind of organism it is referring to, even if I\u2019ve never seen it.\u00a0 For example, do you know what a \u201cTendwa\u201d is?\u00a0 I thought not.\u00a0 You probably wouldn\u2019t recognise this animal by its scientific name Panthera pardus either, but that doesn\u2019t matter, because you know that if it\u2019s in the Panthera \u00a0group, its going to be quite like a lion and therefore not something you want to play with (in English, its called a leopard by the way).<\/p>\n

Happy families<\/h1>\n

Linneus didn\u2019t stop at grouping things by Genus, he built larger and larger Taxa (groups), so that each scientific name became like a postal address that identified exactly where on the tree of life an animal or plant should be placed.\u00a0 This innovation was the principal reason his classification system caught on, and is still used.<\/p>\n

Stop for a second and think about how a postal address works.\u00a0 If my friend Theresa wanted to send me a postcard from Australia, where she now lives, she would write my address on it: Howie Watkins, PO Box 15, Neath. Wales. UK.\u00a0 When she posts it, it will be taken to the local post office and sorted.\u00a0 The person who sorts the mail in her town wont know who I am, and may not even have an idea where Wales is, but will know where the UK is and will stick the card in the next bag of mail heading in that direction.\u00a0 When the bag is opened at the airport, it will probably be opened by someone who doesn\u2019t know me either, but they\u2019ll know where Wales is, and they\u2019ll send it another step closer.\u00a0 The mail sorters at Neath Post Office do know who I am, and do know where PO Box 15 is, so they\u2019ll deliver the card.\u00a0 The system works, even though it\u2019s impossible for one person to know the exact location of everyone else on the planet.<\/p>\n

To see how a scientific name works in the same way, here\u2019s the full name for an African Lion: Animalia, Chordata, Vertebrata, Mammalia, Eutheria, Carnivora, Felida, Panthera leo.\u00a0 That\u2019s a bit of a mouthful I know, so here it is, step by step.<\/p>\n