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The magnificent timber rattlesnake (Crotalus horridus) is a venomous pit viper which lives throughout the populated northeastern portion of the United States of America from Texas to New England. Ferrebeekeeper has considerable affection for the dangerous reptile (at an appropriate distance, of course!) and has already referenced the timber rattler as a metaphor for national liberty and, strangely, as a point of comparison for a large sports venue. But timber rattlesnakes are so much more. They were one of the first new world animals to utterly fascinate and horrify European colonizers. In the colonial period a serious rattlesnake bite was a death sentence (although we now have anti-venom) but the original natural scientists did not appreciate how complicated and remarkable the snakes were in other aspects.
As I write this, it is November and the rattlesnakes are all abed for the winter. Because they live in areas with harsh winters, timber rattlesnakes spend more than 7 months a year in hibernation. Large numbers will nest together in a community den—sometimes together with other snakes such as blacksnakes and copperheads. The den is usually a rocky chasm which extends deep beneath the frost line, and rattlesnakes may travel many miles to reach their hibernation den (a bi-annual journey which puts the snakes at great risk from predators and from cars).
Because of their large and diverse territory, timber rattlesnakes come in different sizes, colorations, and even have different venom types. The average timber rattlesnake grows to 100 cm (39 in) long and weighs between a half kilo and a kilogram (1 to 2 pounds). Much larger specimens are known (although there is considerable ridiculous dispute about the upper ranges of rattlesnake size). Female timer rattlesnakes are viviparous although, unlike mammals, rattelsankes protect their eggs within their bodies until they hatch. Rattlesnakes give birth to litters of 6-10 fully formed, fully poisonous little baby snakes, but they can only reproduce every few years since the experience is very hard on them.
Like catfishes, timber rattlesnakes have senses which we do not possess. Pit vipers are so named because they have nostril like spots (pits!) on the side of the head which they use to perceive infrared electromagnetic radiation. These pits are quite sensitive and act as third eyes. Snakes (and many other animals) also have special auxiliary olfactory sense organs called Jacobson’s organs which are extremely sensitive to various smells/tastes. Snakes characteristically pick up chemical traces with their tongues and waft these smells before their Jacobson’s organs in the characteristic tongue-flicking which is such a trademark.
Of course rattlesnakes are not just sensitive—they are also expressive. Among all other snakes they are distinctive in that they have a specialized structure at the end of their tail for making a warning noise. Rattlesnake rattles consists of hollow button-like segments which produce a distinctive buzzing when the snakes vibrate their tails. As a rattlesnake sheds her skin (every few months), she adds a new button to her tail. Rattles however are not perfect records of how many times snakes have shed their skin—sometimes buttons get knocked off, or just become brittle and fall away. The rattle has a high frequency and varies in loudness between 60-80 decibels from a distance of one meter (which falls somewhere between the noise level of an animated conversation and a garbage disposal). Ironically, the rattlesnakes themselves are deaf.
The venom of timber rattlesnakes varies in toxicity depending on the subspecies, but the most toxic rattlesnakes are extremely venomous. Type A venom is a neurotoxin whereas type B venom is hemorrhagic and proteolytic (which is to say it causes bleeding and breaks down fundamental body proteins). Type C venom is largely harmless. In Arkansas and Louisiana, timeber rattlesnakes are particularly dangerous because cross-breeding has resulted in snakes which have type AB venom (yikes!). To a lesser extent rattlesnake venom also contains esoteric myotoxins which rapidly kill muscle tissues. This deadly cocktail of different venoms is of great interest to pharmacologists who continue to study the various toxic proteins to tease out potential medicines.
Fortunately timber rattlesnakes are good-natured and do not generally bite without much posturing, rattling, hissing, and feinting. They keep their retractable fangs folded up in a mouth sheath when not in use and they are capable of varying the amount of venom they inject based on how they are feeling. It is best not to antagonize rattlesnakes lest they abandon their amiable disposition.
Timber rattlesnakes are gifted ambush predators which particularly prey on small mammals such as squirrels, chipmunks, mice, and other rodents, but they also eat amphibians and birds. In turn rattlesnakes are preyed on by owls, hawks, bobcats, foxes, crows, skunks, and even turkeys! Rattlesnakes are an important part of the woodland ecosystem, but they face serious threats from habitat loss and traffic (cars being indifferent to the protective poison of snakes).
Not only are many rattlesnakes killed by traffic, they must also face persecution. Many are killed by angry villagers carrying torches and pitchforks. Gawping Texans take this to a particular extreme and organize great “rattlesnake round-ups” where huge numbers of rattlesnakes are wantonly tormented and killed for no particular reason (except perhaps to demonstrate a hatred of the world and its creatures). This is particularly sad since rattlesnakes, like whales, or elephants (or ourselves) are k-selected animals. They live long but reproduce slowly, which makes them especially vulnerable to population crashes.
