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Antennarius commerson – Giant frogfish (Commerson’s frogfish)
This is Commerson’s frogfish aka the giant frogfish (Antennarius commerson). It is a voracious carnivore which attacks anything small enough to be prey (which is pretty much anything smaller than itself–since the fish has an extremely extensible body). Commerson’s frogfish is a chameleon—it can change color to resemble the tropical sponges of its native habitat –yellow, red, orange, gray, or black, with all sorts of stripes and splotches (though the creature seems to betray a predilection for yellow).
Giant frogfish, (Antennarius commerson) photo by Rokus Groeneveld
Giant frogfish, Antennarius commerson
(photo by “Hole in the wall”)
The frogfish is an anglerfish and its front dorsal spine is tipped with a pinkish shrimplike lure (a feature known to biology as an esca). The fish lives in tropical and semi-tropical water of the Indo-Pacific (an eco-region which comes up repeatedly in this blog). Despite being known in English as the giant frogfish, Antennarius commerson only grown to 38 cm (15 inches) in maximum length which demonstrates that horror is relative (and that frogfish are not large from a human perspective). Although it is not classically beautiful by any stretch of the imagination, there is something oddly charming about its grumpy expression. I hope you enjoy looking at it as much as I do!
Antennarius commerson – Giant frogfish (Commerson’s frogfish)
Copyright Teresa Zubi
The Life Cycle of Phengaris rebeli (image via http://sciencythoughts.blogspot.com)
It’s October—the month of costumes, masks…and monsters. To start out this year’s Halloween season on an appropriately ghastly note, today’s post deals with a horrifying creature which relies upon disguise to feed itself: namely, the Mountain Alcon Blue butterfly (Phengaris rebeli).
Native to temperate grasslands of Central Europe, the Mountain Alcon Blue has silvery blue which are stippled in little black spots with delicate white edges. The butterfly flits harmlessly about in gentle meadows, finds a mate, and then the female lays her eggs on a pretty gentian flower.
Aww, it’s on a pretty flower (Photo by Tristan Lafranchis)
So why is this delicate alpine beauty a creature of nightmares? When the Mountain Alcon blue larva hatches, it eats the gentian until it reaches a certain size whereupon it falls to the ground and releases an allomone—a deceptive chemical which makes it seem identical to an ant larva. Foraging ants discover the caterpillar and tenderly carry it deep within the protection of the ant hive to the nursery room where the ant larvae are fed and cared for. Then the caterpillar reveals another dark talent: it produces a sound which perfectly mimics the ant queen. Subject to this all-powerful voice of authority, the ants care for the caterpillar as though it were the queen–even going so far as to attack the actual queen. Obeying the dictates of the awful song, the ants feed the still living ant larvae to the caterpillar which devours the helpless young ants like so many little wiggling burritos (well, if juvenile butterflies ate burritos).
Caterpillar with slave ant (photo by Darlyne A. Murawski)
When the butterfly pupates into an adult, it loses its ability to mimic ant chemicals or produce the queen’s voice. The ants recognize it as an invader and attack, but the butterfly’s scales are designed to resist their mandibles. It flees the crippled and abused ant colony and begins the cycle over again.
Isn’t nature beautiful? (photo by Guy Padfield)
Yet monsters still must fear other monsters and there is an even more invidious predator which seeks out the Alcon larvae deep within ant hives. This is the parasitic wasp, Ichneumon eumerus, which infiltrates ant colonies which are being preyed on by Phengaris rebeli larvae. The wasp locates the caterpillar and then releases an allomone which causes the ants to go insane and attack one another. Then in the chaos that follows, the wasp injects its eggs into the living caterpillar. When the eggs hatch they eat the interloper from inside and then burst out of its carcass.
The parasitic wasp Ichneumon eumerus preying on Phengaris caterpillar while an ant stands by waiting for doom. (Image: J.Thomas/Natural Visions)
Maculinea arion
Hey, look at that! It’s a delicate pale blue butterfly (Maculinea arion) from Europe and northern Asia. What could this ethereal creature have to do with the horror theme which this blog has been following as a lead-up to Halloween? In fact, what does the butterfly have to do with any of Ferrebeekeeper’s regular themes? Butterflies are lepidopterans rather than the hymenoptera we favor here.
As it turns out—the butterfly has a lot to do with hymenopterans. Maculinea arion, or “the large blue butterfly ” to use its not-very-creative English name, may look innocent as a butterfly, but in its larval stage the creature is both appalling and remarkable. Alcon caterpillars are myrmecophiles—which means the caterpillars live in association with ants. Despite the Greek meaning of ”myrmecophile” (to love ants) the relationship is anything but loving on the part of the Alcon caterpillar–unless love is meant in the same way as “to love ham”.
Maculinea arion (Large Blue) larva carried by ant (Drawing by Frohawk)
M. arion caterpillars are relentless predators of ant larvae. The way they obtain this fragile foodstuff is remarkable for sophistication and ruthless guile. When a caterpillar hatches, it lives for a few days on wild thyme or marjoram plants. The caterpillar then secretes a sweet substance which attracts red ants which carry the larva back to their tunnels.
