Archive for the ‘crabs’ category

Why you (may) dislike Arthropods and I don’t!

4 January 2011

I’m absolutely sure that most of you who see the image above will cringe, shudder or grimace.  These fearsome  (to some) creatures are Arthropods and they are by far the most numerous set of creatures on Earth. Insects, scorpions, crabs, centipedes and shrimp and many others comprise this group. All these have jointed legs – hence their name.

I am talking about a form of “racism” in our human culture – our attitudes to species other than our own.


The wonderful diversity of Arthropods (Image:User xvasquez on Wikimedia Commons, Public domain)

Mammals? Like us, they are warm (blooded), furry, and some arey cute. Birds? Interesting creatures that fly  (I wish I could do that) and listen to how sweetly this one trills. Fish? Only good for a meal! Reptiles? Definitely on the other side of midnight along with arthropods.

The origin of our dissonance with the environment is Mankind’s inherently false belief that we are separate from Nature. Since we are the only species that has been able to think about the future and the environment to meet our future needs, we consider ourselves above and beyond it. Our scientific and technological progress, instead of increasing our knowledge and giving us an enlightened view of things, has made us prideful of our ability to range across our realm from the Moon to the depths of the Ocean, to extract our materials from living and non-living things and to fashion with them things which help us create strange and wondrous things, to increase our population way beyond the natural capacity of the Earth and to mine the natural world for even more.

Even though from time to time, Nature sends us reminders that we are finite and an infinitesimal part, but nevertheless a part in the grand scheme of things, in our pride, like the Gods, we see ourselves apart.

Yet, a barf of ash from a once dormant volcano in Iceland has halted all the air traffic over most parts of Europe. And there is nothing our technology can do to prevent this.

Refusing to believe the evidence of our senses, we lumber on ignorantly, confident in our belief that we, as a species, are superior. That Nature is there at our bid and call for the express purpose of our convenience. That we have conquered Nature. That all its creatures exist at our pleasure. That Man is the Measure of all things.

This attitude, surely an express highway to self-destruction, is the reason that we like some creatures and hate or ignore all the rest.

Why do we dislike arthropods so much? The answer to this must surely lie in childhood.

As an infant, we may have had an experience in which an insect or other creature walked on us, tasted horrible or flew into our face. Our caring elders would have hurried us away from them or warned us against them. Should we have been unfortunate enough to have been stung or bitten by one, it would imprint on our tender psyche forever. As time passes, the looks and the activities of these creatures reinforce the negative images about them. We feel that since they are small, they could fly onto us even perhaps into one of our orifices. Their legs, antenna and spikes on the body remind us of thorns.  Their numerous legs make us imagine how it will feel crawling on our hands!  In the absence of anything positive feedback about creepy-crawlies, we develop an abhorrence of ‘bugs’.

Our belief is now firm and irrational. The “mythos” has overtaken our “logos”. Blind belief instilled as fears as a child supercede rational understanding gained as an adult. It will take a conscious act for us to detach the negative feelings that these creatures engender in us. Since we are Man with a developed brain and a conscious mind, we can do so.

As I did many years ago.

In the words of Dr Steve Kellert (read more here) :

Dr. James Hillman, in a classic essay, “Why we hate Bugs?,” provides some psychological insight regarding why these differences between humans and invertebrate scale and behavior might result in feelings of alienation and aversion. Reviewing a long history of prejudicial attitudes and antagonistic behavior of humans toward arthropods, Hillman remarks, “what we call the progress of Western civilization from the ant’s eye level is but the forward stride of the great exterminator.” Hillman suggests four reasons for human psychological aversion and antipathy toward invertebrates, mainly insects and spiders, found among most people in Western society.

First, he emphasizes the “multiplicity” of the invertebrate world, which he suggests threatens our fondly cherished human notions of individuality and independence. He suggests the idea of a bee hive that can include 50,000 individuals, or a large ant colony of half million ants, or an acre of soil with 65 million insects, or beetle species numbering more than one million, represents a fundamental challenge to our sense of personal integrity and individual oneness. He remarks: “Imagining insects numerically threatens the individualized fantasy of a unique and unitary human being. Their very numbers indicate insignificance of us as individuals.”

