A face only a mother could love (2)…

There’s a small, wingless parasitic wasp (Methoca ichneumonides) that preys on a green-tiger larva by waiting for it to attack before dodging past the fearsome mandibles and slipping into the larva’s burrow. The beetle larva is now the victim and the wasp closes the deal by injecting paralysing venom into its prey’s soft, unprotected body. With an incredible feat of strength and persistence, the wasp drags the limp, albeit living tiger beetle larva to the bottom of its burrow where she lays a single egg on it. She then scoots off, seals the burrow and goes about looking for more tiger beetle larva to punish.

The green-tiger beetle's nemesis - the parasitic wasp , Methoca ichneumonoides (http://delta-intkey.com/britin/images/bent3291.jpg)

Here’s a clip taken from the Life in the Undergrowth showing green tiger beetle larvae catching prey in their characteristic way and a female  M. ichneumonides taking on one of these beastly, ambush predators.

If the beetle larva manages to avoid the attentions of this wasp and other predators then it will reach the point in its life where it can pupate in preparation for its brief time above ground as an adult. Like any other insect that goes through metamorphosis, the contrast between the larva and the adult tiger beetle is amazing. The adult, with it iridescent exoskeleton and bulging eyes is also a predator of small insects, like ants, but it is an active hunter that pursues its prey over the ground with bursts of six-legged sprinting and short, fast flights, eventually getting hold of its victim and dispatching them with its fearsome mandibles.

The green tiger beetle adult is quite a sight close up, what with its metallic, iridescent exoskeleton and manic behaviour - Winterton Dunes, Norfolk (Ross Piper)

The cruel mandibles of a green tiger beetle trying to find purchase on a finger - Winterton Dunes, Norfolk (Ross Piper)

A face only a mother could love (1)…

There are a lot of people who are repulsed by insects, and for good reason, as a few of them, especially the immature stages look like nameless things that have scampered out of a nightmare. Still, it’s often the case that what these rotters lack in appearance than more they make up for in sheer interest value.

Take the larva of the green tiger beetle (Cicindela campestris) as a case in point. It’s an ugly brute:

Here's a green tiger beetle larva looking a bit annoyed at being extracted from its burrow - Winterton Dunes, Norfolk (Ross Piper)

Just take a close up look at its face:

Mug-shot of a the same larva still looking a bit put-out - Winterton Dunes, Norfolk (Ross Piper)

These may be ugly, but they’re fascinating animals that spend their whole life out of sight in a burrow they excavate in sandy soil. The larva’s spends most of its time at the mouth of the burrow, wedged against the side of the tunnel using two patches of bristles and hooks towards its back end. Its tough head, like a living lid, plugs the mouth of the burrow perfectly. Poised, ready to strike, the larva waits for unsuspecting prey to blunder over its lid-like head. The larva strikes in the blink of an eye, lunging from the safety of its burrow to grab any small insect that wanders within range. With its dinner impaled on its enormous mandibles, the larva slinks to the lower reaches of it burrow to tuck in.

These raised patches of bristles are how the larva keeps itself fixed in the same position at the mouth of the burrow for long periods of time

It’s normal to find small colonies of these larvae in areas of suitable habitat, so any small insect that accidentally wanders into these miniature killing fields will have to run the gauntlet of several, hungry tiger beetle larva.

As mean as the green tiger beetle larvae look, they’re not without their enemies, but we’ll take a look at the most devilish of these in the next post.

Maltese madness

Every Spring-time, lots of fat blokes with guns take pot shots at any birds that happen to be flying over Malta en-route to somewhere else. They’re supposed to confine their blood-lust to species like turtle dove and quail; however, when Spring is in the air nothing with feathers is safe in the skies of over Malta.

Countless birds of prey and lots of other protected bird species get blasted out of the sky by men who, deep down, probably have more issues than a box of tissues.

Every year, various groups and individuals try and stop this senseless slaughter, but to no avail as the island’s chief of police is the one with the biggest blunderbuss and the most ammo, squealing with delight at every defenceless bird he riddles with shot.

Malta is part of the EU, but somehow they get away with letting this happen. Please help shame the Maltese government into stopping this madness by signing the petition below:

Petition to ban illegal bird hunting in Malta

Take a look at the site for more information on what happens and how this can be stopped.

