Taxonomy Explained
“A beautiful and cheerful portion of created nature consisting of animals having a body covered with feathers and down; protracted and naked jaws (the beak), two wings formed for flight, and two feet. They are aereal, vocal, swift and light, and destitute of external ears, lips, teeth, scrotum, womb, bladder, epiglottis, corpus callosum and its arch, and diaphragm.” - Carl Linnaeus, Systema Naturae (1758)
Scientific names: those which some labour to memorise because it was required in school - are they important?
Yes, they are. Are they a permanent, infallible guide to a species? No, they are neither infallible nor permanent, but they certainly are a very helpful guide.
In this post I’ll be talking about all the fuss about changing classifications and scientific names, along with how it affects the way we see biodiversity. Hopefully it’ll clear up some of the technical details I sometimes sneak into my articles. You don’t have to read this if you do understand the technical stuff (especially if you’re a birder yourself), but if you don’t, I hope this will clear things up.
People have been classifying things since time immemorial. Early humans would’ve classified plants as edible and poisonous, and animals as hunters and prey. Ancient scholars around the world classified just about anything, from the stars to rocks to medicines, to different levels of accuracy.
There are arbitrary forms of classification, looking merely on the surface. For example, the term shellfish can refer to a bunch of shrimps, prawns, crabs, crayfish - plus clams, mussels, sea snails and oysters. Two completely different groups of animals when scientifically classified, simply lumped into one net because they’re sea creatures with shells. And none of them are actual fish!
The first person in history to try a near-scientific form of classification of all living things was the Greek philosopher Aristotle. He realised, while studying marine life, that a simple lumping of living things based on first impressions is not accurate. For classification to make sense, one must deeply study the nature of the living thing in question, and see what characteristics it has in common with its own kind, and what sets it apart from others. Variable characteristics within the group have to be found out and removed from consideration when setting the group apart. Aristotle even organised living creatures into a hierarchical order, from simplest to most complex.
The next person to make a breakthrough, and whose work is the foundation of scientific classification, was Swedish botanist Carl von Linné - known to most as Carl Linnaeus. He put forward the idea of a two-part universal name, to be given to each species, a system now called binomial nomenclature. The name would be always written in the Latin alphabet, italicised in type and underlined in handwriting, with a special arrangement of capitalisation, and would be unique to a species no matter how many common names it had.
Butorides striatus Linnaeus, 1758
(Little Green Heron, Little Heron, Striated Heron, Green-backed Heron)
Linnaeus also formed the foundation of modern biological taxonomy - the science of naming, defining and grouping living organisms based on common characteristics. The widely accepted present day hierarchy, based on what Linnaeus built, goes as follows, with the Peregrine Falcon for example.
Domain - Eukarya (organisms with an organised nucleus in their cells)
Kingdom - Animalia (multicellular eukaryotes that obtain nutrients from organic sources)
Phylum - Chordata (animals with a notochord or vertebral column)
Class - Aves (birds: warm-blooded vertebrates with feathers and toothless beaked jaws)
Order - Falconiformes (small to medium sized birds of prey)
Family - Falconidae (falcons and caracaras)
Genus - Falco (true falcons, kestrels, hobbies and merlin)
Species - peregrinus (Peregrine Falcon)
These are not the only groups (scientifically known as taxa) that help categorise living organisms. Taxa can be divided into subgroups (such as subfamily Falconinae, which excludes caracaras), or even clumped to form supergroups.
One of these divisions is the subspecies, commonly known as the “race”. The Peregrine Falcon is divided into 19 subspecies according to the 1994 Handbook of The Birds of The World. The nominate subspecies is the one named first; in this case, Falco peregrinus peregrinus, found in the temperate parts of Europe and Asia. In South Asia we find the resident Shaheen Falcon, F. p. peregrinator, while F. p. calidus is a winter migrant.
The naming and division of species and subspecies, and even larger taxa, are absolute as long as they are not under scientific debate - which is not rare at all. Breakthroughs in genetic studies and the evolution-based concepts of phylogenetics and cladistics continue to change the existing system.
For example, the Black-rumped Flameback, Dinopium benghalense. It is a medium-sized woodpecker commonly found in the Indian subcontinent with a red crest, black throat and rump, and a beautiful golden back.
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| Black-rumped Flameback, Kerala, India. (C) Koshy Koshy (https://creativecommons.org/licenses/by/2.0/deed.en) |
In northern Sri Lanka lives its similarly golden subspecies, Dinopium benghalense jaffnense. However, birders in most of Sri Lanka are familiar with a version with a uniquely bright red back: Dinopium benghalense psarodes.
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| Red-backed Flameback, Thalangama Lake, Sri Lanka |
Genetic and phenotypic studies conducted by researchers now say that the red-backed flameback is best classified as a full species (although some disagree, due to limited hybridisation with the northern race). Thus, this bird is now named Dinopium psarodes, the Red-backed Flameback or Lesser Sri Lanka Flameback, endemic to the island. Its relative, the endemic Crimson-backed Flameback (Chrysocolaptes stricklandi) is a similar case, among so many others.
Taxonomy can be confusing in its shifting nature, but science is always a field that updates itself and deals with new knowledge, debating it and weighing its possibility. I hope this article explained the basics of taxonomy and its evolution well enough, so that diversity and endemism can be better understood.
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