A second basis for anxiety and aversion, Hillman refers to as the “monstrosity” of most invertebrates from a human perspective. In this regard, he notes the tendency of most people to associate invertebrates, especially insects and spiders, with metaphors of madness and mindlessness. The human presumption, as noted, is to assume invertebrates as incapable of feelings and rationale reflection, and many common terms of insanity employ insect names, while images of madness often involve visions of insects and other arthropods. As Hillman suggests: “Bug-eyed, spidery, worm, roach, blood sucker, louse, going buggy, locked-up in the bughouse – these are all terms of contempt supposedly characterizing inhuman traits… To become an insect is to become a mindless creature without the warm blood of feeling.” A third explanation Hillman offers for dislike of invertebrates originates in their radical “autonomy” from human will and control. A particularly disturbing aspect of their independence or indifference to human hegemony is the willingness to invade human space in unexpected and uninvited fashions.

Finally, Hillman suggests a disturbing element about invertebrates for most humans stems from the quality of “mystery” surrounding them. As noted, invertebrates represent radically different behavioral and morphological strategies in the struggle for survival which for most humans provokes considerable uncertainty, confusion, and a sense of “otherworldliness.” This sense of mystery can be a basis of curiosity, interest, and even wonder, although the more typical reaction is one of disdain and fear of the unknown. For most humans, invertebrates are largely unfathomable and alien.

Hillman suggests conservation of wildlife, especially invertebrates, will necessitate a far greater understanding of why we react with hostile and negative feelings toward various creatures, particularly insects and spiders. To find our commonality with the animal world in its widest diversity, “we must start (with animals) not in their splendor – the horned stag, the yellow lion and the great bear, or even old faithful `spot’ – but with those we fear the worse – the bugs.”

The above paragraph gives many reasons on a psychological level why people regard arthropods as abhorrent. In the same way, people fear snakes and are blind to the amazing abilities that the snakes have evolved despite having no limbs of any kind.

Arthropods are such wonderful creatures in so many ways, I find it hard to select which facts to tell you about them.

Let me start with camouflage.

Insects (and other arthropods) are nutritious food. They contain valuable protein and reserves of fat in some cases. All kinds of animals eat them – birds, mammals, reptiles, fish, amphibians. Even man eats them – this is called entomophagy.

As an aside, no matter how strict a vegetarian you are, you eat insects every day. Here‘s why?

In order to avoid being eaten insects adopt a variety of strategies, one of which is camouflage. Camouflage is a method of crypsis—avoidance of observation—that allows an otherwise visible organism or object to remain indiscernible from the surrounding environment through deception. Examples include a tiger‘s stripes and the battledress of a modern soldier. The theory of camouflage covers the various strategies which are used to achieve this effect. (Courtesy:Wikipedia)

A Leaf Insect from Wyanaad, India. Here, the camouflage is used defensively, to escape being eaten. (Image:Sandilya Theuerkauf on Wikimedia Commons, CC-BY-SA-2.5)

 

A stick insect - shades of Tolkien's ents! (Image:Fir0002 on Wikimedia Commons, CC-BY-SA-3.0)

A challenge - find the pink soft coral crab hiding in the soft coral of the East Timor Sea. (Image:User Nick Hobgood on Wikimedia Commons, CC-BY-SA-3.0.)

Did not succeed? Okay try again after seeing another photo of this amazing crab – Pink Soft Coral Crab, Hoplophrys oatesii, placed after this one of camouflage used not to hide from predators but to become one! An evolutionary arms race!

 

Camouflage for predation - A perfectly camouflaged jumping spider captures a solitary wasp. (Image:Muhammed Mahdi Karim on Wikimedia Commons, GFDL 1.2)

 

The coral crab now visible on Pink Coral. Image:User Nick Hobgood on Wikimedia Commons, CC-BY-SA-3.0.)

Camouflage for predation - A crab spider can change its colour depending on the flower it chooses to live in to catch its prey, in this case a wasp. (Image: Olaf Leillinger on Wikimedia Commons, CC-BY-SA-2.0-DE)

The two forms of the Peppered Moth. Earlier the melanistic (dark) form was uncommon while the peppered form was predominant. The increasing soot on trees in England due to the industrial revolution changed the evolutionary dynamics and today the melanistic form predominates as the peppered form has been selected out due to high visibility on blackened bark of trees.

The Peppered Moth Biston betularia (Linnaeus, 1758) is a text book case for evolution. Changes in environment reduced the viability of one morph and increased that of the other. The insect evolved accordingly to have a predominantly larger population of darker morphs.  This graphic of a related Geometer Moth shows how effective camouflage can become a hindrance once the environment changes. Drag the mouse over the background to see it disappear and show just the moth. The moth is perfectly camouflaged on the tree bark but if the background changes, as in the case when you dragged the mouse, the moth becomes prominent and a target instead.

Want to see more?

Insects have many facets similar to the trades of humans.

If you are an underwater diver, you would be interested in the Diving bell spider.