If, by some appalling circumstance, you have read this far while a timber rattlesnake sits nearby buzzing its tail, you should run away from the snake! Do not attempt to molest it. If you feel threatened, call animal control. The timber rattlesnake is already vanishing from great expanses of its territory. It would be a shame if this beautiful and fearsome serpent were to slip away from the earth.
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”.
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.
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.
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.
The genus Lynx consists of four furtive species of medium-sized wildcats which inhabit giant swaths of the northern hemisphere. The cats are solitary hunters which prey on a wide range of animals including lagomorphs (rabbits and pikas), rodents, foxes, sheep, goats, various species of deer and chamois, as well as gamebirds such as grouses, turkeys, ptarmigans, and waterfowl. This list is hardly comprehensive–all four species of lynx are opportunistic predators which will catch and eat all sorts of insects, reptiles, fish, and amphibians.
Lynxes share common features such as bobbed tails, large paws, tufted ears, buff spotted coats, ruffs under the neck, and long whiskers. All four species also utilize a common reproductive strategy. Lynxes and bobcats mate in winter and the female then raises her litter of two to four kittens over the course of a second winter. After one winter with their mother, the young adults move out on their own. Lynxes like to sleep in sheltered dens provided by caves, deadfalls, or hollow logs. They are strongly territorial (although males maintain larger territories which overlap each other and may contain the territories of many females).
Although the classification of the family Felidae is continuously being revised, the current members of the Lynx genus are as follow:
The Eurasian lynx (Lynx lynx) is the largest lynx, which ranges from Europe, across all of Siberia to China. Male Eurasian Lynxes weigh from18 to 30 kg (40 to 66 lb) and can stand up to 70 cm (28 in) at the shoulder. Like all lynxes, the Eurasian lynx is a stalking predator which silently shadows its prey before pouncing for the kill.
The Canadian lynx (Lynx canadensis) a specialist of the arctic forests of Canada which preys largely on snowfoot hares. The Canadian lynx has huge paws which spread its weight out over the snow in the manner of snowshoes. In winter the Canadian lynx grows a thick multilayered coat.
The bobcat (Lynx rufus) is an adaptable predator which ranges from the Atlantic to the Pacific, from Southern Canada deep into Mexico’s deserts. An adaptable generalist, the bobcat can live in any type of forest, as well as in deserts, swamps, and mountains. The successful creatures even live in agricultural or developed lands.
In contrast to the bobcat, the Iberian lynx (Lynx pardinus) is the world’s most endangered cat species. At present there may be fewer than a hundred left in the wild. Once overhunted, the Iberian lynx now suffers from habitat loss (thanks to overdevelopment) and attendant traffic fatalities. In Spain and Portugal rabbit populations (the Iberian lynx’s preferred prey) have crashed because of myxomatosis, a viral disease from the Americas which was introduced to Europe by a short-sighted French bacteriologist. Finally, the once diverse forests of Iberia were replaced with agricultural monoculture which exacerbated the ecosystem destruction.
If the Iberian lynx does indeed go extinct, it will be the first cat to do so since Smilodon. Fortunately the other 3 lynxes are all relatively secure in numbers (although habitat destruction sometimes drives them out of specific areas–particularly in Western Europe).
Superb stealthiness, nocturnal habits, and highly effective camouflage render the lynxes nearly invisible to humans (although people do sometimes hear their unearthly haunting yowls at night). Because of this elusiveness (combined with their keen eyesight and hearing) lynxes have acquired a somewhat otherworldly reputation in folklore and myth. In ancient legends and stories, bobcats and lynxes were said to hold secret wisdom hidden from the comprehension of men or other creatures. They were animals of augury and foresight which occasionally appeared to sorcerers, oracles, and shamans with occult knowledge. According to “Animal Speak” by Ted Andrews, “The Greeks believed the lynx could see through solid objects. In fact it is named for Lynceus, a mythological character who could also do this.” During the middle ages and the Renaissance, the lynx’s ability to see without being seen was linked with the omniscient vision of Christ.
The long association of lynxes with sharp-sightedness lingered into the early modern world where the lynx’s piercing vision became a metaphor for scholarly insight and scientific breakthrough. The world’s first Academy of Science (well, the first one which wasn’t disbanded by the Inquisition) took its name from the lynx: The Accademia dei Lincei, (“Academy of the Lynx-Eyed”, or Lincean Academy), was an Italian science academy founded in 1603 by Federico Cesi, an aristocrat from Umbria. Cesi was passionate about natural science (particularly botany) and he gathered a group of polymaths and geniuses together to observe the natural world and explain it by means of experiments and the inductive method. The society was one of the first to use lenses for scientific purposes and they produced an important collection of micrographs—drawings created with the newly invented microscope. Their most famous member, Galileo Galilei was famous the discoveries he made with a telescope—discoveries which altered the way humankind perceived the universe. Even as the Church turned the zealous eye of the Inquisition upon Galileo, the society supported him and made sure his books were published and his ideas were disseminated (thanks largely to Cesi’s aristocratic connections and fortune). In fact, after joining the society, Galileo always signed his name as Galileo Galilei Linceo.