An osprey mortally wounded by the galoots with guns Malta.

Speedy water skimming beetles

The Stenus rove beetles are truly blessed in bizarre adaptations. If telescopic mouthparts weren’t enough (see last post), they also have one of the most impressive defences in the animal kingdom. Often, these beetles are found in waterside habitats, where they wander about on the ground and in the vegetation shooting their spiky mouthparts out at anything that looks at them in the wrong way. Their small size and long legs means they can also take to the water and scull along as if they were walking – their weight supported by the water’s meniscus. This in itself is not all that impressive – there are lots of animals that walk on water, including lizards and even mammals (if you believe some of the stories).

If danger threatens while they’re on the water, these beetles emit an oily combination of alkaloids known as stenusin from the pygidial glands at the tip of their abdomen. This substance is so hydrophobic that as it hits the water it spreads with such force that the beetle is propelled forward at terrific speed, well, relatively. The velocity the beetle reaches is equivalent to 600-900 km/h in human terms and it does this in a fraction of a second –acceleration that would turn you or I inside out. Needless to say, any small predator will be completely bamboozled by the sudden disappearance of its dinner.

Unfortunately, there’s no photos of this as it all happens rather quickly.

There’s more about these beetles in the book, Extraordinary Animals

Further reading

Schildknecht, H. et al. (1976b). Defense chemistry of Stenus comma (Coleoptera: Staphylinidae) LXI. J. Chem. Ecol. 2: 1-11.

Ravenous rove beetles

Catching prey is far from easy, that’s why predators have evolved a host of means of catching and subduing their food. Some of the most bizarre of these are in the insect world where evolution has run riot. A bit like chameleons, some insects have dispensed with having to pounce on their prey, instead relying on mouthparts that can be shot out to bring the prey within chomping range of the mandibles.

Stenus rove beetles are just such animals. These tiny insects have a structure called a labium that can shot out by forcing blood into it – much like the unfavourable creatures in the Alien films. In absolute terms, the distance it can shoot this structure out to is nothing to write home about, but for the beetle it’s the difference between securing an appetizing aphid or a succulent springtail and going hungry.

A Stenus rove beetle (Stenus fossulatus) looking for something to shoot its mouthparts at

The SEM images below show what this structure looks like at increasing magnifications (taken from the paper below). You can see in the last photo the business end of the labium is covered with brush-like setae, which probably ensure the prey is well and truly stuck when the beetle retracts its telescopic face.

The telescopic labium of Stenus comma (Thomas Bauer and Martin Pfeiffer) prm = praementum, mt = membranous tube

The fearsome looking business-end of Stenus comma's protusible labium (Thomas Bauer and Martin Pfeiffer) pgl = paraglossa, pm = palpus maxillaris

The setae covered paraglossa of Stenus comma (Thomas Bauer and Martin Pfeiffer)

The brush-like setae on the paraglossa of Stenus comma's labium (Thomas Bauer and Martin Pfeiffer)

Just what they use these elaborate mouthparts to catch is more of a mystery, as it’s not very good for catching springtails – the primitive six-legged animals that share the beetle’s habitat. Springtails are often covered in scales that come off very easily giving predators the slip, even those with abilities worthy of a science fiction film. The beetle’ telescopic mouthparts may come into their own when the insect is crawling around in low growing vegetation – enabling it to grab aphids or other insects on nearby stems and leaves that would otherwise be out of reach. There’s also the possibility the mouthparts are used to probe crevices in to which the beetle can’t quite squeeze.

There’s more about these beetles in the book, Extraordinary Animals

Further reading

Bauer T, Pfeiffer M (1991) Shooting springtails with a sticky rod the flexible hunting behavior of Stenus comma (Coleoptera, Staphylinidae) and the counter-strategies of its prey. Anim. Behav. 41: 819-828

Betz, O. Comparative studies on the predatory behaviour of Stenus spp. (Coleoptera: Staphylinidae): the significance of its specialized labial apparatus. Journal of Zoology 244, (1998) 527-544.

Betz, O. Life forms and hunting behaviour of some Central European Stenus species (Coleoptera, Staphylinidae). Applied Soil Ecology 9, (1998) 69-74.