The diving bell spider or water spider, Argyroneta aquatica, is a spider which lives entirely under water, even though it could survive on land. (Image:Norbert Schuller Baupi on Wikimedia Commons, CC-BY-SA-3.0)

If you keep cows or sheep, the ant also belongs to your trade guild . Many species of ants “herd” aphids for honeydew. The ants in turn keep predators away and will move the aphids around to better feeding locations. Upon migrating to a new area, many colonies will take new aphids with them, to ensure that they have a supply of honeydew in the new area.

 

An ant guards its aphids. (Image:ViaMoi on Flickr/Wikimedia Commons, CC-BY-SA-2.0)

 

Ants feeding on the honeydew of the aphids. Notethe dewdrop exuding from the rear of the aphid. (User:jmalik on Wikipedia, Creative Commons 3.0)

If you are a soldier like me, you will be interested in the army ant. The name army ant (or legionary ant or “Marabunta“) is applied to over 200 ant species, in different lineages, due to their aggressive predatory foraging groups, known as “raids”, in which huge numbers of ants forage simultaneously over a certain area, attacking prey en masse.

Another shared feature is that, unlike most ant species, army ants do not construct permanent nests, an army ant colony moves almost incessantly over the time it exists. All species are members of the true ant family, Formicidae, but there are several groups that have independently evolved the same basic behavioral and ecological syndrome. This syndrome is often referred to as “legionary behavior”, and is an example of convergent evolution. (courtesy:Wikipedia)

 

Some safari ant soldiers on the Chogoria of Mount Kenya make a tunnel to provide a safe route for the workers. (Image:Mehmet Karatay on Wikimedia Commons, CC-BY-SA 3.0)

The amazing number of examples of insects and other arthropods which can illustrate any phenomenon or theme that you want is mind-boggling. Like the scope for thematic collectors in a world of 530,000 or so postage stamps, the many hundreds of thousands of arthropods are more than enough to satisfy the curiousity of any person.

Perhaps the following links will help you to become interested in arthropods and nature :

For children:

For the more enthusiastic:

As a closing quote, let us see another view of the “Age of Man” :

Don’t accept the chauvinistic tradition that labels our era the age of mammals. This is the age of arthropods. They outnumber us by any criterion – by species, by individuals, by prospects for evolutionary continuation.

Stephen Jay Gould, 1988

It is time to shed our inhibitions and accept the notion that these too are God’s creatures and deserve to live on Earth as much you do.

NOTICE : This post has already been published as a Guest Post on Gingerchai.com over here . Special thanks to Lakshmi Rajan for giving a platform for my contrarian views.

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Epic splendour

13 February 2010

The nature writing of James Michener

One does not often associate James Michener with nature-writing.  He writes epics, sometimes likened to fictional documentaries, with wide strokes on broad canvases. Yet in most of his epic stories,   it is difficult not to find a a chapter or more about the land, its formation, the animals, the plants and the people who live amongst them.

Like another of my favourite authors, Louis L’Amour, Michener is one with the panorama that he writes about, be it desolate and strange, or familiar and unremarkable.

A pine-clad valley ringed with buttes and a snow-clad mountain, King's Peak above which white clouds cover most of a rich blue sky.

King's Peak seen across Henry's Fork basin. This scenic vista, the essence of his books about continental USA, corresponds to the broad and diverse subject matter of Michener's epics, considered by some to be fictional documentaries. (Image : Hyram K. Wright. GFDL)

Somerset Maugham once stated about writing that :

The best style is the style you don’t notice.

So it is with Michener, he researches his biology, his geology and writes.  When he does so, he transports us back into time. In our mind, a movie runs, initiated by his simple, eloquent yet powerful style.

Drawing of a large heard of bison and other animals with outline in charcoal and yellow/brown colours presumably by use of ochre and haematite dies. This is a prehistoric work of art found in Altamira cave in Spain.

Prehistoric Bison painted by paleolithic man in Altamira cave (Spain). (Image: Reconstruction by Emille de Cartailhac, 1906. Public domain).

Take for example this passage from “Portrait of Rufous” from his novel ‘Centennial‘ :

..the wolves that hung about the edges of a herd, hoping for a bit of luck, spotted the little calf.  They had a good chance of picking him off, since the older bull was endeavouring to kick him to one side. So they closed in on the running pair, trying to insert themselves between the baby bull and the mature one.

They failed. Once Rufous recognised their strategy, he became a changed animal. It was his responsibility to protect calves, no matter how bothersome, no matter how distant the retreating heard. Accordingly he scanned the terrain as he ran and spotted a small embankment that may provide protection.

