Saunter, or, On the Art of Imagination and Perception

A dried-up leaf. A rolled-up leaf. A blotchy leaf. A pooped-upon leaf. After seven months of no respite, I found myself looking at these enthusiastically. Everything moved. Everything was something. Something resembled something else. Sometimes, something tried to be something else. I may have been imagining things, who am I to blame? The soggy boughs, cloud-diffused skies, a slight mist, a faint song of the birds. Add to that the huddled trees, clustered canopies, a subtle breeze. I perceived things differently. Who am I to blame? A leaf tumbled up a tree in front of my eyes. Another flew off. One burst into ridiculous shades of colours.

The extravagant - or ridiculously colourful - Orange Oak Leaf (Kallima inachus) butterfly
of Kanha Tiger Reserve.

Someone, somewhere, imagined that this butterfly looks like the leaf of an oak. Somewhere long before, something perceived a limbless leaf to be a safer bet than donning ridiculous colours. And then it decided, hey, why not have the best of both worlds? That took a million years of permutations and combinations, at least.

At the same time, somewhere something perceived looking like a rolled-up leaf with rotten edges. Elsewhere, something decided to look like shrivelled up flowers, or leaves, or twigs. And they decided that this is it, we will be this. Someone – to be precise, me – started seeing every rolled-up leaf or twig as a caterpillar.

A rolled up leaf, some shrivelled flowers, a Common Mormon butterfly caterpillar, and
a Hooktip moth caterpillar - all one and the same thing.

Call me a fool if you don’t see it, but in the clutter of the real world, a rolled-up leaf just might have an actual caterpillar inside, or be a caterpillar itself. This, like the oak leaf butterfly, is a strategy to go incognito. If this doesn’t work, the caterpillars such as that of some swallowtails (Papilio sp.) have false eyes on their backs, to resemble a tiny snake. If that doesn’t work, they expose a special organ called osmeterium situated right behind their heads – resembling the forked tongue of a snake, and if that doesn’t work, they exude a putrid smell to ward off anyone who dares mess with a rolled-up leaf; trust me I know, you can’t wash it off either. Caterpillars of the hooktip moth (Tridrepana sp.) trust their dry twig avatar with life, or sometimes regurgitate their acidic stomach juices to cause some irritation to the pesky intruder.

What are the odds you’ll find succulent caterpillars and not flaky leaf rolls? Well, these odds might not matter as much to you and me, they do to birds. An organism that gets regularly gulped or whacked by birds needs to look like an every-day object. What’s more common than leaves – wet or dried, in a forest? This increases the odds of survival for these callow critters, for I won’t expect every bird to eye every rolled-up or shrivelled-up leaf to be a juicy meal. In other words, a leaf-like insect would be like finding a needle in a haystack.

This Lappet moth tries to resemble a dry leaf stuck on a plant.
Not all hunters can see colourful images with a perfect depth-of-field.
To resemble what it might look like to a hunter, the black-and-white effect has been added.

As for me, I let my imagination run amock. It needed out after this hiatus. Every leaf was a potential critter trying to hide from me. Who are they to blame? I would photograph them, after all, but oftentimes, it would turn out to be a leaf stuck on a small plant, and sometimes, it would be a moth that not only tries to resemble a fallen leaf, but also sits on a plant as if it just fell there by chance. The cunningness of this lappet moth (Lebeda sp.) is interesting. It has fooled me at least a dozen times, I hope you can see why.

To put it simply, there are primarily two ways animals mimic others; they either mimic animate objects or they mimic inanimate objects. Insects that mimic animate objects – other animals, do so for their peculiar characters – their poisonous nature, their power to sting or bite, their quick flight; and these mimics are quite animate too – they’re bold, and fly about more freely. Those that mimic inanimate objects are not so bold to move about, preferring to stay still as much as possible, or move as little as possible, or move only in short outbursts. Between these two, there are exceptions, a caterpillar can sport gaudy colours and give up on ‘hiding’ because it carries enough toxins to be eaten. Similarly, an oak leaf butterfly can sport ridiculous shades of colours and dazzle, almost hypnotizing those that look – a hunter or me – and fly about freely in the canopy.