Betz, O. A behavioural inventory of adult Stenus species (Coleoptera: Staphylinidae). Journal of Natural History 33, (1999) -1712.

Betz, O. and Fuhrmann, S. Life history traits in different life forms of predaceous Stenus beetles (Coleoptera, Staphylinidae), living in waterside environments. Netherlands Journal of Zoology 51, (2001) 371-393

Scoundrels – #1

Evolution has been very creative when it comes to mimicry, but the most incredible in my opinion and therefore at number one in the scoundrel chart, are the freshwater molluscs known as pocketbook mussels (Lampsilis spp.). These unassuming molluscs spend their adult lives embedded in the sediment and gravel of streams and rivers doing very little except filtering edible muck from the water and breeding. However, indolence aside, the mimicry exhibited by these mussels is surely one of the most bizarre examples of this phenomenon in the animal kingdom and one that evolved as a means of enhancing reproduction rather than as a way of catching prey or bamboozling predators.

A pocketbook mussel embedded in a stream-bed not really doing much (USFWS).

In many respects these animals look like any other bivalve mollusc, but what sets them apart is the unusual extension of their fleshy mantle that grows beyond the confines of the protective shell valves to wave around in the water. This fleshy protuberance can look astoundingly like a small fish and this is no coincidence because this fishy appendage is actually a lure to draw fish near so they can be press-ganged into the mussel’s reproductive strategy. The lure is so convincing, with ‘eyes’ and markings, that curiosity gets the better of small fish swimming by. Perhaps the fish see the lure as a potential mate, a shoal member or as an interloper to be chased from their territory. Regardless of the motivation, the fish edges closer and closer to the mussel to investigate the unusual looking ‘fish’. When it’s eye to eye with the lure, the mussel springs its trap and the little fish gets doused with the mollusc’s larvae, nasty-looking miniature versions of the adults, known as glochidia. These larvae are parasitic and they get drawn under the fish’s gill plates where they latch onto the blood-rich tissues of the gills using a long adhesive hair and hooks on their tiny shell valves. Attached to their host, the larvae stimulate the development of a cyst which provides them with protection and nourishment for anywhere between 10 to 30 days.

The fishy lure of the pocketbook mussel - Lampsilis ovata (USFWS).

Another fishy lure - the elaborate mantle protuberance of L. fasciola (Dick Neves).

One final fishy lure, this time of Lampsilis reeveiana (USFWS).

A pocketbook mussel larva (glochidium). The long thread is adhesive and in combination with the teeth on the shell valves is used to help the larva latch on to the fish's gills.

After a couple of weeks spent feeding on the unfortunate fish’s blood and gill tissue, the larvae leave their cysts and sink to the bed of their aquatic home where they begin their sedentary way of life probably a long way from where their mother sprang her trap. In addition to the fishy ruse, other species of freshwater bivalves, closely related to the pocketbook mussels, dupe hungry fish into dispersing their young by releasing their larvae in encapsulated masses known as ovisacs that have more than just a passing resemblance to a juicy worm or insect larva. As ovisac tumbles away from the mother mussel a fish rushes over and takes a bite from it only to expose itself to the glochidia contained within.

An ovisac produced by a female Ouachita kidneyshell mussel with more than a passing resemblance to a insect larva or worm. When a fish bites the sac it ruptures and the glochidia are released (USFWS)

The lifecyle of pocketbook mussels showing how these sedentary bivalves go about dispersing their young.

The use of mimicry in these ploys allows a sedentary mollusc to attract a vehicle for the safe dispersal of its young and in my view it is the most incredible example of an animal pretending to be something else to give it an edge in the struggle for survival. For this reason the pocketbook mussels and their relatives top the scoundrel chart.

There’s more about these marvellous molluscs in the book, Extraordinary Animals

Scoundrels – #2

You’d think that transvestism might be a uniquely human trait, but the animal kingdom is not without other species where males routinely imitate females, well, without the hairy arms and the ill-fitting stilettos.