Twisting his head abruptly to the right, he headed for the rocky bank. As if the young calf had been physically attached to him, he turned at the same time and the two galloped to the refuge. There Rufous turned to confront his enemies, keeping the calf beside him and well protected by his large flank.

The wolves closed in, eleven of them, but they were powerless against his horns and massive head, nor could they slip behind him to attack his tendons because he kept his rear tight against the rock. If he had not been hampered by this irritating calf, he could have been beaten back the wolves and returned to the herd, but with that encumbrance, he could do no more than protect himself.

He did manage one other defense.  He bellowed several times – the low guttural cry seemed to roll vainly across the vast pririe.  But he was heard.  The bison having outrun their fright, had stopped and were aimlessly milling around when the master fighter of the herd to whch Rufous belonged, the large black bull, heard the cry of distress and doubled back to investigate. With him came the bull with the slanting left horn, and the closer they approached the intermittent bellow, the faster they ran.

A brightly coloured bison with head down charging to the left. Coloured in rufous, black,  burnt umber,  wheat and white. Colour names from 'List of colours' in Wikipedia where each colour is shown with associated name.

Rufous - painted by a paleolithic artist half a world away. (Image: Public domain photograph.)

Geological happenings such as the formation of the land masses, oceans, archipelagos, glaciers, mountain ranges, great lakes and valleys are all grist for the mill to Michener. A moving hot spot through the Earth’s crust left islands strewn like a string of pearls.  Such things fascinated Michener, for in two books – Hawaii and Centennial – he has included a chapter on how the land was formed, the violent volcanic upheavals in the Pacific in the case of the former and the titanic pushing of the continental plates in continental North America in the case of the latter.  Not only does Michener write on such seemingly dry, dusty topics, he in fact waxes poetically about them.

A sunset scene of an ocean with a distant coastline to the right. The blood-red and black colours of the sunset on the Bering Sea are analogous to the powerful tectonic forces and magma movements which created land in the midst of the Pacific Ocean, millions of years ago.

Black and blood-red sunset reflected in the dark ocean waters of the Bering Strait remind one that islands in the Pacific were borne of fire and lava millions of years ago. (Image: NOAA, public domain).

See how Michener writes about the very first super-ocean in the chapter “From the boundless deep” in Hawaii :

“Millions upon millions of years ago, when the continents were already formed and the principal features of the earth had been fixed, there was, then as now, one aspect of the world that dwarfed all others. It was a mighty ocean, lying to the east of the largest continent, a restless, ever-changing, gigantic body of water that would later be described as pacific.

Over its brooding surface immense winds swept back and forth, whipping the waters into towering waves that crashed down upon the world’s seacoasts, tearing away rocks and eroding the land. In its dark bosom, strange life was beginning to form, minute at first, then gradually of a structure now lost even to memory. Upon its farthest reaches birds with enormous wings came to rest, and then flew on.

Agitated by a moon stronger then than now, immense tides ripped across this tremendous ocean, keeping it in a state of torment. Since no great amounts of sand had yet been created, the waters where they reached shore were universally dark, black as night. Scores of millions of years before man rose from the shores of the ocean to perceive its grandeur and to venture forth upon its turbulent waves, this eternal sea existed, larger than any other of the earth’s features, more enormous than the sister oceans combined, wild terrifying in its immensity and imperative in its universal role….

…then one day millions of years ago, a rupture developed in the rocky bed of the ocean. It occurred near the middle of the sea, a bit closer to what would later become the western United States than to the shores of eastern Asia. Some great fracture of the earth’s basic structure had occurred and from it began to ooze a white-hot liquid rock. As it escaped from its internal prison and came into contact with the ocean’s wet and heavy body, the rock instantly exploded, sending aloft through the nineteen thousand feet of ocean that had pressed down upon it columns of released steam.”

In most books, Michener chooses one or more animals, their stories to tell as part of the textual mural. In ‘Chesapeake’, he writes of Onk-or, the wild goose, and of Jimmy, the Blue Crab, which formed part of the delicious New England fare and on whose shell, several fortunes rested. In Texas, he writes of armadilloes whose determined predations left a hapless Texas town helplessly unable to protect their lawns. In Alaska, it is the story of Nerka, the salmon.

A mammoth stridin forth towards and to the left of the observer holding aloft its brace of large curved tusks. The mammoth walks along a shallow draw outlind by forest on undulating slopeds behind it. On the right side of the image, to the right and behind the mammoth, part of its herd can be seen with three adults and two calves proceeding from left to right.

