Friday, 10 April 2015

How to Identify Ants? (Part1)

Let us get it straight, ants are damn small, dull and potentially offensive due to their bites and stings. They are small enough to hide most of their beautiful features and that is a primary reason why every ant is either a black ant or a red ant to a common man. Added to this the woeful childhood experience of been stung or bitten by some pugnacious ant, again goes against the image building of this group. Compare that with a butterfly. They are big (bigger than ants), are extremely colourful in most cases and catch our attention instantly. It is as if they are walking PR stunts and to top it off are associated mostly with love and romance (No offence  my lepidopterist friends)! The below image explains this well.

Comparison of Jerdon's Jumping ant and Common Imperial butterfly photographed at 150mm

The game though entirely changes when you zoom in a bit on ants (optically). Those fine ridges, striations, spines, pubescence and other wonderful morphological features that are usually not seen to the normal human vision becomes evident.

Jerdon's Jumping ant | Harpegnathos saltator (T. C. Jerdon, 1851) seen at a 1:1 zoom ratio at 90mm

Till a few years ago, this wonderful group was restricted only to a few who had access to microscopes but with the advent of macro photography both at the higher and at lower end, people have started to show their interest towards ants. They are able to appreciate the world of this hitherto neglected group more and the levels of curiosity are on a steady rise. No more is this the domain of just educational/ research institutes in India, since a new breed of enthusiasts are coming up just on the lines of birdwatchers and the term ant watchers doesn't sound very bad either!

Few days ago an online friend Deepak Deshpande on an online forum, asked me “how to go about identification of ants?” For almost three days I have been constantly thinking, how best do I answer to him and then thought about attempting to make a series of posts which will help in identification of ants to a basic level. This post, which will be the first of the series, will have a general description about ant taxonomy and steps to identify ants till sub-family level.

Before I start, I would like to drop in a few lines regarding the general position of ants in the animal kingdom. I will assume that most of you know general biology but still I have tried to make it as simple as possible and will start with the systematic position.
Systematic position of ants in Animal Kingdom.

Many have also asked me if ants are related to bees or wasps and the below diagram will be useful in understanding that.

Phylogeny of order Hymenoptera

The next question to address is how to differentiate ants from wasps or bees? There are three distinct features which an ant has and distinguishes it from its cousins the wasps and the bees, they are: geniculate/ elbowed antenna, metapleural gland and a petiole which separates the thorax from the abdomen. The below diagram will be useful for to visualize these features better.

Characteristic features of an Ant

For a more detailed and descriptive sketch of the morphology of an ant refer to the below image:

Ant Morphology

Looks scary right? So let us start with some very basic parts of an ant which we will be using in trying to key them down till subfamily level.

Ant Morphology for Beginners (side profile)

Ant Morphology for Beginners (head)

Now that we are familiar with the basic parts of ants, let us attempt the next step. What follows below is a simple key to identify ants till subfamily level. 

Instructions for use:
Look at your photograph of any ant closely and read the first line of this key. 
If the description matches that of what is in your photograph go the the next numbered line which is mentioned in the brackets. 
Please note that there are 10 subfamilies of ants described from India and this post will help you identify only the 5 most encountered subfamilies.

First glance through this post and you will think this is extremely tough and you might also be feeling that you probably wasted your time, but believe me this is very rewarding if you are genuinely interested.
There is another short cut way to identify ants and that is to use a picture guide. The best pictorial field guide as of now in the market is “On a Trail With Ants– A Handbook of The Ants of Peninsular India by Ajay Narendra and Sunil Kumar M” which has around 50 common species photographed and described in it. 

But as an afterthought if you are serious about identifying ants, the best thing to do is get familiar with taxonomic keys because a pictorial field guide for ants will limit you to only what is represented in the guide while going systematically using keys will open up the world of ants for you with almost no restrictions.

Before I conclude this section, just a few words of suggestions:

  • You need patience and perseverance to develop necessary skills for identification and taxonomy of not only ants but any other taxa in the living world, be it the humble grass or the charismatic tiger.
  • Regular exposure to this taxon (ants) is what will get you there.
  • Colour is not a very good tool for identification when it comes to ants and hence there is no black or red ant.
  • Always remember that every statement/ natural history observation will always have an exception so be open to surprises.
  • Nothing in natural history studies is full and final; there is always scope for learning in even the most widespread and commonest observations.

Please do give me your suggestions if you found this useful or if you need any edits to be made which will make it more easy.

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