Interestingly, there are even transvestite insects and the males of one of these species, a rove beetle from Central America, subtly imitate females as a means of getting access to and reproducing with bone-fide females. The transvestite rove beetle (Leistotrophus versicolor) is a denizen of the rain-forests of Costa Rica, where, like lots of other rove beetles, it makes a living by seeking out decaying plant and animal matter to feed on the adult insects and larvae that make use of these ephemeral resources. These honey-pots don’t last long in the super-charged biological activity of the hot and humid tropical forests, so when normal male rove beetles find them they guard them because they also attract females, allowing a male to assemble a harem.

The transvestite rove beetle (Prof. J Alcock)

Males of this rove beetle are divided into two types, normal butch specimens and small, effeminate ones. The small, effeminate males can find honey-pots, but they have little hope of defending them against the bigger males, so their chances of building a harem are next to nothing. These males have evolved another means of making sure they pass their genes onto the next generation. They sneak past the normal males using their effeminate appearance as a disguise and under the harem owner’s nose they have it away with the females he has been so carefully guarding. This strategy is almost flawless, but now and again the transvestite male is caught prancing around in the harem by the owner male and the only way he can avoid being torn limb from limb is by assuring the aggressor of his femininity and giving in to a ‘mating’.  One sore behind later, the transvestite male carries on sneakily copulating with the females in the harem, only slightly more nervous for his unpleasant experience.

A female mimicking male L. versicolor (front) gets checked out by a butch male of the same species (rear) (Prof J. Alcock).

The duplicity of these beetles is not just limited to transvestism, as they can also produce odours that mimic the smell the rotting matter in order to attract prey, namely flies. The rotting matter these beetles depend on can often be hard to come by, so they need an alternative means of finding suitable prey. Within the tip of their abdomen these beetles have a pair of pygidial glands that can be popped out to smear an odorous secretion on a suitable platform, such as a leaf. Flies are drawn to this odour in the hope of finding some filth to feed on to lay their eggs on, so all the beetle has to do is to wait until a suitable victim scuttles within pouncing distance.

A tranvestite rove beetle has smeared some of the malodorous secretion from its pygidial glands on a leaf and now it waits for a fly to be drawn to the trap (Prof. J. Alcock).

The ability of this rove beetle to use mimicry in reproduction and feeding makes it one of the most impressive con-merchants in the animal kingdom and for this reason it is at number two in the scoundrel chart.

There’s more about this beetle in the book, Extraordinary Animals

Further reading

Alcock, J. and Forsyth, A. Post-copulatory aggression toward their mates by males of the rove beetle Leistotrophus versicolor (Coleoptera: Staphylinidae). Behavioral Ecology and Sociobiology 22, (1988) 303-308.

Forsyth, A. and Alcock, J. Female mimicry and resource defense polygyny by males of a tropical rove beetle, Leistotrophus versicolor (Coleoptera: Staphylinidae). Behavioral Ecology and Sociobiology 26, (1990) 325-330.

Forsyth, A. and Alcock, J. Prey luring as alternative foraging tactics of the fly catching rove beetle Leistotrophus versicolor (Coleoptera: Staphylinidae). Journal of Insect Behavior 3, (1990) 703-718.

Scoundrels – #3

Orb-web spiders build an intricate trap to catch their prey, normally hapless insects; however, there are some spiders in this family, notably the bolas spiders that have almost entirely dispensed with a web. Instead they rely on just a short thread with a blob of sticky silk on the end. This is not merely a half-baked attempt at making a web; the prey capturing apparatus of a spider who simply can’t be bothered to spin a proper web. No, far from it, Bolas spiders know that it’s not what you’ve got it’s how you use it that counts.

The sorry looking ‘web’ is part of a delicious ruse involving the lasso skills of a gaucho and the malodorous abilities of the paussine beetles (see Scoundrels #6). When night falls, the bolas spider (Mastophora spp.) constructs itself a small silken gantry to hang from in order to prepare its trap. It makes its bolas and waits, listening for the faint sound of moth wings on the night air. Should a moth flutter within range, the spider whirls its bolas in the hope of connecting with the moth; however, if it were to rely on chance alone, its bolas at the ready, the spider might be waiting a long time for a moth to flutter within range of its trap, so to tilt the table of fortune in its favour the spider is capable of emitting an odour that has more than a passing resemblance to the pheromones given off by cutworm moths (Nephelodes spp., Lacinipolia spp.)