An American Mastodon, the most recent of the genus of extinct probiscideans. While mastodons had a size and appearance similar to elephants and mammoths, they were not particularly closely related. (Image: 1897 portrait by Charles Knight. Public domain.)

In Alaska, we also get to meet two fascinating prehistoric pachyderms – the Mastodon and the Woolly Mammoth.

Whats the difference between a Mastodon and a Woolly Mammoth?  Mastodons lived  from 40 million years ago (mya) to about 10,000 BCE. They were browsers – they fed on leaves, soft shoots, or fruits of high growing, generally woody, plants such as shrubs. They had no hair.

Michener writes in ‘Mastodon’ :

Nowhere else could the subtle relationships be intimately observed. Ice high, oceans low. Bridge open, passageway closed. The ponderous Mastodon lumbering toward North America, the delicate horse moving toward Asia. Mastodon lurching toward inescapable extinction. The horse galloping toward an enlarged life in France and Arabia. Alaska, its extremities girt in ice, served as a way station for all the travelers,    regardless of the direction in which they headed. its broad valleys that were free of ice and its invigorating climate provided a hospitable resting place.

On the other hand, Mammoths had a thick layer of shaggy hair and were  grazers (grass eaters). They  lived from 4.8 million to 4,500 years ago. In Alaska, they existed at different points in time, when the climate was different.

Both these animals were wiped out as part of the great Pleistocene megafauna extinction.

A herd of Wolly Mammoths cross the tundra watched by other animals - cave lions, horses and a woolly rhinoceros. Patches of snow cover the ground. In other places grass shows up. A few trees are also seen. The weather appears overcast with a few clouds. on the horizon.

Matriarch leads her herd across the Alaskan tundra. (Image:Mauricio Anton, License CC - A - 2.5 generic.)

About woolly mammoth, Michener writes:

One day late in winter, twenty-nine thousand years ago, Matriarch, a mammoth grandmother, forty four years old and beginning to show her age, led the little herd of six for which she was responsible down a softly rolling meadow to the banks of a great river later to be known as the Yukon. Lifting her trunk high to sniff the warming air and signaling the others to follow, she entered a grove of willow herbs that lined the river, and when the others had taken their place besides her, she indicated that they might begin feeding on the sprouting tips of willow branches. They did so with delight because they had subsisted on meager rations during the previous winter, and as they gorged, Matriarch gave grunts of encouragement.

It is in the novel Centennial that we see Michener provide a bewildering array of animal stories in a chapter titled ‘The Inhabitants’.

Let the word ‘chapter’ not fool you for Michener provides a complete set of animal stories discussing the appearance and interaction of the earliest creatures. He starts from the dinosaur “Diplodocus” to go on to the fore-runners of the modern horse, the prehistoric bison, the giant beaver, the rattlesnake and more.

A blue crab resting on mud with its arms outstretched towards the right and below. Its orange and blue markings are prominent.

Jimmy, the blue crab of Chesapeake Bay. (Image: NOAA - public domain.)

Michener is careful about his research. An account of his preparation for the novel ‘Covenant’ can be found here. In “Jimmy the crab”, one meets a Blue crab facing the challenge of extensive siltation and excessive fresh water. The story tells of how a hurricane created such a problem for the crab, the crabs efforts to cope and their eventual death due to pollution. It is told simply, the secrets of crab biology informed in a most matter-of-fact way and harsh reality not denied.

Michener loves his animals. His writings bear no sign of anthropomorphism except in the choice of the subjects themselves. He writes of the love he felt for a pet hyena in Spain where he wrestles and plays with a creature whose robust jaws could have crushed a limb or his face but which never did so while holding them gently within its formidable maw. He also tells of a fellow-feeling that he felt for a particular grizzled old bison when he spent time studying a bison herd. He decided to make this bison and the hyena the protagonists of two stories.

To find Michener’s nature stories, one does not need to trawl through his literature, which of course is the best way to read him and understand how he viewed nature in its context. The stories have been collected and during his lifetime itself issued as “The Creatures of the Kingdom”. The book has a foreword by Michener himself and tells of his attitude to nature. Michener writes:

I cannot think of myself as exceptional in any respect. I know that man could never have survived the violent volcanoic upheavals in the Pacific Ocean that created the glorious chain of Hawaiin islands. The first tenants of the newly born Rocky Mountains surely did not walk upright. My kind has lived here on Earth only a few million years; the dinosaurs thrived for a hundred million. And I am not homocentric enough to think that man embodies all that is best in the animal kingdom, in which he plays a dominant path. He cannot slither along his belly like a snake or use his nose to feed himself the way an elephant can. He has not the incredible hearing system of a bat, the sense of smell of a bloodhound, or the capacity to survive underwater like a slug. He cannot cast off his aging skin like a crab or stand motionless for hours on one foot like a blue heron. Man is a wonderful creature, majestic in his mental capabilities, but in many other respects he is either limited or downright deficient.