Well, what’s the deal here? Let us imagine a scenario. Imagine I’m the hunter, not the photographer. I find a yellow-red striped caterpillar and take a bite. Uh oh! It turns out to be too bitter, making me throw up and swear never to try this yellow-red striped caterpillar again. Now I find a leaf-like caterpillar and take a bite. Voila! It turns out to be too good to eat, but they’re so well camouflaged – how and where I’ll find them is up to chance! There’s loss and gain in both these instances, the yellow-red striped sacrificed its life to ensure the others of its kind survived; the leaf-like caterpillar died an unfortunate death, but it knows that its odds of survival are better than that of the birds that don’t really see particularly well in the green.

The leaf and leaf-dwellers, a Baronet caterpilar, a Leafy katydid, a Narrow-mouth frog, and a grasshopper.

In the end, it is a race to survive, a tug of war, a dance of life and death. Alright, that’s that. What is the second most common features of a leaf? The veins, the spots, the blotches and blemishes, right? Some look exactly like the midriff of a leaf even taking the position there when at rest, like this Baronet butterfly caterpillar, or some try to be a leaf, such as this leafy katydid (Phyllomimus sp.).

Sometimes, I may just be perceiving things that do not really exist. While sauntering, I found two of these brown critters on green leaves with some blotches and blemishes – a narrow mouth frog (Microhyla ornata) and a grasshopper (Catantops sp.), both positioning themselves naturally – I did not place them there – on the leaf, just sitting, thinking they’re extremely well hidden from plain view as I sauntered by.

Trunks, branches, and sticks; a Huntsman spider, a Bush cricket, a Stick insect, and a semi-looper caterpillar.

Other than leaves, its mostly just tree trunks, branches, and the slender stems that take up a large volume of space. In fact, in a well-wooded forest, tree trunks make up the largest surface area than the actual surface on the ground. Quite naturally, this space is taken up, too. Specifically, it has been opportunistically taken up by those who want to look like a part of a tree. Some of the most common you may find anywhere in an Indian forest are spiders – the likes of Heteropoda sp. (shown here), but also two-tailed spiders (Hersilidae) where the whole family specialises on tree trunks and other vertical surfaces. The bush crickets (Sathrophylla sp.), cousins of the leafy katydids, are specialists of branches, where they remain so well pressed against the surface that they don’t even form shadows. The stems pose an excellent opportunity to go unnoticed – the stick insect is true to its name, as this fellow lady (quite possibly Carausius morosus) shows off proudly perched atop a broad leaf, proud of her excellent camouflage. I even saw a tiny ballooning spider land on her and make itself comfortable under the stick insect’s abdomen. The most difficult to spot are the caterpillars that mimic stems – mostly loopers and semi-loopers, trying to imitate a stem down to the very grooves and blemishes.

Now we must note here that when it comes to bark-residents, not all are trying to consume it. These bark-residents do it for two reasons, to hunt other bark-residents, and to hide from the bark-hunters. I call it the bark ecosystem; it is unique to each and every forest!

There’s this question that has been bothering me for a while: in your saunters, how many times do you notice poop? Bird droppings, to be exact? If like me you barely notice imperfect leaves, like me you almost never notice bird poop. But after the features of the leaves, it is bird poop that is most common on a leaf surface. Something, somewhere, perceived this too.

Bird droppings on leaves.