The male moths get a whiff of this heady odour and make straight for it. As the moth draws closer to the source of the scent, its tiny brain is probably filled with happy thoughts about how all that time spent as a caterpillar is not going to go to waste. He has found a female, he’ll get it on with her and his work will be done. Just as his feeling pretty chuffed with himself the deceptive spider’s whirling bolas connects squarely with his solid thorax. The blob of silk on the end of the bolas sticks tight and the spider draws him in. For this moth, the struggle for survival is over, which is a shame because he was doing so well – he’d survived the horrors of hatching , the lottery of larvalhood and the perils of pupation, just to get caught by a spider that couldn’t even be bothered to build a proper web. Where’s the justice?

This bolas spider is waiting for its mothy odours to attract some prey (Prof. KV Yeargan).

The spider goes about digesting the moth from the inside out and when she’s finished she sets her trap again, because there are other moths on the wing and one species, the smoky tetanolita (Tetanolita spp.) is also drawn to the fake promises of mates issuing from the bolas spider’s glands.

Even juvenile bolas spiders are masters of deception. They hang about on the edges of leaves emitting an odour that smells like female flies. Sooner or later, a desperate male fly, his tiny brain addled by thoughts of reproduction, casually scuttles up to the wingless, eight-legged ‘fly’ and tries it on, only to be quickly despatched.

Not only are bolas spiders adept at aggressive mimicry, but they also use defensive mimicry to prevent them from falling prey to their own enemies. Like many invertebrates, they mimic bird-droppings, and for good reason, as there are few animals known to relish this particular type of waste. They sit about on leaves, pretending to be a bit of bird cack and lo and behold, nothing tries to eat them.

A bolas spider pretending to be a bird dropping (W. Mike Howell).

For the ingenious deception displayed by the bolas spiders they are worthy of the bronze medal in the scoundrel championships.

Big, beastly and very extinct birds

In the right circumstances birds can evolve into giants. In the vast majority of cases they have done this on oceanic islands in the absence of any large land predators and most of these extinct giant birds are decidedly lacking when it comes to predatory ferocity, as birds like the moa and elephant bird attest; big, but decidedly vegetarian animals. However, a long-legged bird living in South America several million years ago, probably very similar to the living seriemas (Cariama cristata and Chunga burmeisteri), gave rise to a group of birds collectively known as terror birds (, technically known as phorusrhacids) and as their name suggests they were not the sort of feathered critters you would find nibbling nuts at a bird-table. They were big birds; the smallest of the 17 known species were at least 1m tall, while Brontornis burmeisteri stood as high as 3m and may have weighed as much as 350–400 kg, but even B. burmeisteri may have looked a bit pathetic next to an even bigger species, the skull of which was discovered by a high school student in Patagonia in 2003. There’s every possibility these animals were the largest birds ever to have lived and all of them were undoubtedly fierce predators. Why these nightmarish birds came to evolve in South America is not fully understood, as no other place on Earth has ever produced a group of predatory giant birds. Gigantism in birds is normally associated with herbivory, yet whatever conditions prevailed in South America many millions of years ago allowed the evolution of a varied group of feathered carnivores that were around for a huge stretch of time; from around 60 million years ago to about 1.8 million years ago, which goes to show how successful these birds were.

A selection of terror birds. A - Brontornis burmeisteri; B - Paraphysornis brasiliensis; C - Phorusrhacos longissimus; D - Andalgalornis steuletti; E - Psilopterus bachmanni; F - Psilopterus lemoinei; G - Procariama simplex; H - Mesembriornis milneedwardsi and the silhouette of a man (1.75 m high) for scale (Herculano M.F. Alvarenga)

Following the extinction of the dinosaurs, many niches in the Earth’s ecosystems were left wide open for the vertebrate survivors – the mammals, birds, and remaining reptiles to evolve into, and for a while, apparently, the terror birds had a power struggle with the mammals for the dominance of the terrestrial ecosystems in South America. Many of them were big and powerful enough to have been the top predators at the time, and many mammals were definitely their prey.