A postage stamp with Michener's face facing us smiling. Wearing bUsh shirt, spectacles and a  flowery garland.

Great Americans series - 59 cents James Michener 2008 issue

So what is Michener’s reason for including such powerful nature writing into his epics ?

One reason could be that Michener wants to portray a truth he himself has expounded…

If man assesses himself honestly when he compares himself with other animals, he can avoid getting a swollen head…

That then, in my humble opinion,  is Michener’s ultimate purpose of writing about nature – to portray man as just one facet in a long timescape. An important cog admittedly in the machinery of the world today, but a cog nevertheless.

Image credits: All images have a free license and can be found on Wikimedia Commons. Go to the source page with full details of attribution and licensing by clicking on the image. Except for the stamp image which is used here under fair use.

Crabs

20 January 2009

(An extract from ‘A Naturalist on the Prowl’ by E.H. Aitken)

A naturalist on the prowl!

Prowling on the seashore one evening, I espied another prowler, and he espied me, and avoided me as the burglar avoids the policeman. He did not run away, but just deflected his course a little, took advantage of a dip in the sandy beach, got behind a growth of screw pines and was not there. It was getting too dark to see clearly, but by these tactics I knew that he was a jackal. He had come down in the hope of catching a few crabs for his supper. Scarcely had he got himself away when, with a shrill squeak and a scrambling rush, a fat musk rat escaped from my foot into a heap of stones. What was it doing there? Hunting for crabs. Now there is something very revolting in the thought that crabs are liable to be killed and eaten by foul jackals and disgusting musk rats. The crabs are a peculiarly interesting people, like the ancient inhabitants of Mexico, unique and not to be ranked with the other tribes of the earth.

anotp-jackal-on-the-shore

Professor Owen holds that the hand of man suffices to separate him from all other animals almost as widely as any two of them differ from each other. “The consequences,” he says, “of the liberation of one pair of limbs from all service in station and progression are greater, and involve a superior number and quality of powers, than those resulting from the change of an ungulate into an unguiculate condition of limb.” Think me not a mocker if I suggest that the crab shares this endowment with man, and perhaps that is the reason why he seems to stand apart from all other creatures that are clothed with shells. By pedigree the crab, I admit, is but a prawn which has curled its tail under its stomach and taken to walking; but no one who has lived much among crabs and associated with them, so to speak, can lump them with prawns and other shell-fish good for curry. A crab is not like a lower animal. He does not seem to work by instinct. All his avocations are carried on as if he had fixed principles, and his whole behaviour is so deliberate and decorous that you feel almost sure, if you could get a proper introduction to him, he would shake hands with you.

At times I have thought I detected a broad grin on the face of an old crab, but this may be fancy. I incline to the idea, however, that he has a sense of humour. He is courageous too-not foolhardy, but wisely valiant, and marvellously industrious. Watch him as he repairs his house flooded by the tide. Cautiously he appears at the door with a great ball of sand in his arms, and erecting his eyes to see if any enemy is near, advances a few paces, lays his burden down and returns to dig. Again he appears and puts a second ball besides the first, and so on till there is a long even row of them. A second row is then laid alongside the first, then a third, and a fourth; then a passage is left, after which a few rows more are laid down. So rapidly is the work done that the tide has scarcely retired when the whole beach is chequered with flowerlike patterns radiating from a thousand holes. These are the work of infant crabs mostly, for as they grow older they venture to retire further from low water mark, where the sand is dry and will not hold together in balls. Then they bring it up in armfuls and toss it to a distance. But, old or young, their houses are swamped and obliterated twice in every twenty-four hours, and twice dug out again; from which you may judge what a life of labour the sand crab lives.

The sand crabs reach almost upto the Screw pine (Pandanus) zone.

The sand crabs reach almost upto the Screw pine (Pandanus) zone.

The sand crab...

The sand crab...

...and his labour.

...and his labour.

Plover patrol! Watch out, sand crabs!

Plover patrol (foreground)! Watch out, little sand crabs!