Inside the ant hive, the caterpillar produces pheromones and chemical scents which mimic those of the ant queen. It also scrapes a small ridge on its first segment to produce the same noise as the ant queen. The ants are deceived by the caterpillar’s mimicry and they take it to the chamber where they rear their own larvae. The ants wait on the caterpillar as though it were the hive monarch and they even feed it ant larvae—their own undeveloped siblings. Once it pupates, the butterfly scrapes the inside of its chrysalis to continue the deception. When the butterfly emerges from its cocoon the hapless ants carry it outside and guard it as its wings harden—whereupon the butterfly departs to mate and lay eggs on wild thyme or marjoram plants.
Phengaris alcon
The Maculinea Arion is not the only caterpillar to make use of this strategy. The Phengaris alcon butterfly acts in almost exactly the same way. Here is where the story becomes impressively crazy. A parasitoid wasp, Ichneumon eumerus, feeds on the alcon caterpillar inside the ant hive. The wasp infiltrates the hive by spraying a pheromone which causes the ants to attack each other. While they are busy fighting, the wasp lays its eggs inside the caterpillar. The wasp larvae hatch into the body of the caterpillar (which the ants think of as a queen) and they eat the caterpillar host safe in the cloak of this deception.
The parasitic wasp Ichneumon eumerus. (Image: J.Thomas/Natural Visions)
If an ant hive becomes too saturated with caterpillars it will die and all three species inside the hive will likewise perish). The red ants in this scenario are constantly evolving new pheromone signals to outcompete the caterpillars and wasps—which in turn coevolve with the ants. It’s strange to imagine the troubling world of deception, chemical warfare, and carnage just beneath the ground.
A Young Cheetah Threatens a Hat
Things have been a pretty grim here at Ferrebeekeeper lately, what with the inexorable takeover of the labor market by machines, the child-killing Christmas demon Krampus, and the death of the universe. To cheer things up as we go into the weekend, here is a post about baby cheetahs. Some people may claim this topic is a cynical attempt to exploit the endearing cubs and drive up ratings. To those naysayers I respond “baby cheetahs!”
Cheetah Cubs must survive by hiding (image from http://cutearoo.com)
Cheetahs (Acinonyx jubatus)are well known as the fastest land animal–capable of running at blazing speeds of up to 120 km/h (75 mph). To run at such a velocity the cheetah was forced to forgo some offensive advantages possessed by other comparably-sized cats. Cheetahs’ jaws are smaller and their claws are permanently fixed in place–which makes their slashing implements shorter and duller than the razor sharp claws of other hunting cats. Because they concentrate on running prowess to hunt they can never risk a sports injury from fighting. These adaptations make it difficult for mother cheetahs to defend their cubs from predators. Naturally the tiny cubs can not rely on the mother cheetah’s best defense—her legendary speed.
A Mother Cheetah with her cubs at Masai Mara National Reserve in Kenya
Female cheetahs gestate for ninety to ninety-eight days and give birth to a litter of 3 to 9 cubs which each weigh 150 to 300 g (5.3 to 11 oz.) at birth. Since they are so small and slow, (and since they impede their mother’s hunting) cubs suffer from high mortality. Evolution however has utilized certain tricks to minimize the danger they face. Unlike many feline cubs, cheetahs are born already covered with spots. They are adept from a young age at hiding within thorny scrub. Additionally the cubs have a remarkable adaptation to aid their defense. Until they are near maturity, they possess long punk-rock mantle of downy hair along their neck. These wild manes act like ghillie suits—breaking up the cubs’ outlines when they are hidden in dense scrub. The mantles also mimic the Don King style hair of the honey badger (well-known as one of the craziest, bravest, angriest small animals of the savannah). No animals want to mess with honey badgers since the angry badgers despise their own lives only slightly less than those of other living things and are thus extremely unpredictable.
Cheetah Cub
Honey Badger
When cheetahs reach adolescence they lose their mantles and acquire their extraordinary speed, but they still have a certain kittenish playfulness. I was once in the Washington DC zoo on Sunday morning (when the cheetahs are each given a frozen rabbit as a treat). The cheetah run in the National Zoo is long and narrow giving the animals space to build up full speed. The male adolescent cheetahs were excited for their rabbits. They were crouching and slinking back and forth faster than most people could run. One of the adolescent cheetahs got too close to the powerful electric fence surrounding the enclosure and there was a sizzling “pop” as he accidentally touched his delicate nose to the wire. The young male ran off and, because cheetahs are bred to the bone for the chase, his brother ran after him. They ran faster and faster, becoming an exquisite blur. The elegant forms left footprints of fire behind them until the first cheetah slid to a (10 meter) sliding stop and emitted an otherworldly angry chirp-yowl. The spectacle only lasted a moment, but compared to those cheetahs, all other runners I have seen–athletes, racehorses, greyhounds, rabbits–all seemed slow and awkward.
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