All but one of the terror birds paleontologists know of today have been unearthed in South America. One species (Titanis walleri) managed to reach North America, and it appears to have been quite a success, surviving for more than three million years until it disappeared around 1.8 million years ago – the last of its kind to become extinct. Even though this American species was not the biggest terror bird it must have still been a terrifying animal. Its vital statistics are impressive: 1.4 – 2.5m tall and 150kg in weight. It also had an immense, hooked bill and with such an impressive beak it could have probably swallowed a lamb-sized animal in one gulp.

Although we can piece together the skeletons of the terror birds it’s impossible to know what their plumage was like. However, we can look at living birds for clues, and if the other flightless birds are anything to go by, the terror bird’s feathers may have been rather hair-like. Like the vast majority of flightless birds, terror birds had stubby little wings, but what they lacked in the wing department they more than made up for with their long, powerful legs that ended in large feet and long claws. These legs gave these animals a good turn of speed and it has been estimated that some species of terror bird could reach speeds of 100kmh – comparable to a cheetah. The combination of running, big talons and a monstrous beak made the terror birds very effective predators. It is possible to imagine one of these birds snapping at the hooves of ancient mammals as it pursued them across the grasslands of the Americas. Smaller animals were probably immobilized with the sharp talons before being torn apart by the fearsome hooked bill or even swallowed whole after having their skull crushed in the bird’s vice-like grip. Larger prey animals may have been disemboweled with Kung-Fu styles kicks and it is even possible that crushing kicks may have been used to crack the larger bones of big prey to get at the nutritious marrow within.

Skull of a terror bird (Titanis walleri). This is about 50cm long (Ross Piper)

Even if the last terror bird became extinct around 1.8 million years ago, these were successful animals that, as a group, survived for more than 50 million years, some of them even taking on the mantle of top land predator in the ecosystems in which they lived. However, around 2.5 million years ago (during the Pliocene epoch) something happened that completely changed the course of life for South America’s unique animals – the Great American Interchange. The land bridge that eventually appeared between North and South America, what is now known as the Isthmus of Panama, allowed animals from the north to migrate into South America. Among them were lots of predatory cats and it has been proposed these animals were so effective as predators that they outcompeted the terror birds. The talons and beaks of the terror birds were no match for the teeth, claws, and hunting prowess of the invaders from the north. This is a very neat answer for the cause of the extinction of the terror birds, but, the extinction of successful animals is very rarely due to one factor, but a combination of events. Perhaps climate change directly affected the terror birds by changing their habitats and the populations of their prey. Although there is a great deal we don’t know about the life and times of the terror birds we do know that one of their number somehow managed to cross into North America and spread through the southern states. For a long time it was assumed that the American terror bird spread north via the land bridge, but analysis of its ancient bones paints an alternative picture as they appear to have reached the southern states of America before the land bridge formed. Perhaps falling sea levels, due to the growth of the polar ice sheets, revealed a path of ‘stepping stones’ across islands in the gap of open ocean in what would become the Isthmus of Panama, allowing the giant birds to colonize the prehistoric North America. Maybe other species of terror bird, the remains of which are as yet undiscovered, also reached North America before following the rest of their amazing kind into the pages of earth history.

Terror bird (Paraphysornis brasiliensis) reconstruction (Renata Cunha from Extinct Animals, Greenwood Press)

Read more about the terror birds and other beasts that have long since ceased being extant in the book Extinct Animals

Further reading: Marshall, L.G. The terror birds of South America. Scientific American 270 (1994) 90–5; Alvarenga, H.M.F. and Höfling, E. a systematic revision of the phorusrhacidae (aves: ralliformes). Papéis Avulsos De Zoologia 43 (2003) 55–91; MacFadden, B.J., Labs-Hochstein, J., Hulbert, R.C., and Baskin, J.A. Revised age of the late Neogene terror bird (Titanis) in North America during the Great American Interchange. Geology 35 (2007) 123–126.

Scoundrel – #4

The paussine beetles (see scoundrels – #6) are very good at mimicking the odour of ants in order to run amok in the nests of their hosts, gorging themselves on eggs, larvae and pupae. This is the sort of behaviour we’ve come to expect from ground beetles, the dark, scuttling creatures that they are. If someone suggested that a butterfly was capable of the same unpleasant behaviour, your initial course of action might be to take the cad by the lapels and rough him up a bit so that he repents for blackening the good name of such charming insects. Unfortunately, they would be right, so you’d have some apologising to do.