He is, I think, the noblest of his race. Living on the open champaign of the white sea-shore, he learns to trust for safety to the keenness of his sight and the fleetness of his limbs. Each eye is a miniature watch-tower, or observatory, and his legs span seven times the length of his body. When he runs he seems to be on wheels: you can fancy you hear them whirr. But, keen as is his sight and amazing as is his speed, he more than needs it all; for, alas! he is very tasty and all the world knows it. In his early days the sandpipers and shore birds, nay, the very crows and preh pudor! my turkey patrol the water’s edge, and he scarcely dares to show his face by daylight. Then, as he grows beyond the fear of petty enemies, he comes within the ken of greater ones. The kite, sailing high overhead, swoops like a thunderbolt and carries him off. The great kingfisher, concealed in an overhanging bough, watches its opportunity, and when he has wandered far from his hole, darts upon him and scoops him up in its long beak. The kestrel hawks him, dogs hunt him in sheer wantonness, jackals hunt him to eat him, owls lie in wait for him, and when he takes refuge in the water, an army of sharks and rays is ready for him. And man closes the list.

“These wild eyes that watch the wave
In roarings by the coral reef’

are watching mostly for crabs. He is drawn from his hole with hooks, dug out with shovels, caught in traps, netted with nets, and even in the darkness of night distracted with the sudden glare of flambeaux and knocked over with sticks.

Man - arch-enemy and predator no 1.

Man - arch-enemy and predator no 1. The crabs in the basket are Three-spotted Crabs (Portunus sanguinolentus), a swimming crab. The crabs in the basket were caught at sea by local fishermen using nets and were at Harne beach waiting to be sold. (Identification - 'Marine Life in India' by BF Chapgar.)

Many are the ways in which the race of crabs have sought to shun their thousand foes, some by watchfulness and wisdom, or cunning and skill, some along paths of degeneracy and shame. In the aeons long gone by, it seems, there lived a craven crab who condescended to seek safety by thrusting his hinder end into an empty shell, and to-day his descendants are as the sand on the sea-shore for multitude, dragging their cumbrous houses about with them and thrusting out their distorted arms to pick up food, and shrinking in again at the least sign of danger. Safety they have bought with degradation, but there are moments of supreme peril even in the base life that they lead; for the crab grows and the shell does not, and it is an inexorable law of nature that, when you change your coat, you must put off the old before you put on the new. The most ludicrous sight I ever saw was two hermit crabs competing for an empty shell. Neither of them could by any means take possession without exposing his naked and deformed posteriors to the mercy of the other, and this he dared not do; so they manoeuvred and circled round that shell and made grimaces at each other till I laughed like the blue jays in Jim Baker’s yarn.

A hermit crab (Superfamily Paguroidea)

A hermit crab (Superfamily Paguroidea)

The hermit crab drawn out in full splendour!

The hermit crab drawn out in full splendour!

Others of the race have tried to win security by burying themselves in the mud at the bottom of the sea and stretching out their beggar hands for food. The hands work hard, but the stomach is starved, and in some of this family the body has dwindled into a mere appendage to a great pair of claws. Of these is the giant from Japan, whose grim skeleton, eleven feet in stretch of limb, adorns the walls of the Bombay Natural History Society. Smaller specimens are common about Bombay.

The Japanese spider-crab (Macrocheira kaempferi), largest known arthropod.

The Japanese spider-crab (Macrocheira kaempferi), largest known arthropod.

Then there are crabs which make their backs a garden and grow seaweeds and even anemones, under whose umbrageous shelter they roam about the bed of the ocean in aesthetic security.

Midway between the mud crabs and the sand crabs is one whose ingenuity and adroitness rescue it from contempt. Its hind legs are transformed into an absurd pair of shovels, and the length of its eyes is simply ridiculous. If you have patience to sit perfectly motionless for a time at some spot in Back Bay where the retreating tide has left a dead level of oozy slime, you will see a hundred of these little blueish creatures moving about and collecting some form of nourishment from the mud with their quaint and crooked claws; but move’ a hand, and presto! they are gone. In an instant they have put themselves under the mud and left nothing, except perhaps the points of their long eyes, in the air.

A Fiddler Crab.... a mere appendage to a great pair of claws.

A Fiddler Crab.... a mere appendage to a great pair of claws.

Then there is the Calling Crab, which has fostered one hand until it has grown into a veritable Roman shield, behind which the owner may shelter himself, calmly taking his food with the other. How these hold their own I cannot tell. They are not strong, nor yet swift, nor wary; but wherever the sand is soft and black, they people the shore in countless numbers. It may be that that blazing muster of gaunt, mailed hands in orange and red, ceaselessly beckoning to all the world to come, tries the courage even of a hungry crow. I am inclined to think this is the explanation of the matter, for I have often seen one of the feeblest of the mud crabs collect in dense squadrons and perform long journeys over the open shore, with nothing to protect them from wholesale slaughter unless it was the fear inspired by such an ominous mass of legs and arms.