Moreover, they also noticed that barely anything, if ever, notices bird poop. Imagine having perceived bird dropping as a potential means to get away from being eaten. Certainly, it has seemed to work! There are several species of spiders that intentionally appear like bird droppings – or it is purely our imaginations. Bird dropping spiders in the genus Cyrtarachne (shown here) and Pasilobus indeed look like poop on a leaf. There are several adult moths and early instars of some Papilo butterflies that look impressively – for the lack of a better term – like poop. One particular moth has taken this to a whole new level. Macrocilix maia, a not-so-uncommon moth of South Asia, portrays what looks like two flies on each forewing feeding on a bird dropping pattern on the hindwings. Many Muscoid flies are known to feed on bird droppings. To be able to mimic a quick-to-fly insect, not one but two of them, on bird poop, is a whole different-level of imagination. What it must have taken to perceive this as a mechanism to prevent detection is something I cannot comprehend. Perhaps it is simpler than we imagine, but do note that not many insects mimic flies – unlike organisms like wasps, bees, and ants – among the most abundant of biting and stinging insects out there. To pretend to be poop, of course, is better if you want to avoid detection.

I’ve been using two terms quite openly and interchangeably, ‘imagination’ and ‘perception’ but there’s a fine line between the two. Imagination is when you think of something, irrespective of whether it is in front of you or not. For example, I imagined a rolled-up leaf to be a caterpillar.

Perception is when you feel something different about something which you are experiencing. For example, I see a caterpillar for a rolled-up leaf.

Both are born from our previous experiences. For instance, I imagined a rolled-up leaf to be a caterpillar because I have seen a caterpillar that looks like a rolled-up leaf. And, I perceived a caterpillar for a rolled-up leaf because I have seen a caterpillar that looks like a rolled-up leaf. In other words, as observers, it is a lot about having a ‘trained’ and an ‘untrained’ eye. Simply put, a trained eye knows what it sees, and can shuffle between imagination and perception. An untrained eye hasn’t experienced it to imagine before it starts to perceive. Luckily, we’re both trained and untrained because our experiences make us imagine and perceive things all the time.

We’ve seldom, if ever, looked at leaves as closely as a plant taxonomist (they’re a rare but fantastic breed). So, assuming that we’re all somewhere in-between the imagination and perception scale, let us put it to test.

Patterns of leaves. Or is it?

I think I’ve set the tone to what we’re looking for here, hence I won’t say it out loud. There are two explanations to your answer; one, that you have already seen it hence perceived that this must be the correct answer, or two, that you’re guessing it based on your imaginations. It is not about the correct answer, it is about how quickly you can choose that answer; as a bird, you don’t have time to sit and identify what you can eat, you have to pounce upon it and gulp it down.

This is the simplest difference between a trained and an untrained eye – a trained eye has seen it before to remember it well, while an untrained eye may take some time to recognize it. Sometimes, we’re as na├»ve as an early bird.

There’s a story behind the butterfly with ridiculous shades of colours. The genus it belongs to, Kallima, means beautiful (from Latin kallimos), and the specific name, inachus, comes from Inachus, the river god of Greek mythology. Commonly, it is known as the Orange Oak Leaf, with almost all the butterflies in Kallima genus known as oak leaf. It is not known when and why the name ‘oak leaf’, among other names such as the dead leaf, leafwing, and leaf butterfly, became popular. Generally, oak leaf is popularly considered for all Kallima species. No reference of it is made in Blandford’s 1905 book introducing India’s butterflies to the world.

To come back to the ‘imagination’ versus ‘perception’ discussion, someone, somewhere, imagined this butterfly to look like an oak leaf. I then went on to Google to look at some oak leaves, and none of them from Europe looked like the name-sake butterfly. The oak tree (Quercus sp.) is diverse, with most leaves sinuate (with the leaf showing several lobes around the edges) or dentate (like the edge of a saw) – definitely not what the oak leaf butterfly looks like. Oak is a mostly temperate tree with about 16 species found in the Himalaya – most showing leaves very much unlike the oak leaf butterfly.

Quercus pachyphylla and Kallima inachus, or, Oak leaves.
Left image belongs to plantillustrations.org.