Anyway, butterflies are capable of behaving in some very despicable ways, especially the larvae. The adults are fleeting, shallow, lustful creatures, only interested in getting it on with the opposite sex, but the larvae have the difficult task of eating as much as possible in the shortest amount of time and to do this some species have found they can get the job done very successfully if they pull the wool over the beady eyes of ants.

The alcon blue butterfly (Maculinea alcon) is one such interloper and the story begins around the end of July in the European summer when the female alcon blues deposit their white eggs on the flowers of marsh gentian. A few days later the tiny caterpillars hatch out of the bottom of their egg and munch a tunnel straight into the closed flower of the gentian and here it remains for around two weeks, safe from its predators, eating some of the flower tissue and developing seeds, but not growing very much. In the flower, the caterpillar sheds its skin three times and after the final time it’s ready to take its leave of this safe house, so in the early morning or evening it chews its way from the base of the flower and shuffles along the petals to the apex of the bloom. Apparently tired of its nursery it releases its grip and falls to the ground on a silken thread and waits.

And so the ruse begins - a female alcon blue butterfly laying eggs on a marsh gentian flower (David Nash).

This is the riskiest time of its short life. Predators abound amongst the short turf and all of them would make short work of a tiny, plump caterpillar; however a small, foraging red ant (Myrmica spp.)gets a whiff of the caterpillar and goes for a closer look. The ant, seemingly intrigued and mesmerized by the caterpillar, strokes it all over with its quivering antennae. If it could, the caterpillar would be breathing a huge sigh of relief as this is exactly what it was waiting for. This is a result. To express its relief the ant produces a drop of sweet fluid from its rear end, which the ant immediately starts suckling. This can go on for some time, until the caterpillar flattens the middle or rear of its body, a simple act that is apparently enough to completely fool the ant that the caterpillar is a grub from its own nest that has somehow gone walkabout. It tenderly picks the caterpillar up in its jaws and makes for the nest.

Get in! This is just what the caterpillar was hoping for (David Nash).

The caterpillar is deposited in the nursery of the ant’s nest alongside the countless young of the colony. Here, it blends right in. It smells right and smell to ants is all important. The ants feed the caterpillar by regurgitating nutritious fluid and somehow these tiny tricksters persuade the ants to give them preferential treatment so that they receive more attention and food than the ant grubs. To add insult to injury, the caterpillars also supplement their liquid diet by scoffing the odd ant grub or two. On such a nutritious diet the caterpillar grows quickly, increasing its weight by amount 100 times during its first month in the nest. The caterpillar stays put in the nest for some time, living it up in the safety of the nest at the expense of the trusting ants and only when the following summer arrives does it begin the transformation that will turn it into a fine butterfly.

The alcon blue caterpillar lives it up in the nest with the ants at its beck and call (Darlyne A. Murawski).

When it emerges from its chrysalis as an adult butterfly deep underground the tricks used to deceive the ants have long since worn away. It no longer smells like an ant and it certainly doesn’t look like an ant larva, albeit a massive one. At this point, the ants are probably beginning to twig: “Wait a minute… is that the fat sister we’ve been feeding for ages…isn’t she a looker?…must have got her dad’s genes.” “Saying that though she does look a lot like those weird fluttery things we see on the outside……..but what’s it doing in here?” As the penny drops it’s time for the butterfly to leg it. The ants see the butterfly they have nurtured for the best part of a year as nothing more than an intruder and if they get hold of the low-down mimic they’ll do unspeakable things to it. Fortunately, the butterfly has one last trick to avoid being held to account and as the angry ants try and bite the fleeing charlatan all they come away with is a mouthful of scales. The whole body of the newly emerged butterfly is densely covered in loose scales and the ants cannot get a grip on it, so by the scales on its behind it manages to give its trusting guardians the slip and leaves the nest by the nearest exit without so much as a bye or leave. Above ground it makes for a perch among the lofty vegetation of the meadow where its wings will inflate and harden in the summer sun until it is ready to flutter off like butter wouldn’t melt on its proboscis.

Who'd have thought a butterfly would be capable of such things (Pieter C. Brouwer).

For the sheer audacity of these butterflies they’re at number four in the scoundrel chart.