Sally Lightfoot! The agile Red Rock Crab (Grapsus grapsus)

Sally Lightfoot! The agile Red Rock Crab (Grapsus grapsus)

Where the foaming waves dash themselves against rugged rocks and moss-clad boulders, with black fissures between, and here and there a clear pool, tenanted by anemones and limpets and a quivering, darting little fish, chafing in prison till the next tide shall come and set it free, there the sand crab is replaced by the crab of the rocks, most supple-limbed of living things. How it turns the corner of a mossy rock, as slippery as that

“plug of Irish soap
Which the girl had left on the topmost stair,”

and awaits unmoved the onset of a great wave, then resumes its meal, daintily picking off morsels of fresh moss with its hands and putting them into its mouth. A life of constant watchfulness it lives and hourly peril, as many an empty shell in the pool bears witness. Its direst enemy, I believe, is the ghastly octopus, that ocean spider, lurking in crack or crevice, with deadly feelers extended, alive to their very tips and ready for the THE SWIMMING CRAB unwary. That this gelatinous goblin should be able to master the mail-clad warrior is wonderful but true. All his armour and his defiant claws avail nothing against the soft embrace of eight long arms and the kiss of a little crooked beak.

anotp-the-swimming-crab

Though their proper home is the border line between land and water, the crabs have pushed their conquests over nature in all directions. Some swim in the open sea, their feet being flattened into paddles, and these are horribly armed with long and sharp spines for the correction of greedy fishes. They have been found in the Bay of Biscay, a hundred miles from land, and are common on the coasts of England, where they are said to kill large numbers of mackerel. Bombay fishermen often find them in their nets. Other crabs inhabit the forests, climbing trees. Of these we have one beautiful species, all purple and blue.

The tree climbing Coconut Robber (Birgus latro)

The tree climbing Coconut Robber (Birgus latro)

Others have their home in the fields, lying buried during the months of drought, and coming to life when the rain has softened the earth. They love the rain, and often have I drawn them from their holes by means of a fraudulent shower from a watering can. Slowly the poor dupe comes out to enjoy it, and when his feet show themselves at the door, you can thrust in a trowel and cut off his retreat. Then he knows he has been fooled, and backing into a corner, extends his great claws and defies the world.

Did you ever see a motherly land crab with all her children about her, leading them among the tender grass on which they feed, like a hen with her chickens, and when their little legs are weary, gathering them into her pouch and carrying them home? It is a pretty picture, and I wish I could paint in the father of the family; but the truth must be told, and I am afraid that when he meets with his offspring, he runs them down and eats them. At least I saw such a chase once. Never did crab flee as that little one fled from the chela sequentes of his dire parent. He doubled and dodged and ran again, but all in vain! He was caught and nipped in two. Then came Nemesis in the form of my dog, and the pursuer was pursued. In his flurry he lost his way, and darting into the wrong hole, all but fell into the arm~ of a bigger crab than itself. Darting out again, he was instantly crushed by a great paw.

You may ask how I know that the big crab was father of the little one. I do not know that he was; but what does it matter? He did not know he was not.

A family meal!

A family meal!

Image credits & licensing information :

  • Note. This document is published under Gnu Free Documentation License.
  • Line drawings F.C. McRae in the original print of E.H. Aitken’s ‘A naturalist on the prowl’ and are accordingly public domain.
  • Photos of screw-pines, sand crabs, plover patrol, crabs in basket – self. [Licensed under Creative Commons 3.0 with Self-attribution].
  • Remaining photos taken from Wikimedia Commons. Please search among category ‘Crabs’ for the source images originals and their exact license restrictions.

Note 2. After I had written this blog, I realised that I had bought a natural history book some time ago about creatures of the sea. I dug it up from my book box and began reading it. I was surprised – here was so much that I wanted to learn and and all the while the book was waiting patiently for me to fetch it from its place. I’m referring to  ‘Marine Life in India‘  written by B.F. Chapgar, the renowned Indian marine biologist and doyen of the BNHS. Published as recently as 2006, it is written in a very easy to read and understand style, with nice photographs, lots of small chapters each concerning a group of animals or aspect of sea life and lots and lots of line-diagrams. If this blog about crabs interested you, and you are an amateur naturalist in India who would like to learn more about this fascinating new world, don’t have second thoughts but go out and get your own copy! It costs Rs 350/- which is not costly for such a book by today’s standards.

Disclaimer. Please note I have no commercial considerations with Oxford University Press and I am not unfortunately personally acquainted with the author.