Finally, thanks to Google, I found one that not only matched with how our tropical butterfly looks, but is also found in India; Quercus pachyphylla (syn. Lithocarpus pachyphyllus; pachy is Latin for thick, phylla is leaf), a rather uncommon tree restricted to the north-eastern India. Was it this tree that inspired someone to call it so, or did it just sound amusingly pleasing to name a butterfly as such? We’d probably never know, but the name is here to stay, so we might as well figure out why. Well, now we come to the next part of this discovery: For someone with limited knowledge of oak trees, I sure perceived the leaf of an oak to look like this butterfly, but that is certainly not the norm with leaves of most oak species. So, while the question remains why the name ‘oak leaf’, we can only speculate that it was probably someone’s imagination, or someone who had perceived this butterfly to look like the leaf of a particular oak species, such as Q. pachyphylla. I’m betting on the former.

So far we looked at imitations of inanimate objects with an objective to stay hidden from plain sight. Sometimes, staying still requires some additional measures as a double-check. If you’re still with me, consider this too. How do you perceive two sets of eyes intently staring at you? A little unnerving? How do you perceive a sudden flash of two eyes while you’re in a dense forest undergrowth? A little threatening?

Several species of insects have eyes that are tiny, unnoticeable, and often only for the purpose of distinguishing light from shadows. Curiously, they know what a bigger pair of eyes can do: it can unnerve you, it can threaten you, you who is after their life. And they did just that, they got themselves a set of false eyes on a part of their body they could proudly display, their wings, their backs. That took some million years of permutations of combinations too. These false eyes, or ocellus, are of various shapes, some carry a glint, some look up, some look forward, some are blank pits – windows to look into the depth of your souls.

The moods of ocellus - hypnotizing, stalking, goofy, and zen.

Caterpillars flaunt it, adult butterflies and moths flaunt it – it is a way to show not just ‘I’m here’ but ‘I’m watching you’ or ‘I’ve seen you’ – a strategy that generally startles hunters. It is true that it doesn’t work every time, but if it didn’t work at all, it wouldn’t have been such a common strategy to make someone look away, even some fishes don ocellus markings. Curiously, this strategy is applied by another flawless hunter that mimics dry grass.

The egg-like ocellus of the Danaid Eggfly and her mimic.

In addition to the enchanting – or scary – real eyes, cats have ocellus, too. Exactly like a butterfly’s ocellus. Almost all cats have the back-side of the outer ear, pinna, differently coloured than the rest of the body. Generally, it is half-black with the other half a lighter shade. It is most pronounced only in some cat species, and is particularly well ocular-like in tigers. If a tiger is sitting in the grass, you might not make out its shape, but if it is faced away from you, the ocellus on its pinna stands out. That’s how my friends and I spotted this tiger lazing in the grass one evening.

There are many reasons, all plausible, for why an apex predator such as a tiger needs ocellus. It is so that its cubs can spot one another and the mother easily. It is so that those approaching from behind the tiger are made aware of what lies in front of them. Or is a tiger trying to mimic a butterfly’s wings, like this eggfly? That’s preposterous, you might mutter.

The young forest of Kanha Jungle Lodge, where I sauntered.

I see a Tickell’s Blue Flycatcher perched in the middle canopy, singing on top of his voice. His deep-evening-sky-blue colour contrasts against his sunset-yellow breast. The whole bird stands out from the blue-green-browns of the forest. I sip my coffee listening to and watching this blue bird. He is letting it all out. Somewhere, a female Tickell’s Blue Flycatcher is perched, quite possibly looking at this handsome bird perform. She’s a tad duller in colour, slightly blue-green-brown than her counterpart. Quite possibly hidden from my eyesight, in spite of being in plain view. Being a leaf.

Comments

  1. A very insightful depictions!! The black/white effect was brilliant way to explain a hunter's vision!! Looking forward to more such interesting imaginations/perception :)

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